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Sample records for open ocean waters

  1. Distant water sailors: parasitic Copepoda of the open ocean

    NASA Astrophysics Data System (ADS)

    Jones, J. B.

    1998-06-01

    Copepods represent one of the largest groups of ectoparasites of marine fish. They have been extensively studied in coastal waters where they have become major pests in aquaculture. However, there is very little information on the ecology of parasitic copepods of fishes in the open ocean. It is now recognised that oceanographic conditions determine the distribution and abundance of oceanic fish. The same conditions also influence the survival of both the individual parasitic copepod and its species.

  2. Mercury in surface waters of the open ocean

    SciTech Connect

    Gill, G.A.; Fitzgerald, W.F. )

    1987-09-01

    Hg was determined in samples of surface seawater and rainfall from coastal and open ocean areas of the northwest Atlantic and Pacific Oceans. Hg concentrations in surface seawater and open ocean rainfall ranged from 0.5 to 11 pM and 6 to 130 pM, respectively. The fluvial flux of Hg to the open ocean was estimated at 1.7 Gg/yr, using mean concentrations of Hg in rainfall and annual rainfall volume estimates for the major ocean basins. Fluvial input, while difficult to reliably assess, was a less important source of Hg to the ocean. The mean residence time of Hg in the surface mixed layer was calculated at 4-7 years. Surface seawater Hg distributions are markedly influenced by atmospheric sources. Due to an elevated supply of Hg to the northwest Atlantic by rain, higher Hg values were observed in surface seawater in the northwest Atlantic Ocean than at low latitudes in the central North Pacific Ocean. Surface seawater Hg concentrations between coastal New England and the Sargasso Sea do not show the large offshore concentration gradient typical of elements which have relatively large fluvial or coastal sources. Rather, the Hg distribution in this region was similar to that obtained for the atmospherically derived constituents Pb and Pb{sup 210}. Surface seawater Hg measurements in the central Pacific Ocean along 160 degrees W between 20 degrees N and 20 degrees S showed a depression in the equatorial upwelling area. In contrast to the surface distribution in the northwest Atlantic, a pronounced on-shore gradient in seas surface Hg concentration was observed in the Tasman Sea. 51 refs., 6 figs., 7 tabs.

  3. Bacterial photosynthesis in surface waters of the open ocean.

    PubMed

    Kolber, Z S; Van Dover, C L; Niederman, R A; Falkowski, P G

    2000-09-14

    The oxidation of the global ocean by cyanobacterial oxygenic photosynthesis, about 2,100 Myr ago, is presumed to have limited anoxygenic bacterial photosynthesis to oceanic regions that are both anoxic and illuminated. The discovery of oxygen-requiring photosynthetic bacteria about 20 years ago changed this notion, indicating that anoxygenic bacterial photosynthesis could persist under oxidizing conditions. However, the distribution of aerobic photosynthetic bacteria in the world oceans, their photosynthetic competence and their relationship to oxygenic photoautotrophs on global scales are unknown. Here we report the first biophysical evidence demonstrating that aerobic bacterial photosynthesis is widespread in tropical surface waters of the eastern Pacific Ocean and in temperate coastal waters of the northwestern Atlantic. Our results indicate that these organisms account for 2-5% of the photosynthetic electron transport in the upper ocean.

  4. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2014-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Sea Spray and Icing in the Emerging Open Water of the...sea spray over the open ocean and the severity of sea spray icing on fixed offshore structures. We will use information on the relationship of the...climatology in ice -free northern oceans from reanalysis data and the time-varying extent of the sea ice cover. Our field campaigns in the second and

  5. Atmospheric water vapor and geoid measurements in the open ocean with GPS

    NASA Astrophysics Data System (ADS)

    Rocken, Christian; Johnson, James; Van Hove, Teresa; Iwabuchi, Tetsuya

    2005-06-01

    We have conducted two experiments to determine precipitable water vapor (PWV) and sea surface heights from a cruising ship in the open ocean. During the first experiment (July 7-13, 02) GPS and radiosonde PWV agreed at the 2 mm rms level. During the second experiment (Aug 23-30, 03) GPS compared at 1.5 mm rms (1.1 mm GPS high bias) with eight ship-launched radiosondes and at 2.8 mm rms (1.2 mm GPS high bias) to a ship-based water vapor radiometer (WVR). We estimate that the vertical position of the GPS antenna in the open ocean was determined to better than 10 cm rms. After correcting for ocean tides GPS estimated sea surface heights from the second cruise compared to the CARIB97 geoid at the 32 cm level in the vertical. Because space based observations of PWV over the oceans generally require cloudless conditions and are accurate to about 5-10% we conclude that ship based GPS observations can provide additional useful meteorological information. Based on the 10-cm vertical position rms and the high horizontal resolution of ship-based positions we further conclude that useful geodetic information can be obtained from high accuracy GPS observations from ships in the open oceans.

  6. Open Ocean Assessments for Management in the GEF Transboundary Waters Assessment Project (TWAP)

    NASA Astrophysics Data System (ADS)

    Fischer, A. S.; Alverson, K. D.

    2010-12-01

    A methodology for a thematic and scientifically-credible assessment of Open Ocean waters as a part of the Global Environment Facility (GEF) Transboundary Waters Assessment Project (TWAP) has been developed in the last 18 months by the Intergovernmental Oceanographic Commission of UNESCO, and is presented for feedback and comment. While developed to help the GEF International Waters focal area target investment to manage looming environmental threats in interlinked freshwater and marine systems (a very focused decision support system), the assessment methodology could contribute to other assessment and management efforts in the UN system and elsewhere. Building on a conceptual framework that describes the relationships between human systems and open ocean natural systems, and on mapping of the human impact on the marine environment, the assessment will evaluate and make projections on a thematic basis, identifying key metrics, indices, and indicators. These themes will include the threats on key ecosystem services of climate change through sea level rise, changed stratification, warming, and ocean acidification; vulnerabilities of ecosystems, habitats, and living marine resources; the impact and sustainability of fisheries; and pollution. Global-level governance arrangements will also be evaluated, with an eye to identifying scope for improved global-level management. The assessment will build on sustained ocean observing systems, model projections, and an assessment of scientific literature, as well as tools for combining knowledge to support identification of priority concerns and in developing scenarios for management. It will include an assessment of key research and observing needs as one way to deal with the scientific uncertainty inherent in such an exercise, and to better link policy and science agendas.

  7. Factors influencing the dissolved iron input by river water to the open ocean

    NASA Astrophysics Data System (ADS)

    Krachler, R.; Jirsa, F.; Ayromlou, S.

    2005-05-01

    The influence of natural metal chelators on the bio-available iron input to the ocean by river water was studied. Ferrous and ferric ions present as suspended colloidal particles maintaining the semblance of a dissolved load are coagulated and settled as their freshwater carrier is mixed with seawater at the continental boundary. However, we might argue that different iron-binding colloids become sequentially destabilized in meeting progressively increasing salinities. By use of a 59Fe tracer method, the partitioning of the iron load from the suspended and dissolved mobile fraction to storage in the sediments was measured with high accuracy in mixtures of natural river water with artificial sea water. The results show a characteristic sequence of sedimentation. Various colloids of different stability are removed from a water of increasing salinity, such as it is the case in the transition from a river water to the open sea. However, the iron transport capacities of the investigated river waters differed greatly. A mountainous river in the Austrian Alps would add only about 5% of its dissolved Fe load, that is about 2.0 µg L-1 Fe, to coastal waters. A small tributary draining a sphagnum peat-bog, which acts as a source of refractory low-molecular-weight fulvic acids to the river water, would add approximately 20% of its original Fe load, that is up to 480 µg L-1 Fe to the ocean's bio-available iron pool. This points to a natural mechanism of ocean iron fertilization by terrigenous fulvic-iron complexes originating from weathering processes occurring in the soils upstream.

  8. Factors influencing the dissolved iron input by river water to the open ocean

    NASA Astrophysics Data System (ADS)

    Krachler, R.; Jirsa, F.; Ayromlou, S.

    The influence of natural metal chelators on the bio-available iron input to the ocean by river water was studied. Ferrous and ferric ions present as suspended colloidal particles maintaining the semblance of a dissolved load are coagulated and settled as their freshwater carrier is mixed with seawater at the continental boundary. However, we might argue that different iron-binding colloids become sequentially destabilized in meeting progressively increasing salinities. By use of a 59Fe tracer method, the partitioning of the iron load from the suspended and dissolved mobile fraction to storage in the sediments was measured with high accuracy in mixtures of natural river water with artificial sea water. The results show a characteristic sequence of sedimentation. Various colloids of different stability are removed from a water of increasing salinity, such as it is the case in the transition from a river water to the open sea. However, the iron transport capacities of the investigated river waters differed greatly. A mountainous river in the Austrian Alps would add only about 5% of its dissolved Fe load, that is about 2.0 µg L-1 Fe, to coastal waters. A small tributary draining a sphagnum peat-bog, which acts as a source of refractory low-molecular-weight fulvic acids to the river water, would add approximately 20% of its original Fe load, that is up to 480 µg L-1 Fe to the ocean's bio-available iron pool. This points to a natural mechanism of ocean iron fertilization by terrigenous fulvic-iron complexes originating from weathering processes occurring in the soils upstream.

  9. Sensitivity of Calibration Gains to Ocean Color Processing in Coastal and Open Waters Using Ensembles Members for NPP-VIIRS

    DTIC Science & Technology

    2014-07-01

    blue and green water gain and determine the impact on products in the Gulf of Mexico which represents a wide variety of water types from open ocean to...because if is available daily. Figure 1 - The green water gains were computed from the WaveCis AERONET site in the Northern Gulf of Mexico from...These gains were applied to several Gulf of Mexico scenes however and the derived ocean color products evaluated. . ,./-■ _’^iifew;fr

  10. Respiration in the open ocean.

    PubMed

    del Giorgio, Paul A; Duarte, Carlos M

    2002-11-28

    A key question when trying to understand the global carbon cycle is whether the oceans are net sources or sinks of carbon. This will depend on the production of organic matter relative to the decomposition due to biological respiration. Estimates of respiration are available for the top layers, the mesopelagic layer, and the abyssal waters and sediments of various ocean regions. Although the total open ocean respiration is uncertain, it is probably substantially greater than most current estimates of particulate organic matter production. Nevertheless, whether the biota act as a net source or sink of carbon remains an open question.

  11. Influence of open ocean nitrogen supply on the skeletal δ15N of modern shallow-water scleractinian corals

    NASA Astrophysics Data System (ADS)

    Wang, Xingchen T.; Sigman, Daniel M.; Cohen, Anne L.; Sinclair, Daniel J.; Sherrell, Robert M.; Cobb, Kim M.; Erler, Dirk V.; Stolarski, Jarosław; Kitahara, Marcelo V.; Ren, Haojia

    2016-05-01

    The isotopic composition of skeleton-bound organic nitrogen in shallow-water scleractinian corals (hereafter, CS-δ15N) is an emerging tool for studying the marine nitrogen cycle in the past. The CS-δ15N has been shown to reflect the δ15N of nitrogen (N) sources to corals, with most applications to date focusing on the anthropogenic/terrestrial N inputs to reef environments. However, many coral reefs receive their primary N sources from the open ocean, and the CS-δ15N of these corals may provide information on past changes in the open ocean regional and global N cycle. Using a recently developed persulfate/denitrifier-based method, we measured CS-δ15N in modern shallow-water scleractinian corals from 8 sites proximal to the open ocean. At sites with low open ocean surface nitrate concentrations typical of the subtropics and tropics, measured CS-δ15N variation on seasonal and annual timescales is most often less than 2‰. In contrast, a broad range in CS-δ15N (of ∼10‰) is measured across these sites, with a strong correlation between CS-δ15N and the δ15N of the deep nitrate supply to the surface waters near the reefs. While CS-δ15N can be affected by other N sources as well and can vary in response to local reef conditions as well as coral/symbiont physiological changes, this survey indicates that, when considering corals proximal to the open ocean, the δ15N of the subsurface nitrate supply to surface waters drives most of the CS-δ15N variation across the global ocean. Thus, CS-δ15N is a promising proxy for reconstructing the open ocean N cycle in the past.

  12. Sensitivity of open-water ice growth and ice concentration evolution in a coupled atmosphere-ocean-sea ice model

    NASA Astrophysics Data System (ADS)

    Shi, Xiaoxu; Lohmann, Gerrit

    2017-09-01

    A coupled atmosphere-ocean-sea ice model is applied to investigate to what degree the area-thickness distribution of new ice formed in open water affects the ice and ocean properties. Two sensitivity experiments are performed which modify the horizontal-to-vertical aspect ratio of open-water ice growth. The resulting changes in the Arctic sea-ice concentration strongly affect the surface albedo, the ocean heat release to the atmosphere, and the sea-ice production. The changes are further amplified through a positive feedback mechanism among the Arctic sea ice, the Atlantic Meridional Overturning Circulation (AMOC), and the surface air temperature in the Arctic, as the Fram Strait sea ice import influences the freshwater budget in the North Atlantic Ocean. Anomalies in sea-ice transport lead to changes in sea surface properties of the North Atlantic and the strength of AMOC. For the Southern Ocean, the most pronounced change is a warming along the Antarctic Circumpolar Current (ACC), owing to the interhemispheric bipolar seasaw linked to AMOC weakening. Another insight of this study lies on the improvement of our climate model. The ocean component FESOM is a newly developed ocean-sea ice model with an unstructured mesh and multi-resolution. We find that the subpolar sea-ice boundary in the Northern Hemisphere can be improved by tuning the process of open-water ice growth, which strongly influences the sea ice concentration in the marginal ice zone, the North Atlantic circulation, salinity and Arctic sea ice volume. Since the distribution of new ice on open water relies on many uncertain parameters and the knowledge of the detailed processes is currently too crude, it is a challenge to implement the processes realistically into models. Based on our sensitivity experiments, we conclude a pronounced uncertainty related to open-water sea ice growth which could significantly affect the climate system sensitivity.

  13. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2014-06-09

    sea spray over the open ocean and the severity of sea spray icing on fixed offshore structures. We will use existing information on the relationship...and the resulting spray icing on offshore structures, such as wind turbines and exploration, drilling , and production platforms. Our approach...International Ocean ( Offshore ) and Polar Engineering Conference, Anchorage, AK, 30 June–5 July 2013, International Society of Offshore and Polar

  14. Genome Sequence of the Marine Bacterium Vibrio campbellii DS40M4, Isolated from Open Ocean Water

    PubMed Central

    Dias, Graciela M.; Thompson, Cristiane C.; Fishman, Brian; Naka, Hiroaki; Haygood, Margo G.; Crosa, Jorge H.

    2012-01-01

    Vibrio sp. strain DS40M4 is a marine bacterium that was isolated from open ocean water. In this work, using genomic taxonomy, we were able to classify this bacterium as V. campbellii. Our genomic analysis revealed that V. campbellii DS40M4 harbors genes related to iron transport, virulence, and environmental fitness, such as those encoding anguibactin and vanchrobactin biosynthesis proteins, type II, III, IV, and VI secretion systems, and proteorhodopsin. PMID:22275102

  15. Undocumented water column sink for cadmium in open ocean oxygen-deficient zones

    PubMed Central

    Janssen, David J.; Conway, Tim M.; John, Seth G.; Christian, James R.; Kramer, Dennis I.; Pedersen, Tom F.; Cullen, Jay T.

    2014-01-01

    Cadmium (Cd) is a micronutrient and a tracer of biological productivity and circulation in the ocean. The correlation between dissolved Cd and the major algal nutrients in seawater has led to the use of Cd preserved in microfossils to constrain past ocean nutrient distributions. However, linking Cd to marine biological processes requires constraints on marine sources and sinks of Cd. Here, we show a decoupling between Cd and major nutrients within oxygen-deficient zones (ODZs) in both the Northeast Pacific and North Atlantic Oceans, which we attribute to Cd sulfide (CdS) precipitation in euxinic microenvironments around sinking biological particles. We find that dissolved Cd correlates well with dissolved phosphate in oxygenated waters, but is depleted compared with phosphate in ODZs. Additionally, suspended particles from the North Atlantic show high Cd content and light Cd stable isotope ratios within the ODZ, indicative of CdS precipitation. Globally, we calculate that CdS precipitation in ODZs is an important, and to our knowledge a previously undocumented marine sink of Cd. Our results suggest that water column oxygen depletion has a substantial impact on Cd biogeochemical cycling, impacting the global relationship between Cd and major nutrients and suggesting that Cd may be a previously unidentified tracer for water column oxygen deficiency on geological timescales. Similar depletions of copper and zinc in the Northeast Pacific indicate that sulfide precipitation in ODZs may also have an influence on the global distribution of other trace metals. PMID:24778239

  16. Undocumented water column sink for cadmium in open ocean oxygen-deficient zones.

    PubMed

    Janssen, David J; Conway, Tim M; John, Seth G; Christian, James R; Kramer, Dennis I; Pedersen, Tom F; Cullen, Jay T

    2014-05-13

    Cadmium (Cd) is a micronutrient and a tracer of biological productivity and circulation in the ocean. The correlation between dissolved Cd and the major algal nutrients in seawater has led to the use of Cd preserved in microfossils to constrain past ocean nutrient distributions. However, linking Cd to marine biological processes requires constraints on marine sources and sinks of Cd. Here, we show a decoupling between Cd and major nutrients within oxygen-deficient zones (ODZs) in both the Northeast Pacific and North Atlantic Oceans, which we attribute to Cd sulfide (CdS) precipitation in euxinic microenvironments around sinking biological particles. We find that dissolved Cd correlates well with dissolved phosphate in oxygenated waters, but is depleted compared with phosphate in ODZs. Additionally, suspended particles from the North Atlantic show high Cd content and light Cd stable isotope ratios within the ODZ, indicative of CdS precipitation. Globally, we calculate that CdS precipitation in ODZs is an important, and to our knowledge a previously undocumented marine sink of Cd. Our results suggest that water column oxygen depletion has a substantial impact on Cd biogeochemical cycling, impacting the global relationship between Cd and major nutrients and suggesting that Cd may be a previously unidentified tracer for water column oxygen deficiency on geological timescales. Similar depletions of copper and zinc in the Northeast Pacific indicate that sulfide precipitation in ODZs may also have an influence on the global distribution of other trace metals.

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

    NASA Astrophysics Data System (ADS)

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

    2017-05-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

  19. Inherent optical properties and satellite retrieval of chlorophyll concentration in the lagoon and open ocean waters of New Caledonia.

    PubMed

    Dupouy, Cécile; Neveux, Jacques; Ouillon, Sylvain; Frouin, Robert; Murakami, Hiroshi; Hochard, Sébastien; Dirberg, Guillaume

    2010-01-01

    The retrieval of chlorophyll-a concentration from remote sensing reflectance (Rrs) data was tested with the NASA OC4v4 algorithm on the inner New Caledonian lagoon (Case 2) and adjacent open ocean (Case 1) waters. The input to OC4v4 was Rrs measured in situ or modeled from water's inherent optical properties (2001-2007). At open ocean stations, backscattering and absorption coefficients were correlated with chlorophyll (R(2)=0.31-0.51, respectively), in agreement with models for Case 1 waters. Taking spectrofluorometric measurement as reference, the OC4v4 model leads to an average underestimation of 33% of the chlorophyll concentration. For the lagoon waters, OC4v4 performed inadequately because the backscattering coefficient, highly correlated with turbidity and suspended matter (R(2)=0.98), was poorly correlated to chlorophyll (R(2)=0.42). The OC4v4 performance was better in deep lagoon waters for stations with a TDT index (Tchla x depth/turbidity) higher than 19 mg m(-2) NTU(-1) (R(2)=0.974, bias=10.2%). Global Imager Rrs provided a good estimate of Tchla (R(2)=0.79, N=28) in the deeper part of the lagoon. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  20. Relationship between abundance and specific activity of bacterioplankton in open ocean surface waters.

    PubMed

    Hunt, Dana E; Lin, Yajuan; Church, Matthew J; Karl, David M; Tringe, Susannah G; Izzo, Lisa K; Johnson, Zackary I

    2013-01-01

    Marine microbial communities are complex and dynamic, and their ecology impacts biogeochemical cycles in pelagic ecosystems. Yet, little is known about the relative activities of different microbial populations within genetically diverse communities. We used rRNA as a proxy for activity to quantify the relative specific activities (rRNA/ribosomal DNA [rDNA or rRNA genes]) of the eubacterial populations and to identify locations or clades for which there are uncouplings between specific activity and abundance. After analyzing 1.6 million sequences from 16S rDNA and rRNA (cDNA) libraries from two euphotic depths from a representative site in the Pacific Ocean, we show that although there is an overall positive relationship between the abundances (rDNAs) and activities (rRNAs) among populations of the bacterial community, for some populations these measures are uncoupled. Different ecological strategies are exemplified by the two numerically dominant clades at this site: the cyanobacterium Prochlorococcus is abundant but disproportionately more active, while the heterotrophic SAR11 is abundant but less active. Other rare populations, such as Alteromonas, have high specific activities in spite of their low abundances, suggesting intense population regulation. More detailed analyses using a complementary quantitative PCR (qPCR)-based approach of measuring relative specific activity for Prochlorococcus populations in the Pacific and Atlantic Oceans also show that specific activity, but not abundance, reflects the key drivers of light and nutrients in this system; our results also suggest substantial top-down regulation (e.g., grazing, viruses, or organismal interactions) or transport (e.g., mixing, immigration, or emigration) of these populations. Thus, we show here that abundance and specific activity can be uncoupled in open ocean systems and that describing both is critical to characterizing microbial communities and predicting marine ecosystem functioning and

  1. Open ocean tide modelling

    NASA Technical Reports Server (NTRS)

    Parke, M. E.

    1978-01-01

    Two trends evident in global tidal modelling since the first GEOP conference in 1972 are described. The first centers on the incorporation of terms for ocean loading and gravitational self attraction into Laplace's tidal equations. The second centers on a better understanding of the problem of near resonant modelling and the need for realistic maps of tidal elevation for use by geodesists and geophysicists. Although new models still show significant differences, especially in the South Atlantic, there are significant similarities in many of the world's oceans. This allows suggestions to be made for future locations for bottom pressure gauge measurements. Where available, estimates of M2 tidal dissipation from the new models are significantly lower than estimates from previous models.

  2. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2013-09-30

    affects the heat and mass transfer across the air-sea interface, which in turn influences climatology. Global climate models are sensitive to changes in...western 7 Bering Sea near Siberia , and off the coast of southwest Alaska, including Cook Inlet, where the semi- submersible Ocean Bounty...sea spray climatology in the Arctic Ocean to change with the declining sea ice cover. • The evaporation of the drops in the marine boundary layer

  3. An Autonomous Mobile Platform for Underway Surface Carbon Measurements in Open-Ocean and Coastal Waters

    DTIC Science & Technology

    2010-06-01

    make it challenging to evaluate global fluxes based on in situ measurements alone. The latest global flux climatology , based on approximately three...circulation/biogeochemical models). They found that these different approaches, including the Takahashi climatologies , are consistent within their...outside of these routes. B. Coastal Ocean Carbon Data Limitations Another limitation of the global CO2 climatology is that it explicitly excludes

  4. Human impacts on open ocean mercury concentrations

    NASA Astrophysics Data System (ADS)

    Sunderland, Elsie M.; Mason, Robert P.

    2007-12-01

    We develop an empirically constrained multicompartment box model for mercury cycling in open ocean regions to investigate changes in concentrations resulting from anthropogenic perturbations of the global mercury cycle. Using Monte Carlo simulations, we explicitly consider the effects of variability in measured parameters on modeled seawater concentrations. Our simulations show that anthropogenic enrichment in all surface (25%) and deep ocean waters (11%) is lower than global atmospheric enrichment (300-500%) and varies considerably among geographic regions, ranging from >60% in parts of the Atlantic and Mediterranean to <1% in the deep Pacific. Model results indicate that open ocean mercury concentrations do not rapidly equilibrate with atmospheric deposition and on average will increase if anthropogenic emissions remain at their present level. We estimate the temporal lag between changes in atmospheric deposition and ocean mercury concentrations will vary from decades in most of the Atlantic up to centuries in parts of the Pacific.

  5. Contribution of water-leaving radiances to multiangle, multispectral polarimetric observations over the open ocean: bio-optical model results for case 1 waters

    NASA Astrophysics Data System (ADS)

    Chowdhary, Jacek; Cairns, Brian; Travis, Larry D.

    2006-08-01

    Multiangle, multispectral photopolarimetry of atmosphere-ocean systems provides the fullest set of remote sensing information possible on the scattering properties of aerosols and on the color of the ocean. Recent studies have shown that inverting such data allows for the potential of separating the retrieval of aerosol properties from ocean color monitoring in the visible part of the spectrum. However, the data in these studies were limited to those principal plane observations where the polarization of water-leaving radiances could be ignored. Examining similar potentials for off-principal plane observations requires the ability to assess realistic variations in both the reflectance for and bidirectionality of polarized water-leaving radiances for such viewing geometries. We provide hydrosol models for use in underwater light scattering computations to study such variations. The model consists of two components whose refractive indices resemble those of detritus-minerallike and planktonlike particles, whose size distributions are constrained by underwater light linear polarization signatures, and whose mixing ratios change as a function of particulate backscattering efficiency. Multiple scattering computations show that these models are capable of reproducing realistic underwater light albedos for wavelengths ranging from 400 to 600 nm, and for chlorophyll a concentrations ranging from 0.03 to 3.0 mg/m3. Numerical results for spaceborne observations of the reflectance for total and polarized water-leaving radiances are provided as a function of polar angles, and the change in these reflectances with wavelength, chlorophyll a concentration, and hydrosol model are discussed in detail for case 1 (open ocean) waters.

  6. Contribution of water-leaving radiances to multiangle, multispectral polarimetric observations over the open ocean: bio-optical model results for case 1 waters.

    PubMed

    Chowdhary, Jacek; Cairns, Brian; Travis, Larry D

    2006-08-01

    Multiangle, multispectral photopolarimetry of atmosphere-ocean systems provides the fullest set of remote sensing information possible on the scattering properties of aerosols and on the color of the ocean. Recent studies have shown that inverting such data allows for the potential of separating the retrieval of aerosol properties from ocean color monitoring in the visible part of the spectrum. However, the data in these studies were limited to those principal plane observations where the polarization of water-leaving radiances could be ignored. Examining similar potentials for off-principal plane observations requires the ability to assess realistic variations in both the reflectance for and bidirectionality of polarized water-leaving radiances for such viewing geometries. We provide hydrosol models for use in underwater light scattering computations to study such variations. The model consists of two components whose refractive indices resemble those of detritus-minerallike and planktonlike particles, whose size distributions are constrained by underwater light linear polarization signatures, and whose mixing ratios change as a function of particulate backscattering efficiency. Multiple scattering computations show that these models are capable of reproducing realistic underwater light albedos for wavelengths ranging from 400 to 600 nm, and for chlorophyll a concentrations ranging from 0.03 to 3.0 mg/m(3). Numerical results for spaceborne observations of the reflectance for total and polarized water-leaving radiances are provided as a function of polar angles, and the change in these reflectances with wavelength, chlorophyll a concentration, and hydrosol model are discussed in detail for case 1 (open ocean) waters.

  7. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2013-06-17

    carbon dioxide sensor, and an Ophir hygrometer /thermometer on a “turbulence” tripod near the northeast shore of the island (Figure 4). 5 Figure 3...turbulence” tripod with its sonic anemometer/thermometer, carbon dioxide and water vapor sensor, and hygrometer /thermometer deployed near the shore of

  8. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2015-06-12

    We anticipate that structures placed in shallow water—wind turbines , drilling rigs, or man-made production islands, for instance—will, therefore...anticipate that structures placed in shallow water???wind turbines , drilling rigs, or man-made production islands, for instance???will, therefore...concentrations of wind-generated sea spray and the resulting spray icing on offshore structures, such as wind turbines and exploration, drilling, and

  9. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2012-09-30

    spray ice density data. Our second spray instrument will be a cloud imaging probe with an optical array. It photographs and then automatically sizes...third moment of the drop concentration from the cloud imaging probe is the spray liquid water content. Hence, the combination of the two instruments...working with Edgar Andreas at NWRA. We are borrowing Chris Fairall’s cloud imaging probe. The data for the spray climatologies come from the National

  10. Sea Spray and Icing in the Emerging Open Water of the Arctic Ocean

    DTIC Science & Technology

    2012-09-30

    spray instrument will be a cloud imaging probe, which we are borrowing from Chris Fairall at NOAA/ESRL. This device consists of an optical array; it...each 25 µm wide. The integral of the third moment of the drop concentration from the cloud imaging probe is the spray liquid water content. Hence...Gloersen P, Zwally HJ. 1996. updated yearly. Sea Ice Concentrations from Nimbus -7 SMMR and DMSP SSM/I-SSMIS Passive Microwave Data, October 1979. Boulder

  11. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2016-10-07

    OASIS, INC. 1 Report No. QSR-14C0172- Ocean Acoustics-093016 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics...Award No.: N00014-14-C-0172 Report No. QSR-14C0172- Ocean Acoustics-093016 Prepared for: Office of Naval Research For the period: July 1, 2016...to September 30, 2016 Submitted by: Principal Investigator/Author: Kevin Heaney Ocean Acoustical Services and Instrumentation Systems, Inc. 5

  12. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2016-08-03

    OASIS, INC. 1 Report No. QSR-14C0172- Ocean Acoustics-063016 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics...Award No.: N00014-14-C-0172 Report No. QSR-14C0172- Ocean Acoustics-063016 Prepared for: Office of Naval Research For the period: April 1...2016 to June 30, 2016 Submitted by: Principal Investigator/Author: Kevin Heaney Ocean Acoustical Services and Instrumentation Systems, Inc. 5

  13. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2016-04-30

    OASIS, INC. 1 Report No. QSR-14C0172- Ocean Acoustics-043016 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics...Award No.: N00014-14-C-0172 Report No. QSR-14C0172- Ocean Acoustics-093015 Prepared for: Office of Naval Research For the period: January 1...2016 to March 31, 2015 Submitted by: Principal Investigator/Author: Kevin Heaney Ocean Acoustical Services and Instrumentation Systems, Inc. 5

  14. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2015-07-17

    under-ice scattering , bathymetric diffraction and the application of the ocean acoustic Parabolic Equation to infrasound. 2. Tasks a. Task 1...QSR-14C0172-Ocean Acoustics -063015 Figure 10. Estimated reflection coefficient as a function of frequency by taking the difference of downgoing and...OASIS, INC. 1 Report No. QSR-14C0172-Ocean Acoustics -063015 Quarterly Progress Report Technical and Financial Deep Water Ocean Acoustics

  15. Evasion of mercury from coastal and open waters of the Atlantic Ocean and the Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Gårdfeldt, Katarina; Sommar, Jonas; Ferrara, Romano; Ceccarini, Claudia; Lanzillotta, Enrica; Munthe, John; Wängberg, Ingvar; Lindqvist, Oliver; Pirrone, Nicola; Sprovieri, Francesca; Pesenti, Eduardo; Strömberg, Dan

    Dissolved gaseous mercury (DGM) was measured in coastal Atlantic seawater and in the Mediterranean Sea. The Atlantic measurements were performed during September 1999 at the Mace Head Atmospheric Research Station, situated on the Irish west coast. The measurements in the Mediterranean Sea were made along a 6000 km cruise path from 14 July to 9 August 2000 in the framework of the Med-Oceanor project. Total gaseous mercury (TGM) concentrations in air were continuously measured with a 5 min time resolution using an automated mercury analyser (Tekran 2537A) during both expeditions. Paired TGM and DGM samples from all campaigns showed that the surface water was supersaturated with elemental mercury. The mercury evasion was estimated using a gas exchange model (J. Geophys. Res. 97 (1992) 7373), which uses salinity, wind speed and water temperature as independent parameters. The predicted average mercury evasion from the coastal Atlantic water was 2.7 ng m -2 h -1 implying that the concentration of TGM in the Atlantic air is enhanced by mercury evasion from the sea. Measurements in different regions of the Mediterranean Sea showed spatial variations in DGM concentrations. The highest DGM concentration (˜90 pg l -1) was observed at a location in the Strait of Sicily (37°16N 11°52E). The mercury evasion in the eastern sector of the Mediterranean Sea (area: 32-36°N, 17-28°E) was generally higher (7.9 ng m -2 h -1) than that observed in the Tyrrhenian Sea (4.2 ng m -2 h -1) or in the western sector (2.5 ng m -2 h -1) (areas: 38-42°N, 8-13°E and 38-41°N, 7-8°E, respectively). Estimations of mercury evasion were also made at Mediterranean coastal sites using a dynamic chamber technique. In addition, a newly developed method making continuous in situ DGM measurements possible was tested.

  16. Patterns of Genetic Diversity and Co-Existence in Open Ocean Diatoms: the Effects of Water Mass Structure, Selection and Sex

    NASA Astrophysics Data System (ADS)

    Rynearson, T. A.; Chen, G.

    2016-02-01

    The open ocean North Atlantic spring bloom influences regional ecology and global biogeochemistry. Diatoms dominate the peak of the bloom and significantly impact productivity and export of organic carbon from the bloom. Despite their key role in a yearly event with global impacts, the genetic diversity and population structure of diatoms that comprise this open ocean bloom are unknown. Here we investigated the population genetics of the diatom Thalassiosira gravida sampled during the 2008 North Atlantic Bloom Experiment using newly-developed microsatellite markers. Here, we show that the genetic diversity of open ocean diatoms is high and that their population structure differs dramatically from coastal diatoms. High levels of genetic diversity were observed across all water samples and did not change during the bloom. Four genetically distinct populations were identified but were not associated with different water masses, depths or time points during the bloom. Instead, all four populations co-existed within samples, spanning different water masses, stages of the bloom and depths of over >300 m. The pattern of genetically distinct, co-existing populations in the open ocean contrasts dramatically with coastal habitats, where distinct populations have not been observed to co-exist at the same time and place. It is likely that populations originate via transport from disparate locations combined with overwintering capacity in the water column or sediments. The pattern of co-existence suggests that the open ocean may serve as a gene pool that harbors different populations that are then available for selection to act upon, which may contribute to the ecological and biogeochemical success of diatoms and influence their long-term evolutionary survival.

  17. Deep Water Ocean Acoustics

    DTIC Science & Technology

    2016-12-22

    Final Report 3. DATES COVERED (From - To) 7/1/15 to 12/22/16 4. TITLE AND SUBTITLE Deep Water Ocean Acoustics 5a. CONTRACT NUMBER...NUMBER Ocean Acoustical Services and Instrumentation Systems, Inc. 5 Militia Drive, Ste. 104 Lexington, MA 02421-4706...FR-14C0172- Ocean Acoustics- 123116 9. SPONSORING / MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR’S ACRONYM(S) Office of Naval

  18. Invariance of polarized reflectance measured at the top of atmosphere by PARASOL satellite instrument in the visible range with marine constituents in open ocean waters.

    PubMed

    Harmel, Tristan; Chami, Malik

    2008-04-28

    The influence of oceanic constituents on the polarized reflectance measured at the top of atmosphere (TOA) over open ocean waters in one visible band is investigated. First, radiative transfer modelling is used to quantify the effects of biomass concentration on the TOA polarized signal for a wide range of observation geometries. The results showed that the TOA polarized reflectance remains insensitive to variations in the chlorophyll a concentration whatever the geometrical conditions in oligotrophic and mesotrophic waters, which represent about 90% of the global ocean. The invariance of the polarized signal with water content is explained by the prevailing influence of both atmospheric effects and skylight reflections at the sea surface on the polarization state of the radiation reaching the top of atmosphere level. The simulations also revealed that multidirectional and polarized TOA reflectances obtained in the visible spectrum are powerful tools for the discrimination between the aerosol optical properties. In the second part of the paper, the theoretical results are rigorously validated using original multiangle and polarized measurements acquired by PARASOL satellite sensor, which is used for the first time for ocean color purposes. First, a statistical analysis of the geometrical features of PARASOL instrument showed that the property of invariance of the TOA polarized reflectance is technically verified for more than 85% of viewed targets, and thus, indicating the feasibility of separating between the atmospheric and oceanic parameters from space remotely sensed polarized data. Second, PARASOL measurements acquired at regional and global scales nicely corroborated the simulations. This study also highlighted that the radiometric performance of the polarized visible wavelength of PARASOL satellite sensor can be used either for the aerosol detection or for atmospheric correction algorithms over open ocean waters regardless of the biomass concentration.

  19. Sensitivity of Multiangle, Multispectral Polarimetric Remote Sensing Over Open Oceans to Water-Leaving Radiance: Analyses of RSP Data Acquired During the MILAGRO Campaign

    NASA Technical Reports Server (NTRS)

    Chowdhary, Jacek; Cairns, Brian; Waquet, Fabien; Knobelspiesse, Kirk; Ottaviani, Matteo; Redemann, Jens; Travis, Larry; Mishchenko, Michael

    2012-01-01

    For remote sensing of aerosol over the ocean, there is a contribution from light scattered underwater. The brightness and spectrum of this light depends on the biomass content of the ocean, such that variations in the color of the ocean can be observed even from space. Rayleigh scattering by pure sea water, and Rayleigh-Gans type scattering by plankton, causes this light to be polarized with a distinctive angular distribution. To study the contribution of this underwater light polarization to multiangle, multispectral observations of polarized reflectance over ocean, we previously developed a hydrosol model for use in underwater light scattering computations that produces realistic variations of the ocean color and the underwater light polarization signature of pure sea water. In this work we review this hydrosol model, include a correction for the spectrum of the particulate scattering coefficient and backscattering efficiency, and discuss its sensitivity to variations in colored dissolved organic matter (CDOM) and in the scattering function of marine particulates. We then apply this model to measurements of total and polarized reflectance that were acquired over open ocean during the MILAGRO field campaign by the airborne Research Scanning Polarimeter (RSP). Analyses show that our hydrosol model faithfully reproduces the water-leaving contributions to RSP reflectance, and that the sensitivity of these contributions to Chlorophyll a concentration [Chl] in the ocean varies with the azimuth, height, and wavelength of observations. We also show that the impact of variations in CDOM on the polarized reflectance observed by the RSP at low altitude is comparable to or much less than the standard error of this reflectance whereas their effects in total reflectance may be substantial (i.e. up to >30%). Finally, we extend our study of polarized reflectance variations with [Chl] and CDOM to include results for simulated spaceborne observations.

  20. Open cycle ocean thermal energy conversion system

    DOEpatents

    Wittig, J. Michael

    1980-01-01

    An improved open cycle ocean thermal energy conversion system including a flash evaporator for vaporizing relatively warm ocean surface water and an axial flow, elastic fluid turbine having a vertical shaft and axis of rotation. The warm ocean water is transmitted to the evaporator through a first prestressed concrete skirt-conduit structure circumferentially situated about the axis of rotation. The unflashed warm ocean water exits the evaporator through a second prestressed concrete skirt-conduit structure located circumferentially about and radially within the first skirt-conduit structure. The radially inner surface of the second skirt conduit structure constitutes a cylinder which functions as the turbine's outer casing and obviates the need for a conventional outer housing. The turbine includes a radially enlarged disc element attached to the shaft for supporting at least one axial row of radially directed blades through which the steam is expanded. A prestressed concrete inner casing structure of the turbine has upstream and downstream portions respectively situated upstream and downstream from the disc element. The radially outer surfaces of the inner casing portions and radially outer periphery of the axially interposed disc cooperatively form a downwardly radially inwardly tapered surface. An annular steam flowpath of increasing flow area in the downward axial direction is radially bounded by the inner and outer prestressed concrete casing structures. The inner casing portions each include a transversely situated prestressed concrete circular wall for rotatably supporting the turbine shaft and associated structure. The turbine blades are substantially radially coextensive with the steam flowpath and receive steam from the evaporator through an annular array of prestressed concrete stationary vanes which extend between the inner and outer casings to provide structural support therefor and impart a desired flow direction to the steam.

  1. A novel isotopic fractionation during dissolved oxygen consumption in mesopelagic waters inferred from observation and model simulation of dissolved oxygen δ18O in open oceanic regions

    NASA Astrophysics Data System (ADS)

    Nakayama, N.; Oka, A.; Gamo, T.

    2012-12-01

    Oxygen isotopic ratio (δ18O) of dissolved oxygen is a useful for bioactive tracer of the subsurface aphotic (mesopelagic) ocean since it varies nonlinearly related to oxygen consumption via stoichiometry of organic matter decomposition. Therefore, along with global circulation model (GCM), observed δ18O and their vertical/geographical distribution can be effectively used to quantitatively determine how marine biological and ocean physical processes contribute to varying dissolved oxygen (DO) concentration in the ocean, in particular mesopelagic zone where pronounced biological activity alters DO concentration significantly. In the central north Pacific Ocean and Indian Ocean, including Arabian Sea, one of the few regions in the open ocean which has oxygen minimum zone (OMZ, a layer with severely depleted DO), vertical profiles of DO and δ18O were observed. These observed data are compared with a GCM simulation in which a constant isotopic fractionation factor of DO by marine biological respiration and a fixed Redfield molar ratio between P and O are assumed. Even in the Arabian Sea OMZ, relationship between DO and δ18O was found to be similar to those observed in other open oceans, indicating that no specific oxygen consumption process occurred in the OMZ. Using the GCM model, we attempted to reproduce the observed overall relationship between DO and δ18O, but it failed when we adopted the previously reported isotopic fractionation factor: Discrepancy became larger when oxygen saturation level decreased, in particular in thermocline water (at 20% oxygen saturation level, modeled δ18O was heavier than observed values by +7‰). Sensitivity simulations with the GCM model revealed that (1) simply changing the intensity of oxygen consumption by respiration/organic matter decomposition nor physical processes (diffusion and/or advection) could explain the observed relationship between DO and δ18O, (2) applying a smaller isotopic fractionation for deep waters

  2. Optimizing Ocean Space: Co-siting Open Ocean Aquaculture

    NASA Astrophysics Data System (ADS)

    Cobb, B. L.; Wickliffe, L. C.; Morris, J. A., Jr.

    2016-12-01

    In January of 2016, NOAA's National Marine Fisheries Service released the Gulf Aquaculture Plan (GAP) to manage the development of environmentally sound and economically sustainable open ocean finfish aquaculture in the Gulf of Mexico (inside the U.S. Exclusive Economic Zone [EEZ]). The GAP provides the first regulatory framework for aquaculture in federal waters with estimated production of 64 million pounds of finfish, and an estimated economic impact of $264 million annually. The Gulf of Mexico is one of the most industrialized ocean basins in the world, with many existing ocean uses including oil and natural gas production, shipping and commerce, commercial fishing operations, and many protected areas to ensure conservation of valuable ecosystem resources and services. NOAA utilized spatial planning procedures and tools identifying suitable sites for establishing aquaculture through exclusion analyses using authoritative federal and state data housed in a centralized geodatabase. Through a highly collaborative, multi-agency effort a mock permitting exercise was conducted to illustrate the regulatory decision-making process for the Gulf. Further decision-making occurred through exploring co-siting opportunities with oil and natural gas platforms. Logistical co-siting was conducted to reduce overall operational costs by looking at distance to major port and commodity tonnage at each port. Importantly, the process of co-siting allows aquaculture to be coupled with other benefits, including the availability of previously established infrastructure and the reduction of environmental impacts.

  3. Open ocean dead zones in the tropical North Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Karstensen, J.; Fiedler, B.; Schütte, F.; Brandt, P.; Körtzinger, A.; Fischer, G.; Zantopp, R.; Hahn, J.; Visbeck, M.; Wallace, D.

    2015-04-01

    Here we present first observations, from instrumentation installed on moorings and a float, of unexpectedly low (<2 μmol kg-1) oxygen environments in the open waters of the tropical North Atlantic, a region where oxygen concentration does normally not fall much below 40 μmol kg-1. The low-oxygen zones are created at shallow depth, just below the mixed layer, in the euphotic zone of cyclonic eddies and anticyclonic-modewater eddies. Both types of eddies are prone to high surface productivity. Net respiration rates for the eddies are found to be 3 to 5 times higher when compared with surrounding waters. Oxygen is lowest in the centre of the eddies, in a depth range where the swirl velocity, defining the transition between eddy and surroundings, has its maximum. It is assumed that the strong velocity at the outer rim of the eddies hampers the transport of properties across the eddies boundary and as such isolates their cores. This is supported by a remarkably stable hydrographic structure of the eddies core over periods of several months. The eddies propagate westward, at about 4 to 5 km day-1, from their generation region off the West African coast into the open ocean. High productivity and accompanying respiration, paired with sluggish exchange across the eddy boundary, create the "dead zone" inside the eddies, so far only reported for coastal areas or lakes. We observe a direct impact of the open ocean dead zones on the marine ecosystem as such that the diurnal vertical migration of zooplankton is suppressed inside the eddies.

  4. Plastic debris in the open ocean

    PubMed Central

    Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J. Ignacio; Irigoien, Xabier; Úbeda, Bárbara; Hernández-León, Santiago; Palma, Álvaro T.; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L.; Duarte, Carlos M.

    2014-01-01

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean. PMID:24982135

  5. Plastic debris in the open ocean.

    PubMed

    Cózar, Andrés; Echevarría, Fidel; González-Gordillo, J Ignacio; Irigoien, Xabier; Ubeda, Bárbara; Hernández-León, Santiago; Palma, Alvaro T; Navarro, Sandra; García-de-Lomas, Juan; Ruiz, Andrea; Fernández-de-Puelles, María L; Duarte, Carlos M

    2014-07-15

    There is a rising concern regarding the accumulation of floating plastic debris in the open ocean. However, the magnitude and the fate of this pollution are still open questions. Using data from the Malaspina 2010 circumnavigation, regional surveys, and previously published reports, we show a worldwide distribution of plastic on the surface of the open ocean, mostly accumulating in the convergence zones of each of the five subtropical gyres with comparable density. However, the global load of plastic on the open ocean surface was estimated to be on the order of tens of thousands of tons, far less than expected. Our observations of the size distribution of floating plastic debris point at important size-selective sinks removing millimeter-sized fragments of floating plastic on a large scale. This sink may involve a combination of fast nano-fragmentation of the microplastic into particles of microns or smaller, their transference to the ocean interior by food webs and ballasting processes, and processes yet to be discovered. Resolving the fate of the missing plastic debris is of fundamental importance to determine the nature and significance of the impacts of plastic pollution in the ocean.

  6. Impact of an intense water column mixing (0-1500 m) on prokaryotic diversity and activities during an open-ocean convection event in the NW Mediterranean Sea.

    PubMed

    Severin, Tatiana; Sauret, Caroline; Boutrif, Mehdi; Duhaut, Thomas; Kessouri, Fayçal; Oriol, Louise; Caparros, Jocelyne; Pujo-Pay, Mireille; Durrieu de Madron, Xavier; Garel, Marc; Tamburini, Christian; Conan, Pascal; Ghiglione, Jean-François

    2016-12-01

    Open-ocean convection is a fundamental process for thermohaline circulation and biogeochemical cycles that causes spectacular mixing of the water column. Here, we tested how much the depth-stratified prokaryotic communities were influenced by such an event, and also by the following re-stratification. The deep convection event (0-1500 m) that occurred in winter 2010-2011 in the NW Mediterranean Sea resulted in a homogenization of the prokaryotic communities over the entire convective cell, resulting in the predominance of typical surface Bacteria, such as Oceanospirillale and Flavobacteriales. Statistical analysis together with numerical simulation of vertical homogenization evidenced that physical turbulence only was not enough to explain the new distribution of the communities, but acted in synergy with other parameters such as exported particulate and dissolved organic matters. The convection also stimulated prokaryotic abundance (+21%) and heterotrophic production (+43%) over the 0-1500 m convective cell, and resulted in a decline of cell-specific extracellular enzymatic activities (-67%), thus suggesting an intensification of the labile organic matter turnover during the event. The rapid re-stratification of the prokaryotic diversity and activities in the intermediate layer 5 days after the intense mixing indicated a marked resilience of the communities, apart from the residual deep mixed water patch.

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

    PubMed

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

    2016-03-01

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

  8. Open water bells

    NASA Astrophysics Data System (ADS)

    Paramati, Manjula; Tirumkudulu, Mahesh S.

    2016-03-01

    A smooth circular moving liquid sheet is formed by the head-on impingement of two equal laminar water jets. We subject such a liquid sheet to uniform laminar air flow from one side such that the direction of air velocity is perpendicular to the liquid sheet. The pressure of the moving air deforms the liquid sheet giving rise to an open water bell. The water bell is symmetric suggesting that the gas flow around the bell is also symmetric and that the gravitational force is negligible. We have captured the shape of the water bells for varying air flow rates and for varying Weber numbers, and compared the measurements with theoretical predictions obtained from a force balance involving liquid inertia, surface tension, and pressure difference across the sheet. The pressure exerted by the gas phase on the front and the rear surface of the deformed liquid sheet is obtained from known results of flow past flat circular discs. The predicted steady state shapes match well with the measurements at low Weber numbers but differences are observed at high Weber numbers, where the sheet flaps and is no longer smooth. Interestingly, the shape predicted by assuming a constant pressure difference equal to the stagnation pressure over the whole of the front face of the sheet and free stream value over the whole of the rear face yields nearly identical results suggesting that an open water bell is similar to a closed water bell in that, to a good approximation, the pressure on either sides of the water bell is homogeneous.

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

    PubMed

    Bemal, Suchandan; Anil, Arga Chandrashekar

    2016-11-01

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

  10. Open ocean Internal Waves, Namibia Coast, Africa.

    NASA Technical Reports Server (NTRS)

    1990-01-01

    These open ocean Internal Waves were seen off the Namibia Coast, Africa (19.5S, 11.5E). The periodic and regularly spaced sets of incoming internal appear to be diffracting against the coastline and recombining to form a network of interference patterns. They seem to coincide with tidal periods about 12 hours apart and wave length (distance from crest to crest) varies between 1.5 and 5.0 miles and the crest lengths stretch beyond the image.

  11. Open ocean Internal Waves, Namibia Coast, Africa.

    NASA Technical Reports Server (NTRS)

    1990-01-01

    These open ocean Internal Waves were seen off the Namibia Coast, Africa (23.0S, 14.0E). The periodic and regularly spaced sets of internal waves most likely coincide with tidal periods about 12 hours apart. The wave length (distance from crest to crest) varies between 1.5 and 5.0 miles and the crest lengths stretch across and beyond the distance of the photo. The waves are intersecting the Namibia coastline at about a 30 degree angle.

  12. Open ocean Internal Waves, Namibia Coast, Africa.

    NASA Image and Video Library

    1990-12-10

    These open ocean Internal Waves were seen off the Namibia Coast, Africa (19.5S, 11.5E). The periodic and regularly spaced sets of incoming internal appear to be diffracting against the coastline and recombining to form a network of interference patterns. They seem to coincide with tidal periods about 12 hours apart and wave length (distance from crest to crest) varies between 1.5 and 5.0 miles and the crest lengths stretch beyond the image.

  13. Open ocean Internal Waves, Namibia Coast, Africa.

    NASA Image and Video Library

    1990-12-10

    These open ocean Internal Waves were seen off the Namibia Coast, Africa (23.0S, 14.0E). The periodic and regularly spaced sets of internal waves most likely coincide with tidal periods about 12 hours apart. The wave length (distance from crest to crest) varies between 1.5 and 5.0 miles and the crest lengths stretch across and beyond the distance of the photo. The waves are intersecting the Namibia coastline at about a 30 degree angle.

  14. Degradation Signatures of Open Ocean Microplastic Debris

    NASA Astrophysics Data System (ADS)

    Lavender Law, K. L.; Donohue, J. L.; Collins, T.; Proskurowsi, G.; Andrady, A. L.

    2016-02-01

    Microplastics collected from the open ocean offer few clues about their origin and history. There is currently no method to determine how long ocean plastic has undergone environmental weathering, how quickly fragmentation has occurred, or how small microplastic particles will ultimately become before (or if) they are fully degraded by microbial action. In the current absence of results from laboratory and field experiments designed to address these questions, we meticulously examined physical and chemical characteristics of open ocean microplastic particles collected over a 16-year period for clues about their weathering history. More than 1000 microplastic particles collected in the western North Atlantic between 1991 and 2007 were analyzed to determine polymer type, material density, mass and particle size, and were used to create a detailed catalogue of common microscopic surface features likely related to environmental exposure and weathering. Polyethylene and polypropylene, the two buoyant resins most commonly collected at the sea surface, can typically be distinguished by visual microscopy alone, and their particular characteristics lead us to hypothesize that these two resins weaken and fragment in different ways and on different time scales. A subset of resin pellets collected at sea were also analyzed using FTIR-ATR and/or FTIR microscopy for signatures of chemical degradation (e.g., carbonyl index) that are related to physical weathering characteristics such as color, quantified by the yellowness index.

  15. Manifestation, Drivers, and Emergence of Open Ocean Deoxygenation.

    PubMed

    Levin, Lisa A

    2017-09-29

    Oxygen loss in the ocean, termed deoxygenation, is a major consequence of climate change and is exacerbated by other aspects of global change. An average global loss of 2% or more has been recorded in the open ocean over the past 50-100 years, but with greater oxygen declines in intermediate waters (100-600 m) of the North Pacific, the East Pacific, tropical waters, and the Southern Ocean. Although ocean warming contributions to oxygen declines through a reduction in oxygen solubility and stratification effects on ventilation are reasonably well understood, it has been a major challenge to identify drivers and modifying factors that explain different regional patterns, especially in the tropical oceans. Changes in respiration, circulation (including upwelling), nutrient inputs, and possibly methane release contribute to oxygen loss, often indirectly through stimulation of biological production and biological consumption. Microbes mediate many feedbacks in oxygen minimum zones that can either exacerbate or ameliorate deoxygenation via interacting nitrogen, sulfur, and carbon cycles. The paleo-record reflects drivers of and feedbacks to deoxygenation that have played out through the Phanerozoic on centennial, millennial, and hundred-million-year timescales. Natural oxygen variability has made it difficult to detect the emergence of a climate-forced signal of oxygen loss, but new modeling efforts now project emergence to occur in many areas in 15-25 years. Continued global deoxygenation is projected for the next 100 or more years under most emissions scenarios, but with regional heterogeneity. Notably, even small changes in oxygenation can have significant biological effects. New efforts to systematically observe oxygen changes throughout the open ocean are needed to help address gaps in understanding of ocean deoxygenation patterns and drivers. Expected final online publication date for the Annual Review of Marine Science Volume 10 is January 3, 2018. Please see http

  16. Open Ocean Internal Waves, South China Sea

    NASA Technical Reports Server (NTRS)

    1989-01-01

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

  17. Clouds and Open Ocean near the Bahamas

    NASA Image and Video Library

    1982-07-04

    STS004-41-1206 (27 June-4July 1982) --- Sunglint reflects off the water of the North Atlantic Ocean in an area to the east of the Bahamas Islands sometimes called the Sargasso Sea. The area has also been referred to as the ?Bermuda Triangle.? Astronauts Thomas K. Mattingly II, STS-4 commander, and Henry W. Hartsfield Jr., pilot, spent seven days and one hour aboard the Earth-orbiting space shuttle Columbia and performed a variety of duties in addition to those of recording 70mm and 35mm imagery. Photo credit: NASA

  18. Species composition, timing, and weather correlates of autumn open-water crossings by raptors migrating along the East-Asian Oceanic Flyway

    USGS Publications Warehouse

    Concepcion, Camille B.; Dumandan, Patricia T.; Silvosa, Medel R.; Bildstein, Keith L.; Katzner, Todd E.

    2017-01-01

    Raptor migration rarely involves long-distance movements across open oceans. One exception occurs along the East-Asian Oceanic Flyway. We collected migration data at two terrestrial hawkwatch sites along this flyway to better understand open-ocean movements along this largely overwater corridor. At the northern end of the Philippines, at Basco on the island of Batan, we recorded 7587 migratory raptors in autumn 2014. Near the southern end of the Philippines, at Cape San Agustin on the island of Mindanao, we recorded 27,399 raptors migrating in autumn 2012. Chinese Sparrowhawks (Accipiter soloensis) were the most common raptors observed, making up approximately 89% and 92% of total records for Basco and Cape San Agustin, respectively. The Grey-faced Buzzard (Butastur indicus) was the second most common raptor migrant, accounting for 8% of the total counts at both watch sites. The migration period was about 1–2 wk earlier at Basco, the more northerly site, than at Cape San Agustin. Overwater flights at Basco peaked in both the morning and late afternoon, whereas at Cape San Agustin there was only a morning peak. In general, the rate of migration passage at both sites was highest with clear skies when winds were blowing from the northwest. However, we observed interspecific differences in migration behavior at both sites, with Accipiters more likely to be observed with tailwinds and eastward winds, and Grey-faced Buzzards more likely observed with headwinds. These results help to characterize poorly known aspects of raptor biology and to identify potential migratory bottlenecks or key sites for raptor conservation in little-studied Philippine tropical ecosystems.

  19. Observations of open-ocean deep convection in the northwestern Mediterranean Sea: Seasonal and interannual variability of mixing and deep water masses for the 2007-2013 Period

    NASA Astrophysics Data System (ADS)

    Houpert, L.; Durrieu de Madron, X.; Testor, P.; Bosse, A.; D'Ortenzio, F.; Bouin, M. N.; Dausse, D.; Le Goff, H.; Kunesch, S.; Labaste, M.; Coppola, L.; Mortier, L.; Raimbault, P.

    2016-11-01

    We present here a unique oceanographic and meteorological data set focus on the deep convection processes. Our results are essentially based on in situ data (mooring, research vessel, glider, and profiling float) collected from a multiplatform and integrated monitoring system (MOOSE: Mediterranean Ocean Observing System on Environment), which monitored continuously the northwestern Mediterranean Sea since 2007, and in particular high-frequency potential temperature, salinity, and current measurements from the mooring LION located within the convection region. From 2009 to 2013, the mixed layer depth reaches the seabed, at a depth of 2330m, in February. Then, the violent vertical mixing of the whole water column lasts between 9 and 12 days setting up the characteristics of the newly formed deep water. Each deep convection winter formed a new warmer and saltier "vintage" of deep water. These sudden inputs of salt and heat in the deep ocean are responsible for trends in salinity (3.3 ± 0.2 × 10-3/yr) and potential temperature (3.2 ± 0.5 × 10-3 C/yr) observed from 2009 to 2013 for the 600-2300 m layer. For the first time, the overlapping of the three "phases" of deep convection can be observed, with secondary vertical mixing events (2-4 days) after the beginning of the restratification phase, and the restratification/spreading phase still active at the beginning of the following deep convection event.

  20. An original mode of symbiosis in open ocean plankton.

    PubMed

    Decelle, Johan; Probert, Ian; Bittner, Lucie; Desdevises, Yves; Colin, Sébastien; de Vargas, Colomban; Galí, Martí; Simó, Rafel; Not, Fabrice

    2012-10-30

    Symbiotic relationships are widespread in nature and are fundamental for ecosystem functioning and the evolution of biodiversity. In marine environments, photosymbiosis with microalgae is best known for sustaining benthic coral reef ecosystems. Despite the importance of oceanic microbiota in global ecology and biogeochemical cycles, symbioses are poorly characterized in open ocean plankton. Here, we describe a widespread symbiotic association between Acantharia biomineralizing microorganisms that are abundant grazers in plankton communities, and members of the haptophyte genus Phaeocystis that are cosmopolitan bloom-forming microalgae. Cophylogenetic analyses demonstrate that symbiont biogeography, rather than host taxonomy, is the main determinant of the association. Molecular dating places the origin of this photosymbiosis in the Jurassic (ca. 175 Mya), a period of accentuated marine oligotrophy. Measurements of intracellular dimethylated sulfur indicate that the host likely profits from antioxidant protection provided by the symbionts as an adaptation to life in transparent oligotrophic surface waters. In contrast to terrestrial and marine symbioses characterized to date, the symbiont reported in this association is extremely abundant and ecologically active in its free-living phase. In the vast and barren open ocean, partnership with photosymbionts that have extensive free-living populations is likely an advantageous strategy for hosts that rely on such interactions. Discovery of the Acantharia-Phaeocystis association contrasts with the widely held view that symbionts are specialized organisms that are rare and ecologically passive outside the host.

  1. An original mode of symbiosis in open ocean plankton

    PubMed Central

    Decelle, Johan; Probert, Ian; Bittner, Lucie; Desdevises, Yves; Colin, Sébastien; de Vargas, Colomban; Galí, Martí; Simó, Rafel; Not, Fabrice

    2012-01-01

    Symbiotic relationships are widespread in nature and are fundamental for ecosystem functioning and the evolution of biodiversity. In marine environments, photosymbiosis with microalgae is best known for sustaining benthic coral reef ecosystems. Despite the importance of oceanic microbiota in global ecology and biogeochemical cycles, symbioses are poorly characterized in open ocean plankton. Here, we describe a widespread symbiotic association between Acantharia biomineralizing microorganisms that are abundant grazers in plankton communities, and members of the haptophyte genus Phaeocystis that are cosmopolitan bloom-forming microalgae. Cophylogenetic analyses demonstrate that symbiont biogeography, rather than host taxonomy, is the main determinant of the association. Molecular dating places the origin of this photosymbiosis in the Jurassic (ca. 175 Mya), a period of accentuated marine oligotrophy. Measurements of intracellular dimethylated sulfur indicate that the host likely profits from antioxidant protection provided by the symbionts as an adaptation to life in transparent oligotrophic surface waters. In contrast to terrestrial and marine symbioses characterized to date, the symbiont reported in this association is extremely abundant and ecologically active in its free-living phase. In the vast and barren open ocean, partnership with photosymbionts that have extensive free-living populations is likely an advantageous strategy for hosts that rely on such interactions. Discovery of the Acantharia–Phaeocystis association contrasts with the widely held view that symbionts are specialized organisms that are rare and ecologically passive outside the host. PMID:23071304

  2. Seasonal changes in the distribution of dissolved organic nitrogen in coastal and open-ocean waters in the North East Pacific: sources and sinks

    NASA Astrophysics Data System (ADS)

    Wong, C. S.; Yu, Z.; Waser, N. A. D.; Whitney, F. A.; Johnson, W. K.

    The distribution of dissolved organic nitrogen (DON) and nitrate were determined seasonally (winter, spring and summer) during three years along line P, i.e. an E-W transect from the coast of British Columbia, Canada, to Station P (50°N, 145°W) in the subarctic North East Pacific Ocean. In conjunction, DON measurements were made in the Straits of Juan de Fuca and Georgia within an estuarine system connected to the NE Pacific Ocean. The distribution of DON at the surface showed higher values of 4-17 μM in the Straits relative to values of 4-10 μM encountered along line P, respectively. Along line P, the concentration of DON showed an inshore-offshore gradient at the surface with higher values near the coast. The equation for the conservation of DON showed that horizontal transport of DON (inshore-offshore) was much larger than vertical physical mixing. Horizontal advection of DON-rich waters from the coastal estuarine system to the NE Pacific Ocean was likely the cause of the inshore-offshore gradient in the concentration of DON. Although the concentration of DON was very variable in space and time, it increased from winter to summer, with an average build up of 4.3 μM in the Straits and 0.7 μM in the NE subarctic Pacific. This implied seasonal DON sources of 0.3 mmol N m -2 d -1 at Station P and 1.5 mmol N m -2 d -1 in the Straits, respectively. These seasonal DON accumulation rates corresponded to about 15-20% of the seasonal nitrate uptake and suggested that there was a small seasonal build up of labile DON at the surface. However, the long residence times of 180-1560 d indicated that the most of the DON pool in surface waters was refractory in two very different productivity regimes of the NE Pacific.

  3. The polarization of light in coastal and open oceans: Reflection and transmission by the air-sea interface and application for the retrieval of water optical properties

    NASA Astrophysics Data System (ADS)

    Foster, Robert

    For decades, traditional remote sensing retrieval methods that rely solely on the spectral intensity of the water-leaving light have provided indicators of aquatic ecosystem health. With the increasing demand for new water quality indicators and improved accuracy of existing ones, the limits of traditional remote sensing approaches are becoming apparent. Use of the additional information intrinsic to the polarization state of light is therefore receiving more attention. One of the major challenges inherent in any above-surface determination of the water-leaving radiance, scalar or vector, is the removal of extraneous light which has not interacted with the water body and is therefore not useful for remote sensing of the water itself. Due in-part to the lack of a proven alternative, existing polarimeter installations have thus far assumed that such light was reflected by a flat sea surface, which can lead to large inaccuracies in the water-leaving polarization signal. This dissertation rigorously determines the full Mueller matrices for both surface-reflected skylight and upwardly transmitted light by a wind-driven ocean surface. A Monte Carlo code models the surface in 3D and performs polarized ray-tracing, while a vector radiative transfer (VRT) simulation generates polarized light distributions from which the initial Stokes vector for each ray is inferred. Matrices are computed for the observable range of surface wind speeds, viewing and solar geometries, and atmospheric aerosol loads. Radiometer field-of-view effects are also assessed. Validation of the results is achieved using comprehensive VRT simulations of the atmosphere-ocean system based on several oceanographic research cruises and specially designed polarimeters developed by the City College of New York: one submerged beneath the surface and one mounted on a research vessel. When available, additional comparisons are made at 9 km altitude with the NASA Research Scanning Polarimeter (RSP). Excellent

  4. Southern Ocean bottom water characteristics in CMIP5 models

    NASA Astrophysics Data System (ADS)

    Heuzé, CéLine; Heywood, Karen J.; Stevens, David P.; Ridley, Jeff K.

    2013-04-01

    Southern Ocean deep water properties and formation processes in climate models are indicative of their capability to simulate future climate, heat and carbon uptake, and sea level rise. Southern Ocean temperature and density averaged over 1986-2005 from 15 CMIP5 (Coupled Model Intercomparison Project Phase 5) climate models are compared with an observed climatology, focusing on bottom water. Bottom properties are reasonably accurate for half the models. Ten models create dense water on the Antarctic shelf, but it mixes with lighter water and is not exported as bottom water as in reality. Instead, most models create deep water by open ocean deep convection, a process occurring rarely in reality. Models with extensive deep convection are those with strong seasonality in sea ice. Optimum bottom properties occur in models with deep convection in the Weddell and Ross Gyres. Bottom Water formation processes are poorly represented in ocean models and are a key challenge for improving climate predictions.

  5. Conversion of the CLUSE Model for Applications over Open Ocean: Progress Report

    DTIC Science & Technology

    1993-08-01

    and temperature profiles [Rouault et aL, 1991]. Extension to open ocean conditions requires that the fresh water droplets are replaced by sea-salt...applies to open ocean conditions. The calculation of the profiles of the mean wind velocity and turbulent diffusivity has been changed to take into account...the waves in a non-turbulent and non-evaporative atmosphere. This module yields vertical profiles of droplet concentrations that enter in the

  6. Comparison of the cloud activation potential of open ocean and coastal aerosol in the Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Vidaurre, G.; Brooks, S. D.; Thornton, D. C.

    2010-12-01

    Continuous measurements of aerosol concentration, particle size distribution, and cloud activation potential between 0.15 and 1.2% supersaturation were performed for open ocean and coastal air during the Halocarbon Air Sea Transect - Pacific (HalocAST) campaign. The nearly 7000 mile transect, aboard the R/V Thomas G. Thompson, started in Punta Arenas, Chile and ended in Seattle, Washington. Air mass source regions were identified on the basis of air mass back trajectories. For air masses in the southern hemisphere, aerosols sampled over the open ocean acted as cloud condensation nuclei at supersaturations between 0.5 and 1%, while coastal aerosols required higher supersaturations. In the pristine open ocean, observed aerosol concentrations were very low, typically below 200 cm-3, with an average particle diameter of approximately 0.4 μm. On the other hand, coastal aerosol concentrations were above 1000 cm-3 with an average particle diameter of 0.7 μm. Air masses originating in the northern hemisphere had much higher aerosol loads, between 500 and 2000 cm-3 over the ocean and above 4000 cm-3 at the coast. In both cases, the average particle diameters were approximately 0.5 μm. Measurements suggest that the northern hemisphere, substantially more polluted than the southern hemisphere, is characterized by alternating regions of high and medium aerosol number concentration. In addition, measurements of microorganism and organic matter concentration in the surface layer of the ocean water were conducted along the cruise track, to test the hypothesis that biogenic aerosol containing marine organic matter contribute to cloud activation potential. There was a significant correlation between mean aerosol diameter and prokaryote concentration in surface waters (r = 0.585, p < 0.01, n = 24), and between critical supersaturation and prokaryote concentration in surface waters (r = 0.538, p < 0.01, n = 24). This correlation indicates that larger aerosols occurred over water

  7. Implementing an Open Ocean Theater in NPSNET

    DTIC Science & Technology

    1994-03-01

    ocean surface is necessary to more accurately model both visual and radar detection of submarine periscopes. In a flat blue ocean simulation, visual...identification of small foreign objects, e.g. a periscope mast, is unnaturally simple. Similarly in a computer-modeled radar , the absence of sea clutter...caused by the reflection of radar waves off wave peaks will produce an artificially inflated accuracy of the detection and identification of periscope

  8. Increase in acidifying water in the western Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Qi, Di; Chen, Liqi; Chen, Baoshan; Gao, Zhongyong; Zhong, Wenli; Feely, Richard A.; Anderson, Leif G.; Sun, Heng; Chen, Jianfang; Chen, Min; Zhan, Liyang; Zhang, Yuanhui; Cai, Wei-Jun

    2017-02-01

    The uptake of anthropogenic CO2 by the ocean decreases seawater pH and carbonate mineral aragonite saturation state (Ωarag), a process known as Ocean Acidification (OA). This can be detrimental to marine organisms and ecosystems. The Arctic Ocean is particularly sensitive to climate change and aragonite is expected to become undersaturated (Ωarag < 1) there sooner than in other oceans. However, the extent and expansion rate of OA in this region are still unknown. Here we show that, between the 1990s and 2010, low Ωarag waters have expanded northwards at least 5°, to 85° N, and deepened 100 m, to 250 m depth. Data from trans-western Arctic Ocean cruises show that Ωarag < 1 water has increased in the upper 250 m from 5% to 31% of the total area north of 70° N. Tracer data and model simulations suggest that increased Pacific Winter Water transport, driven by an anomalous circulation pattern and sea-ice retreat, is primarily responsible for the expansion, although local carbon recycling and anthropogenic CO2 uptake have also contributed. These results indicate more rapid acidification is occurring in the Arctic Ocean than the Pacific and Atlantic oceans, with the western Arctic Ocean the first open-ocean region with large-scale expansion of `acidified’ water directly observed in the upper water column.

  9. Open cycle ocean thermal energy conversion system structure

    DOEpatents

    Wittig, J. Michael

    1980-01-01

    A generally mushroom-shaped, open cycle OTEC system and distilled water producer which has a skirt-conduit structure extending from the enlarged portion of the mushroom to the ocean. The enlarged part of the mushroom houses a toroidal casing flash evaporator which produces steam which expands through a vertical rotor turbine, partially situated in the center of the blossom portion and partially situated in the mushroom's stem portion. Upon expansion through the turbine, the motive steam enters a shell and tube condenser annularly disposed about the rotor axis and axially situated beneath the turbine in the stem portion. Relatively warm ocean water is circulated up through the radially outer skirt-conduit structure entering the evaporator through a radially outer portion thereof, flashing a portion thereof into motive steam, and draining the unflashed portion from the evaporator through a radially inner skirt-conduit structure. Relatively cold cooling water enters the annular condenser through the radially inner edge and travels radially outwardly into a channel situated along the radially outer edge of the condenser. The channel is also included in the radially inner skirt-conduit structure. The cooling water is segregated from the potable, motive steam condensate which can be used for human consumption or other processes requiring high purity water. The expansion energy of the motive steam is partially converted into rotational mechanical energy of the turbine rotor when the steam is expanded through the shaft attached blades. Such mechanical energy drives a generator also included in the enlarged mushroom portion for producing electrical energy. Such power generation equipment arrangement provides a compact power system from which additional benefits may be obtained by fabricating the enclosing equipment, housings and component casings from low density materials, such as prestressed concrete, to permit those casings and housings to also function as a floating

  10. Ocean-to-Ocean Dissimilarities of Salty Subtropical Surface Water

    NASA Astrophysics Data System (ADS)

    Gordon, A. L.

    2014-12-01

    Each ocean basin displays its own 'personality', reflecting its degree of isolation or connectivity to the global ocean, its place in the interocean exchange network and associated ocean overturning circulation systems, as well as regional circulation and air-sea exchange patterns. While dissimilarities are most notable in the northern hemisphere (the salty North Atlantic vs the fresher North Pacific; as well as the salty Arabian and the fresher Bay of Bengal, a miniature Atlantic/Pacific analog?) far removed from the grand equalizing interocean link of the circum-Antarctic belt, and where large continental blocks impose contrasting forcing, the southern hemisphere ocean basins also display differences. Ocean to ocean dissimilarities are evident in the dry subtropical climate belt, marked by deserts on land and salty surface ocean water. The subtropical sea surface salinity maximum (SSS-max) patterns of 5 the subtropical regimes (the North and South Atlantic, North and South Pacific, and the southern Indian Ocean) display significant dissimilarities in their relative position within their ocean basin, in the structure and seasonality of the SSS-max pattern. The near synoptic coverage of Aquarius and Argo profilers are further defining interannual variability. The South Atlantic SSS-max is pressed against the western boundary, whereas in the other regimes the SSS-max falls within the eastern half of the ocean basin, though the western South Pacific displays a secondary SSS-max. For further details see: A. Gordon, C. Giulivi, J. Busecke, F. Bingham, submitted to the SPURS Oceanography special issue.

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

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    2010-01-01

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

  13. Assessing Atmospheric Water Injection from Oceanic Impacts

    NASA Technical Reports Server (NTRS)

    Pierazzo, E.

    2005-01-01

    Collisions of asteroids and comets with the Earth s surface are rare events that punctuate the geologic record. Due to the vastness of Earth s oceans, oceanic impacts of asteroids or comets are expected to be about 4 times more frequent than land impacts. The resulting injections of oceanic water into the upper atmosphere can have important repercussions on Earth s climate and atmospheric circulation. However, the duration and overall effect of these large injections are still unconstrained. This work addresses atmospheric injections of large amounts of water in oceanic impacts.

  14. Large mesopelagic fishes biomass and trophic efficiency in the open ocean

    PubMed Central

    Irigoien, Xabier; Klevjer, T. A.; Røstad, A.; Martinez, U.; Boyra, G.; Acuña, J. L.; Bode, A.; Echevarria, F.; Gonzalez-Gordillo, J. I.; Hernandez-Leon, S.; Agusti, S.; Aksnes, D. L.; Duarte, C. M.; Kaartvedt, S.

    2014-01-01

    With a current estimate of ~1,000 million tons, mesopelagic fishes likely dominate the world total fishes biomass. However, recent acoustic observations show that mesopelagic fishes biomass could be significantly larger than the current estimate. Here we combine modelling and a sensitivity analysis of the acoustic observations from the Malaspina 2010 Circumnavigation Expedition to show that the previous estimate needs to be revised to at least one order of magnitude higher. We show that there is a close relationship between the open ocean fishes biomass and primary production, and that the energy transfer efficiency from phytoplankton to mesopelagic fishes in the open ocean is higher than what is typically assumed. Our results indicate that the role of mesopelagic fishes in oceanic ecosystems and global ocean biogeochemical cycles needs to be revised as they may be respiring ~10% of the primary production in deep waters. PMID:24509953

  15. Large mesopelagic fishes biomass and trophic efficiency in the open ocean.

    PubMed

    Irigoien, Xabier; Klevjer, T A; Røstad, A; Martinez, U; Boyra, G; Acuña, J L; Bode, A; Echevarria, F; Gonzalez-Gordillo, J I; Hernandez-Leon, S; Agusti, S; Aksnes, D L; Duarte, C M; Kaartvedt, S

    2014-01-01

    With a current estimate of ~1,000 million tons, mesopelagic fishes likely dominate the world total fishes biomass. However, recent acoustic observations show that mesopelagic fishes biomass could be significantly larger than the current estimate. Here we combine modelling and a sensitivity analysis of the acoustic observations from the Malaspina 2010 Circumnavigation Expedition to show that the previous estimate needs to be revised to at least one order of magnitude higher. We show that there is a close relationship between the open ocean fishes biomass and primary production, and that the energy transfer efficiency from phytoplankton to mesopelagic fishes in the open ocean is higher than what is typically assumed. Our results indicate that the role of mesopelagic fishes in oceanic ecosystems and global ocean biogeochemical cycles needs to be revised as they may be respiring ~10% of the primary production in deep waters.

  16. Modeling water clarity in oceans and coasts

    EPA Science Inventory

    In oceans and coastal waters, phytoplankton is the primary producer of organic compounds which form the base for the food chain. The concentration of phytoplankton is a major factor controlling water clarity and the depth to which light penetrates in the water column. The light i...

  17. Modeling water clarity in oceans and coasts

    EPA Science Inventory

    In oceans and coastal waters, phytoplankton is the primary producer of organic compounds which form the base for the food chain. The concentration of phytoplankton is a major factor controlling water clarity and the depth to which light penetrates in the water column. The light i...

  18. Open-cycle Ocean Thermal Energy Conversion (OTEC): Status and potential

    NASA Astrophysics Data System (ADS)

    Bharathan, D.

    1984-08-01

    Tropical oceans with a 20 C or more temperature difference between surface and deep water represent a vast resource of renewable thermal energy. One of the methods of harnessing this resource is an open-cycle Ocean Thermal Energy Conversion (OTEC) system utilizing steam evaporated from the surface water for powering the turbine. In this paper, the state of the art of research and component development, as related to heat and mass transfer processes, power production, noncondensable gas handling, and seawater flow hydraulics, are described through an illustrated preliminary design study of a 1-MW facility.

  19. A heterogeneous open ocean source for glyoxal and iodine oxide

    NASA Astrophysics Data System (ADS)

    Volkamer, R.; Coburn, S.; Dix, B. K.; Lechner, M.; Sinreich, R.; Duhl, T.; Guenther, A. B.

    2010-12-01

    The climate relevance of biologically active ocean upwelling regions has primarily been studied in terms of the air-sea partitioning of long-lived greenhouse gases (e.g., CO2, CH4, N2O etc), and the release of the reactive gas DMS, which can form aerosols as a result of atmospheric transformations. Considerably less attention has been paid to open ocean sources of other reactive gases that, like DMS, can form aerosols. Such molecules are glyoxal (CHOCHO) and IO. Glyoxal is an indicator for oxidative hydrocarbon chemistry, and a building block for secondary organic aerosol (SOA). SOA modifies the hygroscopic properties of organic aerosols, and potentially also adds to the growth of small particles to sizes that can more easily activate to form cloud droplets. Iodine oxide (IO) can nucleate new particles, and/or adds to the growth of pre-existing particles. Due to the very high solubility of the glyoxal molecule, concentrations in excess of 100ppt over the open ocean like we found over the Pacific Ocean require an airborne source mechanism (Sinreich et al., 2010). We have investigated the source mechanism further during a ship campaign in 2009, as well as a first research flight aboard the NSF/NCAR GV research aircraft (HIAPER). Both campaigns give clues about the sources of both gases over the remote tropical Pacific Ocean, and reveal a surprising impact on the composition of the free troposphere.

  20. Liquid Water Oceans in Ice Giants

    NASA Technical Reports Server (NTRS)

    Wiktorowicz, Sloane J.; Ingersoll, Andrew P.

    2007-01-01

    Aptly named, ice giants such as Uranus and Neptune contain significant amounts of water. While this water cannot be present near the cloud tops, it must be abundant in the deep interior. We investigate the likelihood of a liquid water ocean existing in the hydrogen-rich region between the cloud tops and deep interior. Starting from an assumed temperature at a given upper tropospheric pressure (the photosphere), we follow a moist adiabat downward. The mixing ratio of water to hydrogen in the gas phase is small in the photosphere and increases with depth. The mixing ratio in the condensed phase is near unity in the photosphere and decreases with depth; this gives two possible outcomes. If at some pressure level the mixing ratio of water in the gas phase is equal to that in the deep interior, then that level is the cloud base. The gas below the cloud base has constant mixing ratio. Alternately, if the mixing ratio of water in the condensed phase reaches that in the deep interior, then the surface of a liquid ocean will occur. Below this ocean surface, the mixing ratio of water will be constant. A cloud base occurs when the photospheric temperature is high. For a family of ice giants with different photospheric temperatures, the cooler ice giants will have warmer cloud bases. For an ice giant with a cool enough photospheric temperature, the cloud base will exist at the critical temperature. For still cooler ice giants, ocean surfaces will result. A high mixing ratio of water in the deep interior favors a liquid ocean. We find that Neptune is both too warm (photospheric temperature too high) and too dry (mixing ratio of water in the deep interior too low) for liquid oceans to exist at present. To have a liquid ocean, Neptune s deep interior water to gas ratio would have to be higher than current models allow, and the density at 19 kbar would have to be approx. equal to 0.8 g/cu cm. Such a high density is inconsistent with gravitational data obtained during the Voyager

  1. Liquid Water Oceans in Ice Giants

    NASA Technical Reports Server (NTRS)

    Wiktorowicz, Sloane J.; Ingersoll, Andrew P.

    2007-01-01

    Aptly named, ice giants such as Uranus and Neptune contain significant amounts of water. While this water cannot be present near the cloud tops, it must be abundant in the deep interior. We investigate the likelihood of a liquid water ocean existing in the hydrogen-rich region between the cloud tops and deep interior. Starting from an assumed temperature at a given upper tropospheric pressure (the photosphere), we follow a moist adiabat downward. The mixing ratio of water to hydrogen in the gas phase is small in the photosphere and increases with depth. The mixing ratio in the condensed phase is near unity in the photosphere and decreases with depth; this gives two possible outcomes. If at some pressure level the mixing ratio of water in the gas phase is equal to that in the deep interior, then that level is the cloud base. The gas below the cloud base has constant mixing ratio. Alternately, if the mixing ratio of water in the condensed phase reaches that in the deep interior, then the surface of a liquid ocean will occur. Below this ocean surface, the mixing ratio of water will be constant. A cloud base occurs when the photospheric temperature is high. For a family of ice giants with different photospheric temperatures, the cooler ice giants will have warmer cloud bases. For an ice giant with a cool enough photospheric temperature, the cloud base will exist at the critical temperature. For still cooler ice giants, ocean surfaces will result. A high mixing ratio of water in the deep interior favors a liquid ocean. We find that Neptune is both too warm (photospheric temperature too high) and too dry (mixing ratio of water in the deep interior too low) for liquid oceans to exist at present. To have a liquid ocean, Neptune s deep interior water to gas ratio would have to be higher than current models allow, and the density at 19 kbar would have to be approx. equal to 0.8 g/cu cm. Such a high density is inconsistent with gravitational data obtained during the Voyager

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

    PubMed

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

    2010-10-10

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

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

    PubMed

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

    2015-08-01

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

  4. A review of ocean color remote sensing methods and statistical techniques for the detection, mapping and analysis of phytoplankton blooms in coastal and open oceans

    NASA Astrophysics Data System (ADS)

    Blondeau-Patissier, David; Gower, James F. R.; Dekker, Arnold G.; Phinn, Stuart R.; Brando, Vittorio E.

    2014-04-01

    The need for more effective environmental monitoring of the open and coastal ocean has recently led to notable advances in satellite ocean color technology and algorithm research. Satellite ocean color sensors' data are widely used for the detection, mapping and monitoring of phytoplankton blooms because earth observation provides a synoptic view of the ocean, both spatially and temporally. Algal blooms are indicators of marine ecosystem health; thus, their monitoring is a key component of effective management of coastal and oceanic resources. Since the late 1970s, a wide variety of operational ocean color satellite sensors and algorithms have been developed. The comprehensive review presented in this article captures the details of the progress and discusses the advantages and limitations of the algorithms used with the multi-spectral ocean color sensors CZCS, SeaWiFS, MODIS and MERIS. Present challenges include overcoming the severe limitation of these algorithms in coastal waters and refining detection limits in various oceanic and coastal environments. To understand the spatio-temporal patterns of algal blooms and their triggering factors, it is essential to consider the possible effects of environmental parameters, such as water temperature, turbidity, solar radiation and bathymetry. Hence, this review will also discuss the use of statistical techniques and additional datasets derived from ecosystem models or other satellite sensors to characterize further the factors triggering or limiting the development of algal blooms in coastal and open ocean waters.

  5. Impacts of atmospheric anthropogenic nitrogen on the open ocean.

    PubMed

    Duce, R A; LaRoche, J; Altieri, K; Arrigo, K R; Baker, A R; Capone, D G; Cornell, S; Dentener, F; Galloway, J; Ganeshram, R S; Geider, R J; Jickells, T; Kuypers, M M; Langlois, R; Liss, P S; Liu, S M; Middelburg, J J; Moore, C M; Nickovic, S; Oschlies, A; Pedersen, T; Prospero, J; Schlitzer, R; Seitzinger, S; Sorensen, L L; Uematsu, M; Ulloa, O; Voss, M; Ward, B; Zamora, L

    2008-05-16

    Increasing quantities of atmospheric anthropogenic fixed nitrogen entering the open ocean could account for up to about a third of the ocean's external (nonrecycled) nitrogen supply and up to approximately 3% of the annual new marine biological production, approximately 0.3 petagram of carbon per year. This input could account for the production of up to approximately 1.6 teragrams of nitrous oxide (N2O) per year. Although approximately 10% of the ocean's drawdown of atmospheric anthropogenic carbon dioxide may result from this atmospheric nitrogen fertilization, leading to a decrease in radiative forcing, up to about two-thirds of this amount may be offset by the increase in N2O emissions. The effects of increasing atmospheric nitrogen deposition are expected to continue to grow in the future.

  6. Is Europa's Subsurface Water Ocean Warm?

    NASA Technical Reports Server (NTRS)

    Melosh, H. J.; Ekholm, A. G.; Showman, A. P.; Lorenz, R. D.

    2002-01-01

    Europa's subsurface water ocean may be warm: that is, at the temperature of water's maximum density. This provides a natural explanation of chaos melt-through events and leads to a correct estimate of the age of its surface. Additional information is contained in the original extended abstract.

  7. Humboldt Open Ocean Disposal Site (HOODS) Survey Work 2014

    EPA Pesticide Factsheets

    The Humboldt Open Ocean Disposal Site (HOODS) is a dredged material disposal site located 3 nautical miles (nm) offshore of Humboldt Bay in Northern California. HOODS was permanently designated by EPA Region 9 in 1995, and has been actively used for dredged material disposal operations since then. The HOODS has received higher volumes of dredged material than predicted since its designation in 1995, mainly from USACE construction and maintenance dredging.

  8. Mapping the future expansion of Arctic open water

    NASA Astrophysics Data System (ADS)

    Barnhart, Katherine R.; Miller, Christopher R.; Overeem, Irina; Kay, Jennifer E.

    2016-03-01

    Sea ice impacts most of the Arctic environment, from ocean circulation and marine ecosystems to animal migration and marine transportation. Sea ice has thinned and decreased in age over the observational record. Ice extent has decreased. Reduced ice cover has warmed the surface ocean, accelerated coastal erosion and impacted biological productivity. Declines in Arctic sea-ice extent cannot be explained by internal climate variability alone and can be attributed to anthropogenic effects. However, extent is a poor measure of ice decline at specific locations as it integrates over the entire Arctic basin and thus contains no spatial information. The open water season, in contrast, is a metric that represents the duration of open water over a year at an individual location. Here we present maps of the open water season over the period 1920-2100 using daily output from a 30-member initial-condition ensemble of business-as-usual climate simulations that characterize the expansion of Arctic open water, determine when the open water season will move away from pre-industrial conditions (`shift’ time) and identify when human forcing will take the Arctic sea-ice system outside its normal bounds (`emergence’ time). The majority of the Arctic nearshore regions began shifting in 1990 and will begin leaving the range of internal variability in 2040. Models suggest that ice will cover coastal regions for only half of the year by 2070.

  9. The shape of extreme waves on the open ocean

    NASA Astrophysics Data System (ADS)

    Adcock, Thomas A. A.; Taylor, Paul H.; Draper, Scott

    2016-04-01

    This study investigates how non-linear physics modifies the largest waves in random seas relative to linear evolution. Our method follows that described in [1]. We start with random simulations of extreme waves in linear sea-states with realistic spectra and directional spreading. Each wave-group, with the surrounding waves, is propagated backwards in time under linear evolution for ten periods. This is then used as initial conditions for non-linear simulations. We compare the maximum of the wave-group in the non-linear simulation with that in the linear case. We do this multiple times for different randomly generated extreme events. We find that, on average, there is relatively little extra elevation in the non-linear case - although in a few cases there is significant amplification. However, there are significant changes to the average shape of the group. For moderate wave steepness there is an expansion of the wave-group in the lateral direction forming a broader crest than predicted by linear evolution. For the most severe sea-states there is a significant contraction of the wave-group in the mean wave direction. There is also a movement of the largest wave to the front of the wave-group, suggesting that the largest waves will be preceded by relatively small waves. Reference [1] ADCOCK, T.A.A., TAYLOR, P.H. & DRAPER, S. (2015) Non-linear dynamics of wave-groups in random seas: Unexpected walls of water in the open ocean, Proceedings of the Royal Society A 471(2184).

  10. Ocean Surface Water Sampling Devices.

    DTIC Science & Technology

    1963-10-01

    also parachuted, captures a volume of the water surface by a cookie cutter action and drew it into a 1-liter Thermos bottle for protection from...effective in landing upright on the water. Faster Dewar samplers without the cookie cutter action but with the same intake method proved about 95

  11. Bipolar Atlantic deepwater circulation in the middle-late Eocene: Effects of Southern Ocean gateway openings

    NASA Astrophysics Data System (ADS)

    Borrelli, Chiara; Cramer, Benjamin S.; Katz, Miriam E.

    2014-04-01

    We present evidence for Antarctic Circumpolar Current (ACC)-like effects on Atlantic deepwater circulation beginning in the late-middle Eocene. Modern ocean circulation is characterized by a thermal differentiation between Southern Ocean and North Atlantic deepwater formation regions. In order to better constrain the timing and nature of the initial thermal differentiation between Northern Component Water (NCW) and Southern Component Water (SCW), we analyze benthic foraminiferal stable isotope (δ18Obf and δ13Cbf) records from Ocean Drilling Program Site 1053 (upper deep water, western North Atlantic). Our data, compared with published records and interpreted in the context of ocean circulation models, indicate that progressive opening of Southern Ocean gateways and initiation of a circum-Antarctic current caused a transition to a modern-like deep ocean circulation characterized by thermal differentiation between SCW and NCW beginning ~38.5 Ma, in the initial stages of Drake Passage opening. In addition, the relatively low δ18Obf values recorded at Site 1053 show that the cooling trend of the middle-late Eocene was not global, because it was not recorded in the North Atlantic. The timing of thermal differentiation shows that NCW contributed to ocean circulation by the late-middle Eocene, ~1-4 Myr earlier than previously thought. We propose that early NCW originated in the Labrador Sea, based on tectonic reconstructions and changes in foraminiferal assemblages in this basin. Finally, we link further development of meridional isotopic gradients in the Atlantic and Pacific in the late Eocene with the Tasman Gateway deepening (~34 Ma) and the consequent development of a circumpolar proto-ACC.

  12. Southern Ocean ventilation and bottom water formation driven by Weddell Sea polynyas

    NASA Astrophysics Data System (ADS)

    Rheinlaender, Jonathan; Nisancioglu, Kerim; Smedsrud, Lars Henrik

    2017-04-01

    A distinct feature of the last glacial period, are the abrupt temperature fluctuations in Greenland associated with Dansgaard-Oeschger events and a similar but opposite response in Antarctica. The prevailing hypothesis behind this inter-hemispheric coupling, points to changes in deep water formation as the main driver, thus highlighting the pivotal role of the high latitude oceans in global climate. Bottom water formation through open-ocean deep convection in an Antarctic polynya, a large open water area inside the winter sea ice cover, provide a potential mechanism to trigger such changes in ocean circulation. In this study, an ocean-sea ice only version of the Norwegian Earth System Model (NorESM) is explored and shows strong open-ocean deep convection associated with large polynyas in the Weddell Sea. This provides us with an opportunity to test (1) how internal ocean dynamics can trigger abrupt changes in sea-ice cover and (2) how these polynyas affect the overturning circulation through changes in bottom water formation. During the 1,000 year long free-running simulation two polynyas are observed. We show, that the polynya is caused by subsurface warming leading to a gradual weakening of the surface stratification which destabilizes the whole water column and eventually triggers deep convective overturning. This mixes up relatively warm deep water causing extensive melt of sea ice in the Weddell Sea, while cold and fresh surface water sinks to the bottom. Consequently, the polynya leads to extensive bottom water formation and increase in the northward flow of Antarctic Bottom Water, while the southward flow of North Atlantic Deep Water is reduced. Finally, our results suggest that a decrease in the temperature of warm deep water in the Weddell Sea leads to cessation of open-ocean deep convection. This raises the question if open-ocean deep convection associated with polynyas in the Southern Ocean could be a realistic feature in a cold, glacial climate.

  13. Initial opening of the Eurasian Basin, Arctic Ocean

    NASA Astrophysics Data System (ADS)

    Berglar, Kai; Franke, Dieter; Lutz, Rüdiger; Schreckenberger, Bernd; Damm, Volkmar

    2016-10-01

    Analysis of the transition from the NE Yermak Plateau into the oceanic Eurasian Basin sheds light on the Paleocene formation of this Arctic basin. Newly acquired multichannel seismic data with a 3600 m long streamer shot during ice-free conditions enables the interpretation of crustal structures. Evidence is provided that no major compressional deformation affected the NE Yermak Plateau. The seismic data reveal that the margin is around 80 km wide and consists of rotated fault blocks, major listric normal faults, and half-grabens filled with syn-rift sediments. Taking into account published magnetic and gravimetric data, this setting is interpreted as a rifted continental margin, implying that the NE Yermak Plateau is of continental origin. The transition from the Yermak Plateau to the oceanic Eurasian Basin might be located at a prominent basement high, probably formed by exhumed mantle. In contrast to the Yermak Plateau margin, the North Barents Sea continental margin shows a steep continental slope with a relatively abrupt transition to the oceanic domain. Based on one composite seismic line, it is speculated that the initial opening direction of the Eurasian Basin in the Arctic Ocean was highly oblique to the present day seafloor spreading direction.

  14. Perfluorinated acids as novel chemical tracers of global circulation of ocean waters.

    PubMed

    Yamashita, Nobuyoshi; Taniyasu, Sachi; Petrick, Gert; Wei, Si; Gamo, Toshitaka; Lam, Paul K S; Kannan, Kurunthachalam

    2008-01-01

    Perfluorinated acids (PFAs) such as perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are global environmental contaminants. The physicochemical properties of PFAs are unique in that they have high water solubilities despite the low reactivity of carbon-fluorine bond, which also imparts high stability in the environment. Because of the high water solubilities, the open-ocean water column is suggested to be the final sink for PFOS and PFOA. However, little is known on the distribution of PFAs in the oceans around the world. Here we describe the horizontal (spatial) and vertical distribution of PFAs in ocean waters worldwide. PFOS and PFOA concentrations in the North Atlantic Ocean ranged from 8.6 to 36pg l(-1) and from 52 to 338pg l(-1), respectively, whereas the corresponding concentrations in the Mid Atlantic Ocean were 13-73pg l(-1) and 67-439pg l(-1). These were completely different from the surface waters of the South Pacific Ocean and the Indian Ocean (overall range of <5-11pg l(-1) for PFOS and PFOA). Vertical profiles of PFAs in the marine water column were associated with the global ocean circulation theory. Vertical profiles of PFAs in water columns from the Labrador Sea reflected the influx of the North Atlantic Current in surface waters, the Labrador Current in subsurface waters, and the Denmark Strait Overflow Water in deep layers below 2000m. Striking differences in the vertical and spatial distribution of PFAs, depending on the oceans, suggest that these persistent acids can serve as useful chemical tracers to allow us to study oceanic transportation by major water currents. The results provide evidence that PFA concentrations and profiles in the oceans adhere to a pattern consistent with the global "Broecker's Conveyor Belt" theory of open ocean water circulation.

  15. The impact of atmospheric aerosols on trace metal chemistry in open ocean surface seawater: 2. Copper

    NASA Astrophysics Data System (ADS)

    Maring, H. B.; Duce, R. A.

    1989-01-01

    Atmospheric deposition contributes copper to the surface ocean. The biogeochemical importance and fate of this copper is poorly understood for open ocean regions. Atmospheric aerosols collected at Enewetak Atoll, in the tropical North Pacific, were exposed to seawater and artificial rainwater in laboratory experiments. Aerosol copper during the high-dust season at Enewetak Atoll is made up of aluminosilicate, oceanic, and possibly soil organic matter components. During the low-dust season, aerosol copper appears to be essentially all of oceanic origin. Virtually all nonaluminosilicate copper in marine aerosols collected at Enewetak is soluble in seawater. Dissolved organic matter and possibly cations in seawater increase the dissolution of aerosol copper. The net atmospheric flux of soluble copper to the tropical North Pacific near Enewetak is approximately 0.13 nmol cm-2 yr-1 out of a total net atmospheric copper flux of 0.14 nmol cm-2 yr-1. Atmospheric deposition supplies roughly the same quantity of soluble copper to tropical open North Pacific surface waters as does upwelling to eastern North Pacific surface waters. Atmospheric copper deposition, which appears to be primarily of natural origin, may be the most important input of copper to the surface waters of the central gyre of the North Pacific.

  16. Photochemical degradation of Corexit components in ocean water.

    PubMed

    Glover, Caitlin M; Mezyk, Stephen P; Linden, Karl G; Rosario-Ortiz, Fernando L

    2014-09-01

    Due to the large quantities of dispersants used during the Deepwater Horizon spill in 2010, there were immediate concerns with regards to the fate and transport of the mixture in ocean waters. Direct and sensitized photolysis experiments were carried out for two compounds chosen as surrogates for the Corexit mixture (9500 and 9527) that were applied to surface waters during the oil spill in the Gulf of Mexico. The results showed that direct photolysis did not contribute significantly to the overall degradation (max ∼30%), therefore the focus shifted to sensitized photolysis, specifically the degradation stemming from the reaction rate with hydroxyl radical (HO). The direct photochemical degradation rates for two of the compounds, dioctyl sulfosuccinate (DOSS) and dipropylene glycol butyl ether (DGBE) were measured as 4.29×10(-6)s(-1) and 5.95×10(-6)s(-1), respectively; whereas the overall degradation rate in ocean water was 1.56×10(-5)s(-1) and 2.23×10(-5)s(-1). The formation rates and apparent quantum yields for HO formation were determined for six ocean water samples. The values ranged from 1.81×10(-5) near shore to 0.061×10(-5) for the open ocean. These degradation rates suggest the possibility for photolysis to play a role in the overall fate of Corexit.

  17. Carbon Sequestration through Sustainably Sourced Algal Fertilizer: Deep Ocean Water.

    NASA Astrophysics Data System (ADS)

    Sherman, M. T.

    2014-12-01

    Drawing down carbon from the atmosphere happens in the oceans when marine plants are growing due to the use of carbon dioxide for biological processes and by raising the pH of the water. Macro- and microscopic marine photosynthesizers are limited in their growth by the availability of light and nutrients (nitrogen, phosphorous, iron, etc.) Deep ocean water (DOW), oceanic water from bellow about 1000m, is a natural medium for marine algae, which contains all (except in rare circumstances) necessary components for algal growth and represents over 90% of the volume of the ocean. The introduction of DOW to a tropical or summer sea can increase chlorophyll from near zero to 60 mg per M3 or more. The form of the utilization infrastructure for DOW can roughly be divided into two effective types; the unconstrained release and the open pond system. Unconstrained release has the advantage of having relatively low infrastructure investment and is available to any area of the ocean. The open pond system has high infrastructure costs but enables intensive use of DOW for harvesting macro- and microalgae and sustainable mariculture. It also enables greater concomitant production of DOW's other potential products such as electricity or potable water. However, unlike an unconstrained release the open pond system can capture much of the biomaterial from the water and limits the impact to the surrounding ecosystem. The Tidal Irrigation and Electrical System (TIESystem), is an open pond that is to be constructed on a continental shelf. It harnesses the tidal flux to pump DOW into the pond on the rising tide and then uses the falling tide to pump biologically rich material out of the pond. This biomaterial represents fixed CO2 and can be used for biofuel or fertilizers. The TIESystem benefits from an economy of scale that increases at a rate that is roughly equal to the relationship of the circumference of a circle (the barrier that creates the open pond) to the area of the pond

  18. Light scattering by microorganisms in the open ocean

    NASA Astrophysics Data System (ADS)

    Stramski, Dariusz; Kiefer, Dale A.

    Recent enumeration and identification of marine particles that are less than 2μm in diameter, suggests that they may be the major source of light scattering in the open ocean. The living components of these small particles include viruses, heterotrophic and photoautotrophic bacteria and the smallest eucaryotic cells. In order to examine the relative contribution by these (and other) microorganisms to scattering, we have calculated a budget for both the total scattering and backscattering coefficients (at 550nm) of suspended particles. This budget is determined by calculating the product of the numerical concentration of particles of a given category and the scattering cross-section of that category. Values for this product are then compared to values for the particulate scattering coefficients predicted by the models of GORDON and MOREL (1983) and MOREL (1988). In order to make such a comparison, we have estimated both the total scattering and backscattering cross-section of various microbial components that include viruses, heterotrophic bacteria, prochlorophytes, cyanobacteria, ultrananoplankton (2-8μm), larger nanoplankton (8-20μm) and microplankton (>20 μm). Such determinations are based upon Mie scattering calculations and measurements of the cell size distribution and the absorption and scattering coefficients of microbial cultures. In addition, we have gathered published information on the numerical concentration of living and detrial marine particles in the size range from 0.03 to 100μm. The results of such a study are summarized as follows. The size distribution of microorganisms in the ocean roughly obeys an inverse 4th power law over three orders of magnitude in cell diameter, from 0.2 to 100μm. Thus, the size distribution of living organisms is similar to that for total particulate matter as determined by electronic particle counters. For representative values of refractive index, it appears that most of the scattering in the sea comes from

  19. The Early Opening of the Indian Ocean: An African Perspective

    NASA Astrophysics Data System (ADS)

    Gaina, C.; Labails, C.; Reeves, C.

    2010-12-01

    The timing and causes that led to Gondwana break-up remain controversial to date. An earlier opening of the Central Atlantic (Late Sinemurian, ca. 190 Ma) has been recently suggested, and new published models of the East Gondwana evolution allow for a breakup timing closer to Karoo volcanism (ca. 180 Ma). In this contribution we revise the early evolution of the Indian Ocean with an emphasis on the opening of the West Somali basin. It is generally accepted that the continental breakup of Gondwana in the East African region began with the onset of the southward drift of Madagascar (then connected with Antarctica and India) along the Davie Fracture Zone probably during the Early-Mid Jurassic. This motion led to the opening of the western Somali Basin. Although published kinematic models are able to explain and date some of the broad scale features of the Somali and Mozambique oceanic basins, the exact timing of rifting, the early stages of seafloor spreading and the timing of seafloor cessation in the western Somali Basin remain debatable. Our new study aims to investigate the relationship between the long history of rifting along the East African margins and the breakup structures by constructing a consistent database of structural elements and information about their evolution from updated published literature. A thorough investigation of the potential field data (magnetic and gravity anomalies) and an analysis of multichannel seismic reflection helped to identify deep crustal structure and continent-ocean transition zone in the study area. Magnetic anomaly data is re-analyzed and compared with published results in adjacent basins. The evolution of the East African margin (along Somali and Mozambique basins) is shown in a regional framework where consequences of an independent motion of the Madagascar plate are discussed. In addition, the timing of an Early Jurassic breakup of East Gondwana and possible mechanisms are presented within a regional geological context.

  20. Mercury concentration and speciation in the coastal and open ocean boundary layer

    NASA Astrophysics Data System (ADS)

    Laurier, Fabien; Mason, Robert

    2007-03-01

    Atmospheric elemental mercury and reactive gaseous mercury (RGHg) concentrations, as well as ancillary parameters and meteorological data, were collected during a cruise in the North Atlantic Ocean between Bermuda and Barbados and at two land-based sites: the Chesapeake Biological Laboratory (CBL), a semirural, coastal site, and a site within the city of Baltimore, Maryland. There were two deployments at CBL, including a 6-month deployment in 2003/2004. Wet deposition samples were collected and analyzed for mercury where possible. A diurnal change in RGHg concentration was found at both CBL and over the North Atlantic Ocean, with maxima in the afternoon that coincided with maximum UV radiation, demonstrating the importance of in situ formation of RGHg. The maxima in RGHg concentration did not coincide with elevated Hg0 but were often found under conditions of low wind speed, and over the ocean, under low ozone conditions. In contrast, at the urban site there was more evidence of local sources. The data collected at the sites are contrasted and compared and used to examine the factors controlling the formation of RGHg in open ocean and nearshore locales and to estimate the importance of the dry deposition of RGHg to surface waters. Finally, the data collected at CBL in 2002-2004 were compared to earlier data collected in 1997-2000 to examine trends in concentration with time and to contrast these with the open ocean data sets to examine changes in Hg0 at the hemispheric scale.

  1. An alternative early opening scenario for the Central Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Labails, Cinthia; Olivet, Jean-Louis; Aslanian, Daniel; Roest, Walter R.

    2010-09-01

    The opening of the Central Atlantic Ocean basin that separated North America from northwest Africa is well documented and assumed to have started during the Late Jurassic. However, the early evolution and the initial breakup history of Pangaea are still debated: most of the existing models are based on one or multiple ridge jumps at the Middle Jurassic leaving the oldest crust on the American side, between the East Coast Magnetic Anomaly (ECMA) and the Blake Spur Magnetic Anomaly (BSMA). According to these hypotheses, the BSMA represents the limit of the initial basin and the footprint subsequent to the ridge jump. Consequently, the evolution of the northwest African margin is widely different from the northeast American margin. However, this setting is in contradiction with the existing observations. In this paper, we propose an alternative scenario for the continental breakup and the Mesozoic spreading history of the Central Atlantic Ocean. The new model is based on an analysis of geophysical data (including new seismic lines, an interpretation of the newly compiled magnetic data, and satellite derived gravimetry) and recently published results which demonstrate that the opening of the Central Atlantic Ocean started already during the Late Sinemurian (190 Ma), based on a new identification of the African conjugate to the ECMA and on the extent of salt provinces off Morocco and Nova Scotia. The identification of an African conjugate magnetic anomaly to BSMA, the African Blake Spur Magnetic Anomaly (ABSMA), together with the significant change in basement topography, are in good agreement with that initial reconstruction. The early opening history for the Central Atlantic Ocean is described in four distinct phases. During the first 20 Myr after the initial breakup (190-170 Ma, from Late Sinemurian to early Bajocian), oceanic accretion was extremely slow (˜ 0.8 cm/y). At the time of Blake Spur (170 Ma, early Bajocian), a drastic change occurred both in the relative

  2. The Growing Human Footprint on Coastal and Open-Ocean Biogeochemistry

    NASA Astrophysics Data System (ADS)

    Doney, Scott C.

    2010-06-01

    Climate change, rising atmospheric carbon dioxide, excess nutrient inputs, and pollution in its many forms are fundamentally altering the chemistry of the ocean, often on a global scale and, in some cases, at rates greatly exceeding those in the historical and recent geological record. Major observed trends include a shift in the acid-base chemistry of seawater, reduced subsurface oxygen both in near-shore coastal water and in the open ocean, rising coastal nitrogen levels, and widespread increase in mercury and persistent organic pollutants. Most of these perturbations, tied either directly or indirectly to human fossil fuel combustion, fertilizer use, and industrial activity, are projected to grow in coming decades, resulting in increasing negative impacts on ocean biota and marine resources.

  3. The growing human footprint on coastal and open-ocean biogeochemistry.

    PubMed

    Doney, Scott C

    2010-06-18

    Climate change, rising atmospheric carbon dioxide, excess nutrient inputs, and pollution in its many forms are fundamentally altering the chemistry of the ocean, often on a global scale and, in some cases, at rates greatly exceeding those in the historical and recent geological record. Major observed trends include a shift in the acid-base chemistry of seawater, reduced subsurface oxygen both in near-shore coastal water and in the open ocean, rising coastal nitrogen levels, and widespread increase in mercury and persistent organic pollutants. Most of these perturbations, tied either directly or indirectly to human fossil fuel combustion, fertilizer use, and industrial activity, are projected to grow in coming decades, resulting in increasing negative impacts on ocean biota and marine resources.

  4. Extreme diversity in noncalcifying haptophytes explains a major pigment paradox in open oceans

    PubMed Central

    Liu, Hui; Probert, Ian; Uitz, Julia; Claustre, Hervé; Aris-Brosou, Stéphane; Frada, Miguel; Not, Fabrice; de Vargas, Colomban

    2009-01-01

    The current paradigm holds that cyanobacteria, which evolved oxygenic photosynthesis more than 2 billion years ago, are still the major light harvesters driving primary productivity in open oceans. Here we show that tiny unicellular eukaryotes belonging to the photosynthetic lineage of the Haptophyta are dramatically diverse and ecologically dominant in the planktonic photic realm. The use of Haptophyta-specific primers and PCR conditions adapted for GC-rich genomes circumvented biases inherent in classical genetic approaches to exploring environmental eukaryotic biodiversity and led to the discovery of hundreds of unique haptophyte taxa in 5 clone libraries from subpolar and subtropical oceanic waters. Phylogenetic analyses suggest that this diversity emerged in Paleozoic oceans, thrived and diversified in the permanently oxygenated Mesozoic Panthalassa, and currently comprises thousands of ribotypic species, belonging primarily to low-abundance and ancient lineages of the “rare biosphere.” This extreme biodiversity coincides with the pervasive presence in the photic zone of the world ocean of 19′-hexanoyloxyfucoxanthin (19-Hex), an accessory photosynthetic pigment found exclusively in chloroplasts of haptophyte origin. Our new estimates of depth-integrated relative abundance of 19-Hex indicate that haptophytes dominate the chlorophyll a-normalized phytoplankton standing stock in modern oceans. Their ecologic and evolutionary success, arguably based on mixotrophy, may have significantly impacted the oceanic carbon pump. These results add to the growing evidence that the evolution of complex microbial eukaryotic cells is a critical force in the functioning of the biosphere. PMID:19622724

  5. Annotated Bibliography of Water Optical Properties of Ocean Waters.

    DTIC Science & Technology

    1982-05-01

    in Optically Thick Media. Ocean and Applied Optics (15:12), 3266-3178, Dec. 24 I] Deep in a homogeneous medium that both scatters and absorbs photons...transmittance of the Rayleigh atmosphere are expressed as functions of optical thickness arid satellite measurement geometry with the aid of simple and...AD-A1iB 182 NAVAL OCEAN RES EARCH AND DEVELOPMENT ACTIVITY NSTL S--ETC F/i 8/10 ANNOTATED BIBLIOGRAPHY OF WATER OPTICAL PROPERTIES OF OCEAN WAT--ETC

  6. Coccolith Carbonate Burial in the Open Ocean: Neogene Patterns

    NASA Astrophysics Data System (ADS)

    Henderiks, J.

    2003-12-01

    Coccolithophorids, gold-brown algae, are prominent primary producers in the World's oceans. They produce calcite scales (coccoliths) that surround their cell, which represents a potential short-term CO2 source to the environment. The burial of coccoliths into marine sediments acts as a long-term sink of carbon. In fact, sedimentary carbonates are the largest reservoir of carbon on Earth, and hence play a vital role in the global carbon cycle. The contribution by coccolithophorids to this long-term sink can be expressed by accumulation rates of fine fraction carbonate. In more detail, absolute abundances of coccoliths combined with species-specific carbonate weights can resolve which taxa are most effective contributors to deep-sea carbonate. Surprisingly little has been done to link biogenic calcium carbonate budgets in the geological past to the general evolutionary patterns of calcifying plankton. Coccolithophorids have evolved relatively rapidly since their first appearance in the Mesozoic. Their evolutionary patterns are characterized by several periods of increasing species diversity and subsequent decline, as well as changes in their coccolith size and morphology. An overall decrease in the coccolith sizes is recorded during the Neogene, with the disappearance of large coccoliths (>10 micron) since the Middle Miocene. Because larger coccoliths are generally more resistant to dissolution, this observation cannot be due to (selective) carbonate dissolution. Hence, it implies significant variability in the amount of coccolith carbonate effectively buried through time, and potentially drastic changes in coccolithophorid productivity in the open ocean, with consequences for the short-term effects of biocalcification. This study focuses on Neogene proportions and accumulation rates of coccolith carbonate in selected well-preserved DSDP and ODP Sites from the Atlantic, Pacific and Indian Oceans, at a 1-2 M.y. resolution. Ultimately, the aim is to understand the

  7. Comparison of techniques for preserving dissolved nutrients in open-ocean seawater samples

    SciTech Connect

    Morse, J. W.; Hunt, M.; Zullig, J.; Mucci, A.; Mendez, T.

    1981-12-01

    A survey of recent literature on methods for preserving nutrients indicates that the major factors which have been considered are: filtration and type of filter, material and history of storage containers, the influence of light, storage temperature and how it is achieved, the effectiveness of various acids, poisons, and preservatives, and the source of the sample. No comprehensive studies of open ocean seawater were found. A comprehensive study of nutrient preservation techniques was conducted on surface and deep seawater samples collected in the Gulf Stream east of Miami, Florida. No preservation techniques were found to be satisfactory for near-surface open ocean seawater. Results for deep water samples are found to be substantially better. The degree of preservation was not substantially improved by complex techniques involving freezing and chemical additives. Storage of filtered samples in aged polyethylene bottles at 2/sup 0/C in the dark is recommended for samples that must be stored. (LEW)

  8. Marine mammal distribution in the open ocean: a comparison of ocean color data products and levant time scales

    NASA Astrophysics Data System (ADS)

    Ohern, J.

    2016-02-01

    Marine mammals are generally located in areas of enhanced surface primary productivity, though they may forage much deeper within the water column and higher on the food chain. Numerous studies over the past several decades have utilized ocean color data from remote sensing instruments (CZCS, MODIS, and others) to asses both the quantity and time scales over which surface primary productivity relates to marine mammal distribution. In areas of sustained upwelling, primary productivity may essentially grow in the secondary levels of productivity (the zooplankton and nektonic species on which marine mammals forage). However, in many open ocean habitats a simple trophic cascade does not explain relatively short time lags between enhanced surface productivity and marine mammal presence. Other dynamic features that entrain prey or attract marine mammals may be responsible for the correlations between marine mammals and ocean color. In order to investigate these features, two MODIS (moderate imaging spectroradiometer) data products, the concentration as well as the standard deviation of surface chlorophyll were used in conjunction with marine mammal sightings collected within Ecuadorian waters. Time lags between enhanced surface chlorophyll and marine mammal presence were on the order of 2-4 weeks, however correlations were much stronger when the standard deviation of spatially binned images was used, rather than the chlorophyll concentrations. Time lags also varied between Balaenopterid and Odontocete cetaceans. Overall, the standard deviation of surface chlorophyll proved a useful tool for assessing potential relationships between marine mammal sightings and surface chlorophyll.

  9. Ocean Water Column Probing Using LIDAR

    NASA Astrophysics Data System (ADS)

    Meijer, Sam; Bensky, Thomas

    2010-10-01

    California Polytechnic State University, San Luis Obispo operates a 1-km research pier extending due south over San Luis Obispo Bay, on the central coast of California, equidistant from both Los Angeles and San Francisco. The pier is situated 25 feet above the ocean surface where the water is approximately 30 feet deep. We have constructed a LIDAR station here that fires 10-ns, 1-Watt, 532-nm pulses from a YAG laser directly into the water at 20 Hz. A single photon detector placed near the laser aperture feeds a histogramming picosecond time analyzer that logs the return times of photons only at this wavelength. After a strong surface return, we observe photon return events that span a time interval corresponding to the maximum possible distance a photon can traverse in traveling from the laser to the ocean bottom and back to the detector. In estimating return signal strengths, the amount of laser light reflected from the ocean floor is an important parameter. To measure this, we have constructed a ``benthic reflectometer'' that, when lowered near the ocean floor, will allow for determination of the reflected light intensity from the floor itself. In this presentation we will report on photon return event spectra, benthic reflectance measurements and future plans.

  10. Water in Mantle Sources of Oceanic Basalts

    NASA Astrophysics Data System (ADS)

    Dixon, J. E.

    2006-12-01

    This talk will review estimates of water partitioning during subduction as determined by studies of mantle- derived melts. A major uncertainty in the earth's water cycle is the effect of subduction and recycling of hydrated lithosphere on deep mantle water concentrations. The problem with quantifying the variablility of mantle volatiles is that their concentrations are easily modified by shallow crystallization and degassing processes. Careful examination of volatile data from submarine basalts is required to select only those that have not degassed water. For example, even basalts collected deep on a submarine rift zone are not immune because basaltic volcanoes that have breached the sea surface are like champagne bottles; once the cork is popped, the entire bottle goes flat (e.g., Dixon et al., 1991). Once degassing effects have been eliminated, mantle water concentrations show systematic variations. Mantle sources for mid-ocean ridge basalts contain about 120 ppm water, with the most depleted MORB end-member having about 60 ppm. Source regions for mantle plumes are wetter than MORB sources. The wettest mantle is found in plumes dominated by the "common mantle plume component" (FOZO; 700 to 800 ppm H2O, H2O /Ce=210 to 300). Mantle sources for plumes enriched in recycled lithosphere (EM1, EM2, LOMU, and HIMU) have about half as much water (300 to 400 ppm H2O) and lower ratios of water to similarly incompatible elements (H2O/Ce<=100). High H2O /Ce in FOZO plumes cannot be derived from recycled lithosphere; therefore, a significant amount of water must be juvenile, left over from planetary accretion. Thus, dehydration during subduction effectively partitions water into the exosphere (mantle wedge, crust, ocean, atmosphere) resulting in time-integrated depletion of water relative to other incompatible elements in recycled (deeply subducted) lithosphere and sediments and, ultimately, the majority of the mantle. These results are consistent with a global water cycle

  11. OpenDA-NEMO framework for ocean data assimilation

    NASA Astrophysics Data System (ADS)

    van Velzen, Nils; Altaf, Muhammad Umer; Verlaan, Martin

    2016-05-01

    Data assimilation methods provide a means to handle the modeling errors and uncertainties in sophisticated ocean models. In this study, we have created an OpenDA-NEMO framework unlocking the data assimilation tools available in OpenDA for use with NEMO models. This includes data assimilation methods, automatic parallelization, and a recently implemented automatic localization algorithm that removes spurious correlations in the model based on uncertainties in the computed Kalman gain matrix. We have set up a twin experiment where we assimilate sea surface height (SSH) satellite measurements. From the experiments, we can conclude that the OpenDA-NEMO framework performs as expected and that the automatic localization significantly improves the performance of the data assimilation algorithm by successfully removing spurious correlations. Based on these results, it looks promising to extend the framework with new kinds of observations and work on improving the computational speed of the automatic localization technique such that it becomes feasible to include large number of observations.

  12. Direct detection of iodine oxide and glyoxal over the open tropical Pacific Ocean

    NASA Astrophysics Data System (ADS)

    Volkamer, R.; Coburn, S.; Dix, B. K.; Sinreich, R.

    2009-12-01

    A novel Ship Multi AXis DOAS (CU SMAX-DOAS) instrument, developed at CU Boulder’s Atmospheric Trace Molecule Spectroscopy Laboratory (AMTOSpeclab), was deployed from October 2008 to January 2009 on board NOAA’s RV Ronald H. Brown over the Eastern Pacific Ocean to directly probe the column abundance of iodine oxide (IO), iodine dioxide (OIO), bromine oxide (BrO), nitrogen dioxide (NO2), glyoxal (CHOCHO), and formaldehyde (HCHO), water vapor (H2O) and oxygen dimers (O4, an indicator for aerosol optical depth) as part of the VOCALS-REx field campaign. This contribution presents spectral proof for the direct detection of iodine oxide and CHOCHO in elevated concentrations concentrations over biologically active upwelling regions of the Pacific Ocean more than 3000km from the West Coast of South America. To our knowledge this is the first direct and simultaneous detection of IO and CHOCHO over the open ocean. Our measurements demonstrate that CHOCHO and IO are located inside the marine boundary layer, and can not be explained by continental outflow of precursor gases emitted over land. We discuss a possible source mechanism that is compatible with our observations, and points to an open ocean source that is not currently represented in atmospheric models.

  13. Atmospheric Response to Weddell Sea Open-Ocean Polynya

    SciTech Connect

    Hodos, Travis; Weijer, Wilbert

    2015-07-02

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

  14. Evaluation of Littoral Combat Ships for Open-Ocean Anti-Submarine Warfare

    DTIC Science & Technology

    2016-03-01

    distribution is unlimited EVALUATION OF LITTORAL COMBAT SHIPS FOR OPEN- OCEAN ANTI-SUBMARINE WARFARE by Team LCS Cohort 311-143O March 2016...March 2016 3. REPORT TYPE AND DATES COVERED Capstone project report 4. TITLE AND SUBTITLE EVALUATION OF LITTORAL COMBAT SHIPS FOR OPEN- OCEAN ...200 words) This report evaluates the Littoral Combat Ship (LCS) and its potential to fulfill the open- ocean anti- submarine warfare (ASW) mission

  15. Quantifying atmospheric processing of mineral dust as a source of bioavailable phosphorus to the open oceans

    NASA Astrophysics Data System (ADS)

    Herbert, Ross; Stockdale, Anthony; Carslaw, Ken; Krom, Michael

    2016-04-01

    The transport and deposition of mineral dust is known to be the dominant source of phosphorus (P) to the surface waters of the open oceans. However, the fraction of this P that is deemed available for primary productivity remains a key uncertainty due to a limited understanding of the processes occurring during transport of the dust. Through a series of detailed laboratory experiments using desert dust and dust precursors, we show that the dissolution behaviour of P in these samples is controlled by a surface-bound labile pool, and an additional mineral pool primarily consisting of apatite. The acid dissolution of the apatite occurs rapidly and is controlled by the absolute number of H+ ions present in the solution surrounding the dust. Using these results we develop a new conceptual model that reproduces the major processes controlling P dissolution in the atmosphere. We then use a global aerosol microphysics model with a global soil database to quantify the deposition of bioavailable P to the open oceans and ice sheets. We show that, globally, the labile pool contributes 2.4 Gg P a-1 to the oceans and, from a potential pool of 11.5 Gg P a-1, the dissolved apatite pool contributes 0.24 Gg P a-1. A series of sensitivity studies identifying sources of acid in the atmosphere show that anthropogenic emissions of SO2 contribute 61% of the global mass of dissolved apatite, volcanic events contribute 11%, and DMS emissions contribute 10%. Finally, we show that the fraction of mineral dust P that is available for primary productivity varies, regionally, from <20% in the North Atlantic Ocean to >50% in the South Pacific Ocean; this explains the variability in the fraction of bioavailable P commonly observed in important oceanic regions.

  16. Airborne ocean water lidar (OWL) real time processor (RTP)

    NASA Astrophysics Data System (ADS)

    Hryszko, M.

    1995-03-01

    The Hyperflo Real Time Processor (RTP) was developed by Pacific-Sierra Research Corporation as a part of the Naval Air Warfare Center's Ocean Water Lidar (OWL) system. The RTP was used for real time support of open ocean field tests at Barbers Point, Hawaii, in March 1993 (EMERALD I field test), and Jacksonville, Florida, in July 1994 (EMERALD I field test). This report describes the system configuration, and accomplishments associated with the preparation and execution of these exercises. This document is intended to supplement the overall test reports and provide insight into the development and use of the PTP. A secondary objective is to provide basic information on the capabilities, versatility and expandability of the Hyperflo RTP for possible future projects. It is assumed herein that the reader has knowledge of the OWL system, field test operations, general lidar processing methods, and basic computer architecture.

  17. OpenDrift - an open source framework for ocean trajectory modeling

    NASA Astrophysics Data System (ADS)

    Dagestad, Knut-Frode; Breivik, Øyvind; Ådlandsvik, Bjørn

    2016-04-01

    We will present a new, open source tool for modeling the trajectories and fate of particles or substances (Lagrangian Elements) drifting in the ocean, or even in the atmosphere. The software is named OpenDrift, and has been developed at Norwegian Meteorological Institute in cooperation with Institute of Marine Research. OpenDrift is a generic framework written in Python, and is openly available at https://github.com/knutfrode/opendrift/. The framework is modular with respect to three aspects: (1) obtaining input data, (2) the transport/morphological processes, and (3) exporting of results to file. Modularity is achieved through well defined interfaces between components, and use of a consistent vocabulary (CF conventions) for naming of variables. Modular input implies that it is not necessary to preprocess input data (e.g. currents, wind and waves from Eulerian models) to a particular file format. Instead "reader modules" can be written/used to obtain data directly from any original source, including files or through web based protocols (e.g. OPeNDAP/Thredds). Modularity of processes implies that a model developer may focus on the geophysical processes relevant for the application of interest, without needing to consider technical tasks such as reading, reprojecting, and colocating input data, rotation and scaling of vectors and model output. We will show a few example applications of using OpenDrift for predicting drifters, oil spills, and search and rescue objects.

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

    PubMed

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

    2012-01-01

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

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

    PubMed Central

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

    2012-01-01

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

  20. Open-ocean boundary conditions from interior data: Local and remote forcing of Massachusetts Bay

    USGS Publications Warehouse

    Bogden, P.S.; Malanotte-Rizzoli, P.; Signell, R.

    1996-01-01

    Massachusetts and Cape Cod Bays form a semienclosed coastal basin that opens onto the much larger Gulf of Maine. Subtidal circulation in the bay is driven by local winds and remotely driven flows from the gulf. The local-wind forced flow is estimated with a regional shallow water model driven by wind measurements. The model uses a gravity wave radiation condition along the open-ocean boundary. Results compare reasonably well with observed currents near the coast. In some offshore regions however, modeled flows are an order of magnitude less energetic than the data. Strong flows are observed even during periods of weak local wind forcing. Poor model-data comparisons are attributable, at least in part, to open-ocean boundary conditions that neglect the effects of remote forcing. Velocity measurements from within Massachusetts Bay are used to estimate the remotely forced component of the flow. The data are combined with shallow water dynamics in an inverse-model formulation that follows the theory of Bennett and McIntosh [1982], who considered tides. We extend their analysis to consider the subtidal response to transient forcing. The inverse model adjusts the a priori open-ocean boundary condition, thereby minimizing a combined measure of model-data misfit and boundary condition adjustment. A "consistency criterion" determines the optimal trade-off between the two. The criterion is based on a measure of plausibility for the inverse solution. The "consistent" inverse solution reproduces 56% of the average squared variation in the data. The local-wind-driven flow alone accounts for half of the model skill. The other half is attributable to remotely forced flows from the Gulf of Maine. The unexplained 44% comes from measurement errors and model errors that are not accounted for in the analysis. 

  1. Characteristics of elite open-water swimmers.

    PubMed

    VanHeest, Jaci L; Mahoney, Carrie E; Herr, Larry

    2004-05-01

    Open-water swimming (5, 10, and 25 km) has many unique challenges that separate it from other endurance sports, like marathon running and cycling. The characteristics of a successful open-water swimmer are unclear. The purpose of this study was to determine the physical and metabolic characteristics of a group of elite-level open-water swimmers. The open-water swimmers were participating in a 1-week training camp. Anthropometric, metabolic, and blood chemistry assessments were performed on the athletes. The swimmers had a VO(2)peak of 5.51 +/- 0.96 and 5.06 +/- 0.57 ml.kg(-1).min(-1) for males and females, respectively. Their lactate threshold (LT) occurred at a pace equal to 88.75% of peak pace for males and 93.75% for females. These elite open-water swimmers were smaller and lighter than competitive pool swimmers. They possess aerobic metabolic alterations that resulted in enhanced performance in distance swimming. Trainers and coaches should develop dry-land programs that will improve the athlete's muscular endurance. Furthermore, programs should be designed to increase the LT velocity as a percentage of peak swimming velocity.

  2. Open-ocean convection becoming less intense in the Greenland and Iceland Seas

    NASA Astrophysics Data System (ADS)

    Moore, Kent; Vage, Kjetil; Pickart, Robert; Renfrew, Ian

    2014-05-01

    The air-sea transfer of heat and freshwater plays a critical role in the global climate system. This is particularly true for the Greenland and Iceland Seas, where these fluxes drive open-ocean convection that contributes to Denmark Strait Overflow Water, the densest component of the lower limb of the Atlantic Meridional Overturning Circulation (AMOC). This buoyancy transfer is most pronounced during the winter downstream of the ice edge, where the cold and dry Arctic air first comes in contact with the relatively warm ocean surface. In this talk, we show that the observed wintertime retreat of sea ice in the region, which is exposing more of the ocean to interactions with the atmosphere, has led to a differential surface warming of the Greenland and Iceland Seas resulting in reductions of 15% and 25% in the magnitude of the respective air-sea heat fluxes since 1979. Model simulations show that further decreases in atmospheric forcing will cross a threshold for the Greenland Sea whereby convection will be depth limited, reducing the ventilation of mid-depth waters in the Nordic Seas. In the Iceland Sea, such reductions in atmospheric forcing will decrease the supply of the densest overflow waters to the AMOC.

  3. The Cretaceous opening of the South Atlantic Ocean

    NASA Astrophysics Data System (ADS)

    Granot, Roi; Dyment, Jérôme

    2015-03-01

    The separation of South America from Africa during the Cretaceous is poorly understood due to the long period of stable polarity of the geomagnetic field, the Cretaceous Normal Superchron (CNS, lasted between ∼121 and 83.6 Myr ago). We present a new identification of magnetic anomalies located within the southern South Atlantic magnetic quiet zones that have arisen due to past variations in the strength of the dipolar geomagnetic field. Using these anomalies, together with fracture zone locations, we calculate the first set of magnetic anomalies-based finite rotation parameters for South America and Africa during that period. The kinematic solutions are generally consistent with fracture zone traces and magnetic anomalies outside the area used to construct them. The rotations indicate that seafloor spreading rates increased steadily throughout most of the Cretaceous and decreased sharply at around 80 Myr ago. A change in plate motion took place in the middle of the superchron, roughly 100 Myr ago, around the time of the final breakup (i.e., separation of continental-oceanic boundary in the Equatorial Atlantic). Prominent misfit between the calculated synthetic flowlines (older than Anomaly Q1) and the fracture zones straddling the African Plate in the central South Atlantic could only be explained by a combination of seafloor asymmetry and internal dextral motion (<100 km) within South America, west of the Rio Grande fracture zone. This process has lasted until ∼92 Myr ago after which both Africa and South America (south of the equator) behaved rigidly. The clearing of the continental-oceanic boundaries within the Equatorial Atlantic Gateway was probably completed by ∼95 Myr ago. The clearing was followed by a progressive widening and deepening of the passageway, leading to the emergence of north-south flow of intermediate and deep-water which might have triggered the global cooling of bottom water and the end for the Cretaceous greenhouse period.

  4. Scandium in the open ocean: A comparison with other group 3 trivalent metals

    NASA Astrophysics Data System (ADS)

    Parker, C. E.; Brown, M. T.; Bruland, K. W.

    2016-03-01

    Little is known about the distribution of scandium (Sc) in the open ocean. Since the 1970s there has been only one published depth profile of dissolved Sc. The work presented here reports depth profiles of dissolved Sc from GEOTRACES cruises in the North Atlantic, North Pacific, and South Pacific. This work also compares the reactivity of Sc with its trivalent periodic table groupmates in Group IIIB, yttrium (Y) and lanthanum (La), and Group IIIA, aluminum (Al) and gallium (Ga). Yttrium and La are classic nutrient-type metals that increase in concentration in aging deep water; Al and Ga are classic scavenged-type metals that do the opposite. Results indicate that Sc is a hybrid-type metal with an inferred residence time on the order of 1000 years, and that Sc's inorganic speciation and reactivity are similar to Fe's and have the potential to give insights into the nonnutrient side of oceanic Fe cycling.

  5. Physical processes that enhance nutrient transport and primary productivity in the coastal and open ocean of the subarctic NE Pacific

    NASA Astrophysics Data System (ADS)

    Whitney, F. A.; Crawford, W. R.; Harrison, P. J.

    2005-03-01

    In comparison to the open ocean, several additional processes including coastal upwelling, river discharge, tidal mixing, estuarine circulation and benthic remineralization enhance nutrient supply to the surface waters of the continental shelf. In general, coastal waters become nitrate-limited during the phytoplankton growing season, whereas iron and dissolved silicate limit phytoplankton growth in the less productive oceanic waters of the Gulf of Alaska. If coastal processes supply ample amounts of macro and micro nutrients during the growing season, diatom communities dominated by species such as Skeletomema costatum, Chaetoceros spp. and Thalassiosira spp. will bloom. Growth rates of these bloom populations typically range from 0.5 to >1.5 doublings per day, which place a high demand on nutrients. Any transport of coastal waters away from the shelf will enhance productivity in oceanic waters. The general circulation of the eastern subarctic Pacific does not allow for offshore transport except in special circumstances. These include anticyclonic mesoscale eddy formation, which can export as much as 5000 km 3 of nutrient-rich waters from the shelf in a single eddy, and recirculation of waters away from southwestern Alaska due to the cyclonic circulation around the western edge of the Alaskan Gyre. Recirculation can carry nutrient-rich water from the coast to the vicinity of Ocean Station Papa (50°N, 145°W) within a few months. For both eddies and gyre recirculation, much of the water being carried into the open ocean lies below the euphotic zone. Iron enrichment occurs to a depth of at least 1000 m in the Gulf of Alaska as a result. Periods of enhanced eddy formation or recirculation may supply iron that enriches the open ocean for several years. Damming of the Columbia River and human uses of its waters have resulted in more winter and less summer discharge of fresh water and dissolved Si. Coastal currents in this area flow north in winter and south in summer

  6. Cycling of PCBs and HCB in the surface ocean-lower atmosphere of the open Pacific.

    PubMed

    Zhang, Lin; Lohmann, Rainer

    2010-05-15

    Surface ocean and lower atmosphere samples were collected on the R/V Revelle during a scientific cruise from San Diego, CA to New Zealand via Samoa and the South Pacific Gyre (SPG) from 12/2006 to 1/2007. Samples were analyzed for polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB). summation operator(ICES)PCBs gaseous concentrations (ICES: International Council for the Exploration of the Sea) ranged from 28-103 pg m(-3) in the northern hemisphere (NH) and 1.5-36 pg m(-3) in the southern hemisphere (SH), whereas dissolved seawater concentrations were between 0.2-15 pg L(-1) in the NH and 0.3-7.8 pg L(-1) in the SH. Both gas ([PCBs](gas)) and dissolved phase concentrations ([PCBs](sw_dis)) displayed highest concentrations near North America and lowest in the SPG. In the NH, [HCB](gas) ranged from 42-89 pg m(-3), higher than the average in the SH (31 pg m(-3)), while [HCB](sw_dis) were comparable in both hemispheres (NH: 0.4-1.6 pg L(-1), SH: 0.4-0.8 pg L(-1)). Fugacity ratio calculations suggest PCBs were volatilizing from surface waters to the overlying atmosphere, and air-water exchange fluxes were approximately 0.5 to approximately 30.4 ng m(-2) d(-1). This is the first study reporting the degassing of PCBs from the open ocean into the air. Previous studies deduced net deposition of PCBs into the Atlantic and Arctic Oceans. As has been observed for other oceans, HCB was at/near air-water equilibrium. A mass balance model was used to interpret the short-term variations in [PCBs](gas) in the SPG, which was not observed for HCB. It is suggested that hydroxyl radical depletion reaction and air-water gas exchange together controlled the variation in [PCBs](gas).

  7. Significant contribution of large particles to optical backscattering in the open ocean

    NASA Astrophysics Data System (ADS)

    Dall'Olmo, G.; Westberry, T. K.; Behrenfeld, M. J.; Boss, E.; Slade, W. H.

    2009-06-01

    The light scattering properties of oceanic particles have been suggested as an alternative index of phytoplankton biomass than chlorophyll-a concentration (chl-a), with the benefit of being less sensitive to physiological forcings (e.g., light and nutrients) that alter the intracellular pigment concentrations. The drawback of particulate scattering is that it is not unique to phytoplankton. Nevertheless, field studies have demonstrated that, to first order, the particulate beam-attenuation coefficient (cp) can track phytoplankton biomass. The relationship between cp and the particulate backscattering coefficient (bbp), a property retrievable from space, has not been fully evaluated, largely due to a lack of open-ocean field observations. Here, we present extensive data on inherent optical properties from the Equatorial Pacific surface waters and demonstrate a remarkable coherence in bbp and cp. Coincident measurements of particle size distributions (PSDs) and optical properties of size-fractionated samples indicate that this covariance is due to both the conserved nature of the PSD and a greater contribution of phytoplankton-sized particles to bbp than theoretically predicted. These findings suggest that satellite-derived bbpcould provide similar information on phytoplankton biomass in the open ocean as cp.

  8. Direct contribution of phytoplankton-sized particles to optical backscattering in the open ocean

    NASA Astrophysics Data System (ADS)

    Dall'Olmo, G.; Westberry, T. K.; Behrenfeld, M. J.; Boss, E.; Slade, W. H.

    2009-01-01

    Light scattering properties of oceanic particles have been suggested as an alternative index of phytoplankton biomass than chlorophyll-a concentration (chl-a), with the benefit of being less sensitive to physiological forcings (e.g., light and nutrients) that alter the intracellular pigment concentrations. The drawback of particulate scattering is that it is not unique to phytoplankton. Nevertheless, field studies have demonstrated that, to first order, the particulate beam-attenuation coefficient (cp) can track phytoplankton abundance. The relationship between cp and the particulate backscattering coefficient (bbp), a property retrievable from space, has not been fully evaluated, largely due to a lack of open-ocean field observations. Here, we present extensive data on inherent optical properties from the Equatorial Pacific surface waters and demonstrate a remarkable coherence in bbp and cp. Coincident measurements of particle size distributions (PSDs) and optical properties of size-fractionated samples indicate that this covariance is due to both the conserved nature of the PSD and a greater contribution of phytoplankton-sized particles to bbp than theoretically predicted. These findings suggest that satellite-derived bbp could provide similar information on phytoplankton biomass in the open ocean as cp.

  9. Deep sediment resuspension and thick nepheloid layer generation by open-ocean convection

    NASA Astrophysics Data System (ADS)

    Durrieu de Madron, X.; Ramondenc, S.; Berline, L.; Houpert, L.; Bosse, A.; Martini, S.; Guidi, L.; Conan, P.; Curtil, C.; Delsaut, N.; Kunesch, S.; Ghiglione, J. F.; Marsaleix, P.; Pujo-Pay, M.; Séverin, T.; Testor, P.; Tamburini, C.

    2017-03-01

    The Gulf of Lions in the northwestern Mediterranean is one of the few sites around the world ocean exhibiting deep open-ocean convection. Based on 6 year long (2009-2015) time series from a mooring in the convection region, shipborne measurements from repeated cruises, from 2012 to 2015, and glider measurements, we report evidence of bottom thick nepheloid layer formation, which is coincident with deep sediment resuspension induced by bottom-reaching convection events. This bottom nepheloid layer, which presents a maximum thickness of more than 2000 m in the center of the convection region, probably results from the action of cyclonic eddies that are formed during the convection period and can persist within their core while they travel through the basin. The residence time of this bottom nepheloid layer appears to be less than a year. In situ measurements of suspended particle size further indicate that the bottom nepheloid layer is primarily composed of aggregates between 100 and 1000 µm in diameter, probably constituted of fine silts. Bottom-reaching open ocean convection, as well as deep dense shelf water cascading that occurred concurrently some years, lead to recurring deep sediments resuspension episodes. They are key mechanisms that control the concentration and characteristics of the suspended particulate matter in the basin, and in turn affect the bathypelagic biological activity.

  10. The influence of the Sunda Strait opening on paleoenvironmental changes in the eastern Indian Ocean

    NASA Astrophysics Data System (ADS)

    Xu, Yonghang; Wang, Liang; Yin, Xijie; Ye, Xiang; Li, Dongyi; Liu, Shengfa; Shi, Xuefa; Troa, Rainer Arief; Zuraida, Rina; Triarso, Eko; Hendrizan, Marfasran

    2017-09-01

    With sea level rise in the early Holocene, the warm and low-salinity sea water from the Java Sea was transported into the eastern Indian Ocean after the opening of the Sunda Strait. However, the impact of this process on sediment provenance and paleoproductivity is rarely known. In this study, we analyzed the grain size, Sr-Nd-Pb isotopic compositions and biogenic elements of core CJ01-185 (1538 m water depth) in the eastern Indian Ocean off the Sunda Strait. Our new results reveal a large volcanic eruption in the west of Java at 2.1 ka, and the Krakatau eruption at 1883 CE. On the basis of the Pb isotopic compositions, 87Sr/86Sr ratios, and εNd values, we infer that sediments from core CJ01-185 were derived primarily from Java Island. There is a distinct change in Sr-Nd-Pb isotopic compositions of the sediments from the last glacial period to the Holocene, indicating less radiogenic Nd isotopes from the Java Sea into the eastern Indian Ocean after the opening of the Sunda Strait at ∼10 ka. Moreover, the sedimentation rate increased significantly from 6.5 cm kyr-1 during the last glacial period to 20 cm kyr-1 in the Holocene. The input of additional terrigenous nutrients from the Java Sea induced paleoproductivity with higher TOC and TN concentrations after the opening of the Sunda Strait. Our results thus suggest that the paleoproductivity was mainly influenced by terrigenous materials input in the Holocene, other than southeast monsoon or upwelling in the last glacial period.

  11. Epicontinental seas versus open-ocean settings: the kinetics of mass extinction and origination.

    PubMed

    Miller, Arnold I; Foote, Michael

    2009-11-20

    Environmental perturbations during mass extinctions were likely manifested differently in epicontinental seas than in open-ocean-facing habitats of comparable depth. Here, we present a dissection of origination and extinction in epicontinental seas versus open-ocean-facing coastal regions in the Permian through Cretaceous periods, an interval through which both settings are well represented in the fossil record. Results demonstrate that extinction rates were significantly higher in open-ocean settings than in epicontinental seas during major mass extinctions but not at other times and that origination rates were significantly higher in open-ocean settings for a protracted interval from the Late Jurassic through the Late Cretaceous. These patterns are manifested even when other paleogeographic and environmental variables are held fixed, indicating that epicontinental seas and open-ocean-facing coastlines carry distinct macroevolutionary signatures.

  12. Eddies as trigger for diatom productivity in the open-ocean Northeast Atlantic

    NASA Astrophysics Data System (ADS)

    Romero, Oscar E.; Fischer, Gerhard; Karstensen, Johannes; Cermeño, Pedro

    2016-09-01

    Anticyclonic mesoscale eddies (ACME) have been proposed as a mechanism by which new nutrients are episodically delivered into the euphotic zone, thereby enhancing new production as well as shifting phytoplankton community structure. In this paper, we report on a 34-month sediment trap experiment at the Cape Verde Ocean Observatory (CVOO; ca. 18°N, 24°E; December 2009-October 2012), occasionally influenced by ACME passages. The typically oligotrophic, weakly seasonal particle flux pattern at the CVOO is strongly modified by the appearance of a highly productive and low oxygen ACME. Out of four recorded diatom flux maxima at CVOO, three were associated with the passage of ACMEs. The recorded diatom maxima events support the view that local ACME dynamics promotes upward nutrient supply into the euphotic zone leading to a rapid response of diatoms. This response is clearly reflected by the flux seasonality: between 40% and 60% of the total annual diatom flux at the CVOO site was intercepted in a relatively short time interval (<60 days). A highly diverse diatom community characterized the diatom fluxes throughout. Along with the ACME passages, small species of the genus Nitzschia, and Thalassionema nitzschioides var. parva dominated and delivered a major portion of the opal and organic carbon into deeper waters at site CVOO. Several pelagic, warm-water background species became dominant during intervals with low nutrient availability in the euphotic zone. Results of our interannual time-series suggest that ACMEs impact on total diatom production and the species-specific composition of the assemblage north of the Cave Verde Islands, and can strengthen the biological pump in open-ocean, oligotrophic subtropical regions of the world ocean. Our observations are useful for testing biogeochemical ocean models and will also help in improving the knowledge of processes and mechanisms behind interannual time-series of bulk components and microorganisms in pelagic and

  13. Bottom water warming in the North Pacific Ocean.

    PubMed

    Fukasawa, Masao; Freeland, Howard; Perkin, Ron; Watanabe, Tomowo; Uchida, Hiroshi; Nishina, Ayako

    2004-02-26

    Observations of changes in the properties of ocean waters have been restricted to surface or intermediate-depth waters, because the detection of change in bottom water is extremely difficult owing to the small magnitude of the expected signals. Nevertheless, temporal changes in the properties of such deep waters across an ocean basin are of particular interest, as they can be used to constrain the transport of water at the bottom of the ocean and to detect changes in the global thermohaline circulation. Here we present a comparison of a trans-Pacific survey completed in 1985 (refs 4, 5) and its repetition in 1999 (ref. 6). We find that the deepest waters of the North Pacific Ocean have warmed significantly across the entire width of the ocean basin. Our observations imply that changes in water properties are now detectable in water masses that have long been insulated from heat exchange with the atmosphere.

  14. Manganese and iron in Indian Ocean waters

    SciTech Connect

    Saager, P.M.; De Baar, H.J.W. ); Burkill, P.H. )

    1989-09-01

    The first vertical profiles of dissolved Mn and Fe for the (NW) Indian Ocean are reported. The area is characterized by seasonal upwelling and a broad oxygen minimum zone in intermediate waters. The dissolved Fe-profile exhibits a maximum (5.1 nM) in the oxygen minimum zone, with low values both in surface waters (0.3 nM) and deep waters (around 1 nM). Mn concentrations in the surface waters are elevated (2.0-4.3 nM), and decrease rapidly in an offshore direction. Below the first 25 m, concentrations decrease dramatically (0.5-1.3 nM), indicating removal by oxidation and particle scavenging. Further down, various Mn maxima are observed which can be related to hydrographic features. The include the facts that: intermediate water originating from the Red Sea lost its dissolved O{sub 2} while flowing northward along the Omani coast and exhibits a strong Mn maximum (4.6-6.5 nM) coincident with the deep O{sub 2} minimum; at the two inshore stations in the Gulf of Oman this is overlain by relatively modest Mn maxima ({plus minus}2.7 nM) related to Arabian Gulf overflow water; and the strong Mn maxima (4.4-5.6 nM) in the oxygen minimum zone at the two offshore stations are related to yet another watermass. Below these various maxima, concentrations decrease gradually to values as low as 90 pM at 2,000 meters depth. Towards the sea floor concentrations increase again, leading to a modest bottom water maximum (0.7-1.5 nM). The overall vertical distributions of Mn and Fe are strikingly similar, also in actual concentrations, to those previously reported for the eastern equatorial Pacific, an area also characterized by an extensive O{sub 2}-minimum zone.

  15. Optimisation methods for bathymetry and open boundary conditions in finite element model of ocean tides

    SciTech Connect

    Lyard, F.; Genco, M.L.

    1994-10-01

    A bidimensional, spectral in time, quasi-linearised hydrodynamic ocean tide model has been developed at the Institut de Mecanique de Grenoble. This model is derived from the classical shallow water equations by removing the velocity unknowns in the continuity equation, that leads to an elliptic, second-order differential equation where tide denivellation remains the only unknown quantity. The problem is solved in its variational formulation and the finite elements method is used to discretise the equations in the spatial domain with a Lagrange-P2 approximation. Bottom topography has to be known at the integration points of the elements. In the case of the large oceanic basins, a specific method, called the bathymetry optimisation method, is needed to correctly take into account the bottom topography inside the model. The accuracy of the model`s solutions is also strongly dependent on the quality of the open boundary conditions because of the elliptic characteristics of the problem. The optimisation method for open boundary conditions relies on the use of the in situ data available in the modelled domain. The aim of this paper is to present the basis of these optimisations of bathymetry and open boundary conditions. An illustration of the related improvements is presented on the North Atlantic Basin. 36 refs., 10 figs., 5 tabs.

  16. Impact of open-ocean convection on nutrients, phytoplankton biomass and activity

    NASA Astrophysics Data System (ADS)

    Severin, T.; Conan, P.; Durrieu de Madron, X.; Houpert, L.; Oliver, M. J.; Oriol, L.; Caparros, J.; Ghiglione, J. F.; Pujo-Pay, M.

    2014-12-01

    We describe the impact of an open-ocean convection event on nutrient budgets, carbon budget, elemental stoichiometry, phytoplankton biomass and activity in the Northwestern Mediterranean Sea (NWM). In the convective episode examined here we estimated an input of nutrients to the surface layer of 7.0, 8.0 and 0.4×108 mol of silicate, nitrate and phosphate, respectively. These quantities correspond to the annual nutrient input by river discharges and atmospheric depositions in the Gulf of Lion. Such nutrient input is sufficient to sustain new primary production from 46 to 63 g C m-2 y-1, which is the same order of magnitude found in the NWM open waters. Our results together with satellite data analysis, propose new scenarios that explain the origin of the spring phytoplankton bloom occurring in NWM.

  17. Nitrogen cycle of the open ocean: from genes to ecosystems.

    PubMed

    Zehr, Jonathan P; Kudela, Raphael M

    2011-01-01

    The marine nitrogen (N) cycle controls the productivity of the oceans. This cycle is driven by complex biogeochemical transformations, including nitrogen fixation, denitrification, and assimilation and anaerobic ammonia oxidation, mediated by microorganisms. New processes and organisms continue to be discovered, complicating the already complex picture of oceanic N cycling. Genomics research has uncovered the diversity of nitrogen metabolism strategies in phytoplankton and bacterioplankton. The elemental ratios of nutrients in biological material are more flexible than previously believed, with implications for vertical export of carbon and associated nutrients to the deep ocean. Estimates of nitrogen fixation and denitrification continue to be modified, and anaerobic ammonia oxidation has been identified as a new process involved in denitrification in oxygen minimum zones. The nitrogen cycle in the oceans is an integral feature of the function of ocean ecosystems and will be a central player in how oceans respond during global environmental change.

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

    NASA Astrophysics Data System (ADS)

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

    2011-10-01

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

  19. Oceans of Water in the Earth's core

    NASA Astrophysics Data System (ADS)

    Saxena, S. K.; Dubrovinsky, L.; Rekhi, S.; Wang, Z.; Shen, G.

    2002-05-01

    to high pressures (~85 GPa) and temperatures (~1800 K) and therefore it could form in a primitive iron core and become a part of the melt if temperature exceeds the melting temperature (~2000 K) at the outer-core press, and b) in the system iron-water, the hydride phase cannot exist without wuestite and therefore both hydrogen and oxygen components will be part of the melt in the outer core. An additional important result is that we could not determine the influence of water on direct melting of iron because of the hydride and oxide reactions that preceded melting. Wuestite (FexO) or ferropericlase (a solid solution between periclase and wuestite) melted below 1525 K in presence of water. Wuestite is estimated to be present in abundance in the mantle and could be an important constituent of the primitive earth forming by direct reaction between iron and water. Although in this experiment, we can only ascertain that Fe was first oxidized and then melted, it does give us an estimate of the possible effect of water on the melting of Fe. According to Boehler, dry FeO melts at a temperature of ~2500 K at a pressure of 35 GPa. Thus water reduced the melting temperature of the pure phase by close to 1000 K. If the melting temperature of iron is similarly reduced in a fluid saturated system, the effect could be large; in a less saturated system it may lower the melting by a few hundred degrees. If even a percent of water in the core will amount to ten times more water than that present in the oceans.

  20. Stable isotopes in surface waters of the Atlantic Ocean: Indicators of ocean-atmosphere water fluxes and oceanic mixing processes

    NASA Astrophysics Data System (ADS)

    Benetti, M.; Reverdin, G.; Aloisi, G.; Sveinbjörnsdóttir, Á.

    2017-06-01

    The surface ocean hydrological cycle is explored based on ˜300 new δ18O and δD measurements from surface waters of the Atlantic Ocean and the Mediterranean Sea over the period 2010-2016. Our approach combines these surface observations with salinity (S) and stable isotope measurements of atmospheric water vapor. The distinct regional S-δ distributions are used to identify different surface water masses and their horizontal advection. Moreover, based on assumptions on the δ-S characteristics of seawater sources and the isotope composition of the evaporative (δe) and meteoric water (δMW) fluxes, the δ-S distribution is used to indicate the relative importance of evaporation (E) and meteoric water inputs (MW). Here δe is estimated from the Craig and Gordon's equation using 120 days of measurements of the ambient air above the Atlantic Ocean collected during three cruises. To provide quantitative estimates of the E:MW ratio, we use the box model from Craig and Gordon (1965). This identifies the subtropical gyre as a region where E:MW ˜2 and the tropical ocean as a region were MW:E ˜2. Finally, we show that the δ18O-δD distribution is better represented by a linear fit than the δ-S relationship, even in basins governed by different hydrological processes. We interpret the δ18O-δD distribution considering the kinetic fractionation processes associated with evaporation. In the tropical region where MW exceeds E, the δ18O-δD distribution identifies the MW inputs from their kinetic signature, whereas in regions where E exceeds MW, the δ18O-δD distribution traces the humidity at the sea surface.

  1. Seawater test results of Open-Cycle Ocean Thermal Energy Conversion (OC-OTEC) components

    NASA Astrophysics Data System (ADS)

    Zangrando, F.; Bharathan, D.; Link, H.; Panchal, C. B.

    Key components of open-cycle ocean thermal energy conversion systems- the flash evaporator, mist eliminator, passive predeaerator, two surface condenser stages, and two direct-contact condenser stages- have been tested using seawater. These components operate at lower steam pressures and higher inlet noncondensable gas concentrations than do conventional power plant heat exchangers. The rate of heat exchanged between the evaporator and the condenser is on the order of 1.25MW-thermal, requiring a warm seawater flow of about 0.1 cu m/s; the cold seawater flow is on the order of half the warm water flow. In addition to characterizing the performance of the various components, the system has produced potable water from condensation of the steam produced in the evaporator. The information obtained in these tests is being used to design a larger scale experiment in which net power production is expected to be demonstrate for the first time using OC-OTEC technology.

  2. The impact of atmospheric aerosols on trace metal chemistry in open ocean surface seawater, 1. Aluminum

    NASA Astrophysics Data System (ADS)

    Maring, H. B.; Duce, R. A.

    1987-08-01

    Significant quantities of aerosol aluminum are transported from continental regions through the atmosphere to the oceans. Enrichments in the concentration of dissolved aluminum in open ocean surface seawater suggest that dissolution of aerosol aluminum is an important source of dissolved aluminum to these waters. Atmospheric aerosols collected at Enewetak Atoll were exposed to seawater and artificial rain water to determine directly the importance of atmospheric deposition as a source of marine dissolved aluminum. The results of these experiments indicate that ˜ 8-10% of the aluminum in atmospheric aerosols of crustal origin over the North Pacific is soluble in seawater. Approximately 5-6% dissolves very rapidly ( < 0.6 hr). An additional 3-4% dissolves within 60 hr. This bimodal dissolution of aerosol aluminum of crustal origin suggests that this aluminum is present in two forms. The rapidly dissolving fraction is likely aluminum already weathered from primary minerals, while the more slowly dissolving fraction is probably aluminum from the aluminosilicate matrix. Nearly the same amount of aerosol aluminum dissolved in artificial rain water ( pH= 5.5) in 6 hr as dissolved in seawater ( pH= 8) in 60 hr. The lower pH appears to not only increase the dissolution rate but may also increase the quantity of aerosol aluminum that dissolves. Dissolved organic matter in seawater appears to have relatively little effect on aerosol aluminum dissolution. Considering measured total aerosol aluminum fluxes, aluminum dissolution of 5-10% would constitute the major source for dissolved aluminum in surface waters of the open North Pacific. The calculated residence time of dissolved aluminum in the upper 100 m of the tropical North Pacific ranges from 2 to 6 years.

  3. Coastal Ocean Observing Network - Open Source Architecture for Data Management and Web-Based Data Services

    NASA Astrophysics Data System (ADS)

    Pattabhi Rama Rao, E.; Venkat Shesu, R.; Udaya Bhaskar, T. V. S.

    2012-07-01

    The observations from the oceans are the backbone for any kind of operational services, viz. potential fishing zone advisory services, ocean state forecast, storm surges, cyclones, monsoon variability, tsunami, etc. Though it is important to monitor open Ocean, it is equally important to acquire sufficient data in the coastal ocean through coastal ocean observing systems for re-analysis, analysis and forecast of coastal ocean by assimilating different ocean variables, especially sub-surface information; validation of remote sensing data, ocean and atmosphere model/analysis and to understand the processes related to air-sea interaction and ocean physics. Accurate information and forecast of the state of the coastal ocean at different time scales is vital for the wellbeing of the coastal population as well as for the socio-economic development of the country through shipping, offshore oil and energy etc. Considering the importance of ocean observations in terms of understanding our ocean environment and utilize them for operational oceanography, a large number of platforms were deployed in the Indian Ocean including coastal observatories, to acquire data on ocean variables in and around Indian Seas. The coastal observation network includes HF Radars, wave rider buoys, sea level gauges, etc. The surface meteorological and oceanographic data generated by these observing networks are being translated into ocean information services through analysis and modelling. Centralized data management system is a critical component in providing timely delivery of Ocean information and advisory services. In this paper, we describe about the development of open-source architecture for real-time data reception from the coastal observation network, processing, quality control, database generation and web-based data services that includes on-line data visualization and data downloads by various means.

  4. Atmospheric correction of AVIRIS data in ocean waters

    NASA Technical Reports Server (NTRS)

    Terrie, Gregory; Arnone, Robert

    1992-01-01

    Hyperspectral data offers unique capabilities for characterizing the ocean environment. The spectral characterization of the composition of ocean waters can be organized into biological and terrigenous components. Biological photosynthetic pigments in ocean waters have unique spectral ocean color signatures which can be associated with different biological species. Additionally, suspended sediment has different scattering coefficients which result in ocean color signatures. Measuring the spatial distributions of these components in the maritime environments provides important tools for understanding and monitoring the ocean environment. These tools have significant applications in pollution, carbon cycle, current and water mass detection, location of fronts and eddies, sewage discharge and fate etc. Ocean color was used from satellite for describing the spatial variability of chlorophyll, water clarity (K(sub 490)), suspended sediment concentration, currents etc. Additionally, with improved atmospheric correction methods, ocean color results produced global products of spectral water leaving radiance (L(sub W)). Ocean color results clearly indicated strong applications for characterizing the spatial and temporal variability of bio-optical oceanography. These studies were largely the results of advanced atmospheric correction techniques applied to multispectral imagery. The atmosphere contributes approximately 80 percent - 90 percent of the satellite received radiance in the blue-green portion of the spectrum. In deep ocean waters, maximum transmission of visible radiance is achieved at 490nm. Conversely, nearly all of the light is absorbed by the water at wavelengths greater than about 650nm and thus appears black. These spectral ocean properties are exploited by algorithms developed for the atmospheric correction used in satellite ocean color processing. The objective was to apply atmospheric correction techniques that were used for procesing satellite Coastal

  5. Open Ocean and Landfalling Hurricane Directional Wave Spectra from a Scanning Radar Altimeter

    NASA Technical Reports Server (NTRS)

    Wright, C. Wayne; Busalacchi, Antonio J. (Technical Monitor)

    2000-01-01

    The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in open water using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the National Oceanic and Atmospheric Administration (NOAA) WP-3D hurricane research aircraft at 1.5 km height. The open-ocean data were acquired on 24 August 1998 when Bonnie, a large category 3 hurricane, was east of the Bahamas and moving about 5 meters per second toward 330. The NOAA aircraft spent over five hours within 180 km of the hurricane Bonnie eye and made five eye penetrations. Individual waves with heights up to 18 m were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At some positions there were three different wave fields of comparable energy crossing each other. On 26 August 1998, the SRA documented the wave spectrum spatial variation while Bonnie was making landfall near Wilmington, NC.

  6. Hidden biosphere in an oxygen-deficient Atlantic open ocean eddy: future implications of ocean deoxygenation on primary production in the eastern tropical North Atlantic

    NASA Astrophysics Data System (ADS)

    Loescher, Carolin; Fischer, Martin; Neulinger, Sven; Fiedler, Björn; Philippi, Miriam; Schütte, Florian; Singh, Arvind; Hauss, Helena; Karstensen, Johannes; Körtzinger, Arne; Schmitz, Ruth

    2016-04-01

    The eastern tropical North Atlantic (ETNA) is characterized by a highly productive coastal upwelling system and a moderate oxygen minimum zone with lowest open ocean oxygen (O2) concentrations of approximately 40 μmol kg-1. The recent discovery of re-occurring mesoscale eddies with close to anoxic O2 concentrations (<1 μmol kg-1) located just below the mixed layer has challenged our understanding of O2 distribution and biogeochemical processes in this area. Here, we present the first microbial community study from a deoxygenated anticyclonic modewater eddy in the open waters of the ETNA. In the eddy, we observed significantly lower bacterial diversity compared to surrounding waters, along with a significant community shift. We detected enhanced primary productivity in the surface layer of the eddy indicated by elevated chlorophyll concentrations and carbon uptake rates of up to three times as high as in surrounding waters. Carbon uptake rates below the euphotic zone correlated to the presence of a specific high-light ecotype of Prochlorococcus, which is usually underrepresented in the ETNA. Our data indicate that high primary production in the eddy fuels export production and supports enhanced respiration in a specific microbial community at shallow depths, below the mixed layer base. The O2-depleted core waters eddy promoted transcription of the key gene for denitrification, nirS. This process is usually absent from the open ETNA waters. In light of future projected ocean deoxygenation, our results show that even distinct events of anoxia have the potential to alter microbial community structure with critical impacts on primary productivity and biogeochemical processes of oceanic water bodies.

  7. Hidden biosphere in an oxygen-deficient Atlantic open ocean eddy: future implications of ocean deoxygenation on primary production in the eastern tropical North Atlantic

    NASA Astrophysics Data System (ADS)

    Löscher, C. R.; Fischer, M. A.; Neulinger, S. C.; Fiedler, B.; Philippi, M.; Schütte, F.; Singh, A.; Hauss, H.; Karstensen, J.; Körtzinger, A.; Künzel, S.; Schmitz, R. A.

    2015-08-01

    The eastern tropical North Atlantic (ETNA) is characterized by a highly productive coastal upwelling system and a moderate oxygen minimum zone with lowest open ocean oxygen (O2) concentrations of around 40 μmol kg-1. Only recently, the discovery of re-occurring mesoscale eddies with sometimes close to anoxic O2 concentrations (<1 μmol kg-1) and located just below the mixed layer challenged our understanding of O2 distribution and biogeochemical processes in this area. Here, we present the first metagenomic dataset from a deoxygenated anticyclonic modewater eddy in the open waters of the ETNA. In the eddy, we observed a significantly lower bacterial diversity compared to surrounding waters, along with a significant community shift. We detected enhanced primary productivity in the surface layer of the eddy indicated by elevated chlorophyll concentrations and increased carbon uptake rates up to three times as high as in surrounding waters. Carbon uptake below the euphotic zone correlated to the presence of a specific high-light ecotype of Prochlorococcus, which is usually underrepresented in the ETNA. Our combined data indicate that high primary production in the eddy fuels export production and the presence of a specific microbial community responsible for enhanced respiration at shallow depths, below the mixed layer base. Progressively decreasing O2 concentrations in the eddy were found to promote transcription of the key gene for denitrification, nirS, in the O2-depleted core waters. This process is usually absent from the open ETNA waters. In the light of future ocean deoxygenation our results show exemplarily that even distinct events of anoxia have the potential to alter microbial community structures and with that critically impact primary productivity and biogeochemical processes of oceanic water bodies.

  8. Radiation transport within oceanic (case 1) water

    NASA Astrophysics Data System (ADS)

    Morel, André; Gentili, Bernard

    2004-06-01

    A spectral model of the inherent optical properties (IOP) of oceanic case 1 waters, as previously developed for studying the near-surface bidirectional reflectance, provides the input parameters for the present computations of radiative transport (RT), now extended throughout the water column (three times the euphotic zone). All spectral apparent optical properties (AOP) are computed at each of the levels (30) for six chlorophyll values (from 0.03 to 10 mg m-3) and for six values of the zenith Sun angle (from 0° to 75°). The Raman emission is accounted for. From the irradiances and radiances values the various attenuation coefficients (K), the average cosines (?), and the reflectance (R) are derived for all depths and layers. Their variations resulting from the Sun's position are also studied, which removes the static character of previous empirical models inasmuch as the diurnal changes of the parameters describing the in-water light field can be predicted. The AOPs observed within the deepest levels are also compared to values independently derived from an asymptotic (iterative) solution of the RT. The rate of approach to the asymptotic regime is numerically analyzed; this rate is actually governed by τb, i.e., this fraction of τ (the optical thickness) that corresponds only to scattering. Practical applications of these systematic computations are examined, such as the change (with solar position) of the euphotic depth, the time- and wavelength-dependent scalar irradiance that controls during the day the energy available for photosynthesis (or the heating rate), and the interpretation of radiometric field experiments involving upward and downward irradiance measurements. Some approximate expressions relating AOPs to IOPs are examined in the light of exact computations.

  9. GEOSS interoperability for Weather, Ocean and Water

    NASA Astrophysics Data System (ADS)

    Richardson, David; Nyenhuis, Michael; Zsoter, Ervin; Pappenberger, Florian

    2013-04-01

    "Understanding the Earth system — its weather, climate, oceans, atmosphere, water, land, geodynamics, natural resources, ecosystems, and natural and human-induced hazards — is crucial to enhancing human health, safety and welfare, alleviating human suffering including poverty, protecting the global environment, reducing disaster losses, and achieving sustainable development. Observations of the Earth system constitute critical input for advancing this understanding." With this in mind, the Group on Earth Observations (GEO) started implementing the Global Earth Observation System of Systems (GEOSS). GEOWOW, short for "GEOSS interoperability for Weather, Ocean and Water", is supporting this objective. GEOWOW's main challenge is to improve Earth observation data discovery, accessibility and exploitability, and to evolve GEOSS in terms of interoperability, standardization and functionality. One of the main goals behind the GEOWOW project is to demonstrate the value of the TIGGE archive in interdisciplinary applications, providing a vast amount of useful and easily accessible information to the users through the GEO Common Infrastructure (GCI). GEOWOW aims at developing funcionalities that will allow easy discovery, access and use of TIGGE archive data and of in-situ observations, e.g. from the Global Runoff Data Centre (GRDC), to support applications such as river discharge forecasting.TIGGE (THORPEX Interactive Grand Global Ensemble) is a key component of THORPEX: a World Weather Research Programme to accelerate the improvements in the accuracy of 1-day to 2 week high-impact weather forecasts for the benefit of humanity. The TIGGE archive consists of ensemble weather forecast data from ten global NWP centres, starting from October 2006, which has been made available for scientific research. The TIGGE archive has been used to analyse hydro-meteorological forecasts of flooding in Europe as well as in China. In general the analysis has been favourable in terms of

  10. Airborne Multi-Angle Hyper-Spectral Measurements of White Caps on the Open Ocean

    NASA Astrophysics Data System (ADS)

    Laveigne, J.; Cairns, B.; Diner, D. J.

    2004-05-01

    The influence of whitecaps on the atmospheric correction of ocean color measurements is highly dependent on the spectral variation of albedo that is assumed for the whitecaps. Field measurements of breaking waves in the surf zone indicate a strong spectral variation in whitecap reflectance with the reflectance at 1650 nm nm decreasing by 95% relative to that at 440 nm. The cause of this spectral variation is thought to be the strong absorption by water at longer wavelengths that attenuates light reflected from submerged bubbles. Measurements made during an ocean cruise suggest that the magnitude of this decrease is typically less in the open ocean where the wave breaking is less violent and bubbles are not injected as deep into the water. Nonetheless, even in the open ocean, when whitecaps are large and bright similar decreases in reflectance from 440 nm to 860 nm to those observed in the surf zone are seen. Unfortunately, although measurements in the vicinity of 1600 and 2200 nm are important for remote sensing of aerosols and the atmospheric correction of ocean color measurements, the longest wavelength used for the open ocean measurements was 860 nm. Information about typical reflectance decreases from 440 nm to these longer wavelengths is therefore missing. One approach to remedying this absence of information about the spectral variation of white cap albedo across the solar spectrum is to use an airborne imaging spectrometer. However, a significant difficulty in using airborne, or ship-borne, instrumentation to measure the spectral albedo of whitecaps is the contamination of data by sun glitter. It is usually much more difficult than anticipated to filter data to reject glitter, even for ship-borne measurements with a television camera that provides a visual reference. This means that most data that is reported is obtained under overcast conditions. One approach to alleviating the problems caused by sun glitter is to using multi-angle remote sensing. If

  11. Early opening of initially closed Gulf of Mexico and central North Atlantic ocean

    SciTech Connect

    Van Siclen, D.C.

    1984-09-01

    This paper presents ideas on the early opening and evolution of the Gulf of Mexico and the central North Atlantic ocean. It discusses rifting activity, plate tectonics, magnetic anomalies, and the geologic time elements involved.

  12. Nutrition considerations for open-water swimming.

    PubMed

    Shaw, Gregory; Koivisto, Anu; Gerrard, David; Burke, Louise M

    2014-08-01

    Open-water swimming (OWS) is a rapidly developing discipline. Events of 5-25 km are featured at FINA World Championships, and the international circuit includes races of 5-88 km. The Olympic OWS event, introduced in 2008, is contested over 10 km. Differing venues present changing environmental conditions, including water and ambient temperatures, humidity, solar radiation, and unpredictable tides. Furthermore, the duration of most OWS events (1-6 hr) creates unique physiological challenges to thermoregulation, hydration status, and muscle fuel stores. Current nutrition recommendations for open-water training and competition are either an extension of recommendations from pool swimming or are extrapolated from other athletic populations with similar physiological requirements. Competition nutrition should focus on optimizing prerace hydration and glycogen stores. Although swimmers should rely on self-supplied fuel and fluid sources for shorter events, for races of 10 km or greater, fluid and fuel replacement can occur from feeding pontoons when tactically appropriate. Over the longer races, feeding pontoons should be used to achieve desirable targets of up to 90 g/ hr of carbohydrates from multitransportable sources. Exposure to variable water and ambient temperatures will play a significant role in determining race nutrition strategies. For example, in extreme environments, thermoregulation may be assisted by manipulating the temperature of the ingested fluids. Swimmers are encouraged to work with nutrition experts to develop effective and efficient strategies that enhance performance through appropriate in-competition nutrition.

  13. Diversity and oceanic distribution of prasinophytes clade VII, the dominant group of green algae in oceanic waters.

    PubMed

    Lopes Dos Santos, Adriana; Gourvil, Priscillia; Tragin, Margot; Noël, Mary-Hélène; Decelle, Johan; Romac, Sarah; Vaulot, Daniel

    2017-02-01

    Prasinophytes clade VII is a group of pico/nano-planktonic green algae (division Chlorophyta) for which numerous ribosomal RNA (rRNA) sequences have been retrieved from the marine environment in the last 15 years. A large number of strains have also been isolated but have not yet received a formal taxonomic description. A phylogenetic analysis of available strains using both the nuclear 18S and plastidial 16S rRNA genes demonstrates that this group composes at least 10 different clades: A1-A7 and B1-B3. Analysis of sequences from the variable V9 region of the 18S rRNA gene collected during the Tara Oceans expedition and in the frame of the Ocean Sampling Day consortium reveal that clade VII is the dominant Chlorophyta group in oceanic waters, replacing Mamiellophyceae, which have this role in coastal waters. At some location, prasinophytes clade VII can even be the dominant photosynthetic eukaryote representing up to 80% of photosynthetic metabarcodes overall. B1 and A4 are the overall dominant clades and different clades seem to occupy distinct niches, for example, A6 is dominant in surface Mediterranean Sea waters, whereas A4 extend to high temperate latitudes. Our work demonstrates that prasinophytes clade VII constitute a highly diversified group, which is a key component of phytoplankton in open oceanic waters but has been neglected in the conceptualization of marine microbial diversity and carbon cycle.

  14. A pretty good sponge: Dealing with open boundaries in limited-area ocean models

    NASA Astrophysics Data System (ADS)

    Lavelle, J. W.; Thacker, W. C.

    The problem of computing within a limited domain surrounded by open boundaries is discussed within the context of the shallow-water wave equations by comparing three different treatments, all of which surround the domain by absorbing zones intended to prevent reflections of outgoing waves. The first, which has attracted a lot of attention for use in electromagnetic and aeroacoustic applications, is intended to prevent all reflections. However, it has not yet been developed to handle the second important requirement of open boundaries, namely the ability to pass information about external conditions into the domain of interest. The other two treatments, which absorb differences from a specified external solution, allow information to pass through the open boundary in both directions. One, based on the flow relaxation scheme of [Martinsen, E.A., Engedahl, H., 1987. Implementation and testing of a lateral boundary scheme as an open-boundary condition in a barotropic ocean model. Coastal Eng. 11, 603-627] and termed here the "simple sponge," relaxes all fields toward their external counterparts. The other, a simplification and generalization of the perfectly matched layer, referred to here as the "pretty good sponge," avoids absorbing the component of momentum parallel to the open boundary. Comparisons for a case that is dominated by outgoing waves shows the pretty good sponge to perform essentially as well as the perfectly matched layer and better than the simple sponge. In comparisons for a geostrophically balanced eddy passing through open boundaries, the pretty good sponge out-performed the simple sponge when the only external information available was about the advecting flow, but when information about the nature of the eddy in the sponge zones was also available, the simple sponge performed better. For the case of an equatorial soliton passing through the boundary and no information provided about its nature outside the open domain, again the pretty good sponge

  15. An open source simulator for water management

    NASA Astrophysics Data System (ADS)

    Knox, Stephen; Meier, Philipp; Selby, Philip; Mohammed, Khaled; Khadem, Majed; Padula, Silvia; Harou, Julien; Rosenberg, David; Rheinheimer, David

    2015-04-01

    Descriptive modelling of water resource systems requires the representation of different aspects in one model: the physical system including hydrological inputs and engineered infrastructure, and human management, including social, economic and institutional behaviours and constraints. Although most water resource systems share some characteristics such as the ability to represent them as a network of nodes and links, geographical, institutional and other differences mean that invariably each water system functions in a unique way. A diverse group is developing an open source simulation framework which will allow model developers to build generalised water management models that are customised to the institutional, physical and economical components they are seeking to model. The framework will allow the simulation of complex individual and institutional behaviour required for the assessment of real-world resource systems. It supports the spatial and hierarchical structures commonly found in water resource systems. The individual infrastructures can be operated by different actors while policies are defined at a regional level by one or more institutional actors. The framework enables building multi-agent system simulators in which developers can define their own agent types and add their own decision making code. Developers using the framework have two main tasks: (i) Extend the core classes to represent the aspects of their particular system, and (ii) write model structure files. Both are done in Python. For task one, users must either write new decision making code for each class or link to an existing code base to provide functionality to each of these extension classes. The model structure file links these extension classes in a standardised way to the network topology. The framework will be open-source and written in Python and is to be available directly for download through standard installer packages. Many water management model developers are unfamiliar

  16. Small-scale open ocean currents have large effects on wind wave heights

    NASA Astrophysics Data System (ADS)

    Ardhuin, Fabrice; Gille, Sarah T.; Menemenlis, Dimitris; Rocha, Cesar B.; Rascle, Nicolas; Chapron, Bertrand; Gula, Jonathan; Molemaker, Jeroen

    2017-06-01

    Tidal currents and large-scale oceanic currents are known to modify ocean wave properties, causing extreme sea states that are a hazard to navigation. Recent advances in the understanding and modeling capability of open ocean currents have revealed the ubiquitous presence of eddies, fronts, and filaments at scales 10-100 km. Based on realistic numerical models, we show that these structures can be the main source of variability in significant wave heights at scales less than 200 km, including important variations down to 10 km. Model results are consistent with wave height variations along satellite altimeter tracks, resolved at scales larger than 50 km. The spectrum of significant wave heights is found to be of the order of 70>>2/>(g2>>2>) times the current spectrum, where >> is the spatially averaged significant wave height, >> is the energy-averaged period, and g is the gravity acceleration. This variability induced by currents has been largely overlooked in spite of its relevance for extreme wave heights and remote sensing.Plain Language SummaryWe show that the variations in currents at scales 10 to 100 km are the main source of variations in wave heights at the same scales. Our work uses a combination of realistic numerical models for currents and waves and data from the Jason-3 and SARAL/AltiKa satellites. This finding will be of interest for the investigation of extreme wave heights, remote sensing, and air-sea interactions. As an immediate application, the present results will help constrain the error budget of the up-coming satellite missions, in particular the Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) mission, and decide how the data will have to be processed to arrive at accurate sea level and wave measurements. It will also help in the analysis of wave measurements by the CFOSAT satellite.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.epa.gov/ocean-dumping/southeast-regional-implementation-manual-requirements-and-procedures-evaluation-ocean','PESTICIDES'); return false;" href="https://www.epa.gov/ocean-dumping/southeast-regional-implementation-manual-requirements-and-procedures-evaluation-ocean"><span>Southeast Regional Implementation Manual for Requirements and Procedures for Evaluation of the <span class="hlt">Ocean</span> Disposal of Dredged Material in Southeastern U.S. Atlantic and Gulf Coast <span class="hlt">Waters</span></span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>This Regional Implementation Manual was prepared by EPA Region 4 to provide guidance for applicants proposing <span class="hlt">open-water</span> disposal of dredged material in southeastern U.S. coastal <span class="hlt">waters</span> of the Atlantic <span class="hlt">Ocean</span> and the Gulf of Mexico.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010EGUGA..1211465L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010EGUGA..1211465L"><span>The EuroSITES network: Integrating and enhancing fixed-point <span class="hlt">open</span> <span class="hlt">ocean</span> observatories around Europe</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lampitt, Richard S.; Larkin, Kate E.; EuroSITES Consortium</p> <p>2010-05-01</p> <p>EuroSITES is a 3 year (2008-2011) EU collaborative project (3.5MEuro) with the objective to integrate and enhance the nine existing <span class="hlt">open</span> <span class="hlt">ocean</span> fixed point observatories around Europe (www.eurosites.info). These observatories are primarily composed of full depth moorings and make multidisciplinary in situ observations within the <span class="hlt">water</span> column as the European contribution to the global array <span class="hlt">Ocean</span>SITES (www.oceansites.org). In the first 18 months, all 9 observatories have been active and integration has been significant through the maintenance and enhancement of observatory hardware. Highlights include the enhancement of observatories with sensors to measure O2, pCO2, chlorophyll, and nitrate in near real-time from the upper 1000 m. In addition, some seafloor missions are also actively supported. These include seafloor platforms currently deployed in the Mediterranean, one for tsunami detection and one to monitor fluid flow related to seismic activity and slope stability. Upcoming seafloor science missions in 2010 include monitoring benthic biological communities and associated biogeochemistry as indicators of climate change in both the Northeast Atlantic and Mediterranean. EuroSITES also promotes the development of innovative sensors and samplers in order to progress capability to measure climate-relevant properties of the <span class="hlt">ocean</span>. These include further developing current technologies for autonomous long-term monitoring of oxygen consumption in the mesopelagic, pH and mesozooplankton abundance. Many of these science missions are directly related to complementary activities in other European projects such as EPOCA, HYPOX and ESONET. In 2010 a direct collaboration including in situ field work will take place between ESONET and EuroSITES. The demonstration mission MODOO (funded by ESONET) will be implemented in 2010 at the EuroSITES PAP observatory. Field work will include deployment of a seafloor lander system with various sensors which will send data to shore in real</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000013567&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000013567&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wright, C. W.; Walsh, E. J.; Vandemark, D.; Krabill, W. B.; Garcia, A. W.</p> <p>1999-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane hunter aircraft at 1.5 km height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. At 8 Hz, the SRA sweeps a radar beam of 1 deg half-power width (two-way) across the aircraft ground track over a swath equal to 0. 8 of the aircraft height, simultaneously measuring the backscattered power at its 36 GHz (8.3 mm) operating frequency and the range to the sea surface at 64 positions. These slant ranges are multiplied by the cosine of the incidence angles to determine the vertical distances from the aircraft to the sea surface. Subtracting these distances from the aircraft height produces the sea surface elevation map. The sea surface topography is interpolated to a uniform grid, transformed by a two-dimensional FFT, and Doppler corrected. The data presented were acquired on 24 August 1998 when hurricane Bonnie was east of the Bahamas and moving slowly to the north. Wave heights up to 18 m were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction and at times there were wave fields traveling at right angles to each other. The NOAA aircraft spent over five hours within 180 km of the hurricane Bonnie eye, and made five eye penetrations. A 2-minute animation of the directional wave spectrum spatial variation over this period will be shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1810692V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1810692V"><span><span class="hlt">Ocean</span> <span class="hlt">water</span> cycle: its recent amplification and impact on <span class="hlt">ocean</span> circulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vinogradova, Nadya</p> <p>2016-04-01</p> <p><span class="hlt">Oceans</span> are the largest reservoir of the world's <span class="hlt">water</span> supply, accounting for 97% of the Earth's <span class="hlt">water</span> and supplying more than 75% of the evaporated and precipitated <span class="hlt">water</span> in the global <span class="hlt">water</span> cycle. Therefore, in order to predict the future of the global hydrological cycle, it is essential to understand the changes in its largest component, which is the flux of freshwater over the <span class="hlt">oceans</span>. Here we examine the change in the <span class="hlt">ocean</span> <span class="hlt">water</span> cycle and the <span class="hlt">ocean</span>'s response to such changes that were happening during the last two decades. The analysis is based on a data-constrained <span class="hlt">ocean</span> state estimate that synthesizes all of the information available in the surface fluxes, winds, observations of sea level, temperature, salinity, geoid, etc., as well as in the physical constraints, dynamics, and conservation statements that are embedded in the equations of the MIT general circulation model. Closeness to observations and dynamical consistency of the solution ensures a physically realistic correspondence between the atmospheric forcing and <span class="hlt">oceanic</span> fluxes, including the <span class="hlt">ocean</span>'s response to freshwater input. The results show a robust pattern of change in the <span class="hlt">ocean</span> <span class="hlt">water</span> cycle in the last twenty years. The pattern of changes indicates a general tendency of drying of the subtropics, and wetting in the tropics and mid-to-high latitudes, following the "rich get richer and the poor get poorer" paradigm in many <span class="hlt">ocean</span> regions. Using a closed property budget analysis, we then investigate the changes in the <span class="hlt">oceanic</span> state (salinity, temperature, sea level) during the same twenty-year period. The results are discussed in terms of the origin of surface signatures, and differentiated between those that are attributed to short-term natural variability and those that result from an intensified hydrological cycle due to warming climate.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_6");'>6</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li class="active"><span>8</span></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_8 --> <div id="page_9" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="161"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1983STIN...8323852G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1983STIN...8323852G"><span>Study of hydraulic air compression for <span class="hlt">Ocean</span> Thermal Energy Conversion <span class="hlt">open</span>-cycle application</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Golshani, A.; Chen, F. C.</p> <p>1983-01-01</p> <p>A hydraulic air compressor, which requires no mechanical moving parts and operates in a nearly isothermal mode, can be an alternative for the noncondensible gas disposal of an <span class="hlt">Ocean</span> Thermal Energy Conversion (OTEC) <span class="hlt">open</span>-cycle power system. The compressor requires only a downward flow of <span class="hlt">water</span> to accomplish air compression. An air compressor test loop was assembled and operated to obtain test data that would lead to the design of an OTEC hydraulic air compressor. A one dimensional, hydraulic gas compressor, computer model was employed to simulate the laboratory experiments, and it was tuned to fit the test results. A sensitivity study that shows the effects of various parameters on the applied head of the hydraulic air compression is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20020022890&hterms=Hurricane+Size&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BSize','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20020022890&hterms=Hurricane+Size&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BSize"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span> and at Landfall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walsh, E. J.; Wright, C. W.; Vandemark, D.; Krabill, W. B.; Garcia, A. W.; Houston, S. H.; Murillo, S. T.; Powell, M. D.; Black, P. G.; Marks, F. D.; <a style="text-decoration: none; " href="javascript:void(0); " onClick="displayelement('author_20020022890'); toggleEditAbsImage('author_20020022890_show'); toggleEditAbsImage('author_20020022890_hide'); "> <img style="display:inline; width:12px; height:12px; " src="images/arrow-up.gif" width="12" height="12" border="0" alt="hide" id="author_20020022890_show"> <img style="width:12px; height:12px; display:none; " src="images/arrow-down.gif" width="12" height="12" border="0" alt="hide" id="author_20020022890_hide"></p> <p>2001-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane research aircraft at 1.5 kilometer height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. The data were acquired on 24 August 1998 when Hurricane Bonnie was 400 km east of Abaco Island, Bahamas. Individual waves with heights up to 19 meters were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At one position, three different wave systems of comparable energy and wavelength crossed each other. The aircraft spent over five hours within 180 kilometers of the Hurricane Bonnie eye and made five eye penetrations. On 26 August 1998, the SRA at 2.2 kilometer height documented the directional wave spectrum in the region between Charleston, SC, and Cape Hatteras, NC, as Hurricane Bonnie was making landfall near Wilmington, NC. The storm was similar in size during the two flights, but the maximum speed in the NOAA Hurricane Research Division surface wind analysis was 15% lower prior to landfall (39 meters per second) than it had been in the <span class="hlt">open</span> <span class="hlt">ocean</span> (46 meters per second). This was compensated for by its faster movement prior to landfall (9.5 meters per second) than when it was encountered in the <span class="hlt">open</span> <span class="hlt">ocean</span> (5 meters per second), significantly increasing the effective fetch and duration of waves near the peak of the spectrum which propagated in the direction of the storm track. The <span class="hlt">open</span> <span class="hlt">ocean</span> wave height variation indicated that Hurricane Bonnie would have produced waves of 11 meters significant wave height on the shore northeast of Wilmington had it not been for the continental shelf. The bathymetry distributed the steepening and breaking process across the shelf so that the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19850017722&hterms=many+oceans+world&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmany%2Boceans%2Bworld','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19850017722&hterms=many+oceans+world&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmany%2Boceans%2Bworld"><span>North Atlantic Deep <span class="hlt">Water</span> and the World <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gordon, A. L.</p> <p>1984-01-01</p> <p>North Atlantic Deep <span class="hlt">Water</span> (NADW) by being warmer and more saline than the average abyssal <span class="hlt">water</span> parcel introduces heat and salt into the abyssal <span class="hlt">ocean</span>. The source of these properties is upper layer or thermocline <span class="hlt">water</span> considered to occupy the <span class="hlt">ocean</span> less dense than sigma-theta of 27.6. That NADW convects even though it's warmer than the abyssal <span class="hlt">ocean</span> is obviously due to the high salinity. In this way, NADW formation may be viewed as saline convection. The counter force removing heat and salinity (or introducing fresh <span class="hlt">water</span>) is usually considered to to take place in the Southern <span class="hlt">Ocean</span> where upwelling deep <span class="hlt">water</span> is converted to cold fresher Antarctic <span class="hlt">water</span> masses. The Southern <span class="hlt">ocean</span> convective process is driven by low temperatures and hence may be considered as thermal convection. A significant fresh <span class="hlt">water</span> source may also occur in the North Pacific where the northward flowing of abyssal <span class="hlt">water</span> from the Southern circumpolar belt is saltier and denser than the southward flowing, return abyssal <span class="hlt">water</span>. The source of the low salinity input may be vertical mixing of the low salinity surface <span class="hlt">water</span> or the low salinity intermediate <span class="hlt">water</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMOS22E..11V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMOS22E..11V"><span>Did an <span class="hlt">Open</span> Panama Isthmus Correspond to an Invasion of Pacific <span class="hlt">Water</span> into the Atlantic?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vangorder, S.; Nof, D.</p> <p>2002-12-01</p> <p>Existing general circulation modeling studies suggest that, prior to the closure of the Panama isthmus, low salinity Pacific <span class="hlt">ocean</span> <span class="hlt">water</span> invaded the Atlantic <span class="hlt">ocean</span> via the associated gap between North and South America. According to this scenario, the invasion decreased the Atlantic <span class="hlt">Ocean</span> salinity to the point where deep <span class="hlt">water</span> formation was impossible and, consequently, no "conveyer belt" movement was in action. Using simple dynamical principles, analytical modeling and process-oriented numerical experiments, it is shown that one would normally expect a flow from the Atlantic to the Pacific <span class="hlt">Ocean</span> (rather than from the Pacific to the Atlantic) through an <span class="hlt">open</span> Panama isthmus. An analogous present-day situation is that of the Indonesian Throughflow which brings Pacific <span class="hlt">water</span> to the Indian <span class="hlt">Ocean</span> rather than the other way around. The direction of the flow in both situations is determined by the wind field to the east of the gaps. On this basis it is suggested that if low salinity Pacific <span class="hlt">water</span> did in fact invade the Atlantic <span class="hlt">Ocean</span> prior to the closure of the Panama isthmus, then this invasion took place via the Bering Strait rather than through the <span class="hlt">open</span> Panama Isthmus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003EAEJA.....1111V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003EAEJA.....1111V"><span>Did an <span class="hlt">open</span> Panama Isthmus correspond to an invasion of Pacific <span class="hlt">water</span> into the Atlantic?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>van Gorder, S.; Nof, D.</p> <p>2003-04-01</p> <p>Existing general circulation modeling studies suggest that, prior to the closure of the Panama Isthmus, low salinity Pacific <span class="hlt">ocean</span> <span class="hlt">water</span> invaded the Atlantic <span class="hlt">ocean</span> via the associated gap between North and South America. According to this scenario, the invasion decreased the Atlantic <span class="hlt">Ocean</span> salinity to the point where deep <span class="hlt">water</span> formation was impossible and, consequently, no "conveyer belt" movement was in action. Using simple dynamical principles, analytical modeling and process-oriented numerical experiments, it is shown that one would normally expect a flow from the Atlantic to the Pacific <span class="hlt">Ocean</span> (rather than from the Pacific to the Atlantic) through an <span class="hlt">open</span> Panama isthmus. An analogous present-day situation is that of the Indonesian Throughflow which brings Pacific <span class="hlt">water</span> to the Indian <span class="hlt">Ocean</span> rather than the other way around. The direction of the flow in both situations is determined by the wind field to the east of the gaps. On this basis it is suggested that if low salinity Pacific <span class="hlt">water</span> did in fact invade the Atlantic <span class="hlt">Ocean</span> prior to the closure of the Panama isthmus, then this invasion took place via the Bering Strait rather than through the <span class="hlt">open</span> Panama Isthmus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012EGUGA..14.7007P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012EGUGA..14.7007P"><span>Dim <span class="hlt">waters</span>: side effects of geoengineering using <span class="hlt">ocean</span> albedo modification</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Piskozub, J.; Neumann, T.</p> <p>2012-04-01</p> <p>We use a Monte Carlo radiative transfer code to check how the recently proposed geoengineering by injection of clean or coated microbubbles into the <span class="hlt">ocean</span> mixed layer would impact in-<span class="hlt">water</span> light fields. We show that due to massive multiscattering inside a bubble cloud, coating the bubbles with surfactant, needed to stabilize them, would not increase their albedo change effectiveness as much as expected basing on their backscattering coefficients. However, the bubble effect on reflectance is larger than estimated previously using a discrete ordinate method of solving the radiative transfer problem. We show significant side effects of <span class="hlt">ocean</span> albedo change needed to counter global warming expected in this century and beyond (reduction of euphotic zone depth by respectively 20% and 50% in the case of global <span class="hlt">ocean</span> albedo change corresponding to -1.25 K and -6 K global surface temperature change and irradiance decrease at 10 m depth by respectively 40% and over 80%) even if all <span class="hlt">ocean</span> surface was "brightened". We discuss the possible negative side effect of such in-<span class="hlt">water</span> light dimming on marine life. We conclude that the proposed "<span class="hlt">ocean</span> brightening" is in fact "<span class="hlt">ocean</span> dimming" as concerns the marine environment, on a scale that in any other circumstances would be called catastrophic. Finally, we briefly discuss other possible side effect of making the surface <span class="hlt">ocean</span> <span class="hlt">waters</span> turbid (both optically and acoustically), of adding large amounts of surfactants to the surface <span class="hlt">ocean</span> layers and of surface cooling of the <span class="hlt">ocean</span>, especially within the tropics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7046619','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7046619"><span>Experiments on oxygen desorption from surface warm seawater under <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pesaran, A.A. )</p> <p>1992-11-01</p> <p>This paper presents the results of scoping deaeration experiments conducted with warm surface seawater under <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) conditions. Concentrations of dissolved oxygen in seawater at three locations (in the supply <span class="hlt">water</span>, <span class="hlt">water</span> leaving the predeaerator, and discharge <span class="hlt">water</span> from an evaporator) were measured and used to estimate oxygen desorption levels. The results suggest that 7 percent to 60 percent of the dissolved oxygen in the supply <span class="hlt">water</span> was desorbed from seawater in the predeaerator for pressures ranging from 35 to 9 kPa. Bubble injection in the upcomer increased the oxygen desorption rate by 20 percent to 60 percent. The data also indicated that at typical OC-OTEC evaporator pressures, when flash evaporation in the evaporator occurred, 75 percent to 95 percent of the dissolved oxygen was desorbed overall from the warm seawater. The results were used to find the impact of a single-stage predeaeration scheme on the power to remove noncondensable gases in an OC-OTEC plant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ERL.....8a4009K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ERL.....8a4009K"><span>Geoengineering impact of <span class="hlt">open</span> <span class="hlt">ocean</span> dissolution of olivine on atmospheric CO2, surface <span class="hlt">ocean</span> pH and marine biology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Köhler, Peter; Abrams, Jesse F.; Völker, Christoph; Hauck, Judith; Wolf-Gladrow, Dieter A.</p> <p>2013-03-01</p> <p>Ongoing global warming induced by anthropogenic emissions has <span class="hlt">opened</span> the debate as to whether geoengineering is a ‘quick fix’ option. Here we analyse the intended and unintended effects of one specific geoengineering approach, which is enhanced weathering via the <span class="hlt">open</span> <span class="hlt">ocean</span> dissolution of the silicate-containing mineral olivine. This approach would not only reduce atmospheric CO2 and oppose surface <span class="hlt">ocean</span> acidification, but would also impact on marine biology. If dissolved in the surface <span class="hlt">ocean</span>, olivine sequesters 0.28 g carbon per g of olivine dissolved, similar to land-based enhanced weathering. Silicic acid input, a byproduct of the olivine dissolution, alters marine biology because silicate is in certain areas the limiting nutrient for diatoms. As a consequence, our model predicts a shift in phytoplankton species composition towards diatoms, altering the biological carbon pumps. Enhanced olivine dissolution, both on land and in the <span class="hlt">ocean</span>, therefore needs to be considered as <span class="hlt">ocean</span> fertilization. From dissolution kinetics we calculate that only olivine particles with a grain size of the order of 1 μm sink slowly enough to enable a nearly complete dissolution. The energy consumption for grinding to this small size might reduce the carbon sequestration efficiency by ˜30%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO44A3120B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO44A3120B"><span>Tracing the Sinking of Dense <span class="hlt">Ocean</span> <span class="hlt">Waters</span> in the North Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Brueggemann, N.; Katsman, C. A.; Dijkstra, H.</p> <p>2016-02-01</p> <p>In this study, we investigate the sinking of dense <span class="hlt">water</span> masses in the North Atlantic. Therefore, we use data from an eddy permitting (0.1o) <span class="hlt">ocean</span> model of the Parallel <span class="hlt">Ocean</span> Program (POP). Velocity fields of the model are used to advect Lagrangian floats with the Connectivity Modelling System (CMS). Model and float data are used to identify regions where <span class="hlt">water</span> masses sink into the deep <span class="hlt">ocean</span>. Theoretical considerations predict that <span class="hlt">water</span> masses can only sink if the geostrophic balance is broken. We identify mechanisms that are responsible for the ageostrophic dynamics and compare our findings with frequently discussed theories. Since eddies seem to play a dominant role for the deep <span class="hlt">water</span> sinking, it is questionable to which extent coarser resolved <span class="hlt">ocean</span> models that do not resolve the eddies are able to capture the deep <span class="hlt">water</span> sinking. Especially, we aim to clarify if the sinking in a coarser resolved counterpart of the POP <span class="hlt">ocean</span> model (1o) is due to different mechanisms compared to its eddy permitting (0.1o) counterpart. By this, we aim at understanding how the deep sinking of <span class="hlt">water</span> masses as one part of the Meridional Overturning Circulation is represented in typically coarser resolved climate models and how realistic these processes are represented in comparison to higher resolved <span class="hlt">ocean</span> models.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1993PrOce..32..185S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1993PrOce..32..185S"><span>Abundance, variability, and potential grazing impact of planktonic ciliates in the <span class="hlt">open</span> subaratic Pacific <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Strom, Suzanne L.; Postel, James R.; Booth, Beatrice C.</p> <p></p> <p>The abundance and variability of planktonic ciliates in the <span class="hlt">open</span> subarctic Pacific were determined during four month-long cruises in 1987 and 1988. The ciliate community, numerically dominated by relatively small aloricate choreotrichs, was comparable in abundance to communities in a range of <span class="hlt">oceanic</span> and neritic environments, including <span class="hlt">waters</span> with much higher average chlorophyll concentrations. Integrated (0-80m) ciliate biomass was typically 100-200mgC m -2, although 3- to 4-fold higher levels were observed on two occasions in spring. Ciliate community biomass, in general, was dominated by large (>20 μm width) individuals, although in August 1988 the biomass of smaller cells was as great or greater. The estimated grazing impact of the ciliate community averaged 20% of the primary production. On one instance in May 1988, however, a large biomass of ciliates led to an estimated grazing impact equivalent to 55% of phytoplankton production. While ciliates may be major phytoplankton grazers during sporadic ciliate “blooms”, dino- and other heterotrophic flagellates, which make up the bulk of microheterotroph biomass, must normally be of equal or greater importance as herbivores in this <span class="hlt">ocean</span> region.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23038316','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23038316"><span>Particle backscattering as a function of chlorophyll and phytoplankton size structure in the <span class="hlt">open-ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brewin, Robert J W; Dall'Olmo, Giorgio; Sathyendranath, Shubha; Hardman-Mountford, Nick J</p> <p>2012-07-30</p> <p>Using an extensive database of in situ observations we present a model that estimates the particle backscattering coefficient as a function of the total chlorophyll concentration in the <span class="hlt">open-ocean</span> (Case-1 <span class="hlt">waters</span>). The parameters of the model include a constant background component and the chlorophyll-specific backscattering coefficients associated with small (<20 μm) and large (>20 μm) phytoplankton. The new model performed with similar accuracy when compared with a traditional power-law function, with the additional benefit of providing information on the role of phytoplankton size. The observed spectral-dependency (γ) of model parameters was consistent with past observations, such that γ associated with the small phytoplankton population was higher than that of large phytoplankton. Furthermore, γ associated with the constant background component suggests this component is likely attributed to submicron particles. We envisage that the model would be useful for improving Case-1 <span class="hlt">ocean</span>-colour models, assimilating light into multi-phytoplankton ecosystem models and improving estimates of phytoplankton size structure from remote sensing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=334670&keyword=Ocean&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=334670&keyword=Ocean&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Modeling <span class="hlt">Water</span> Clarity and Light Quality in <span class="hlt">Oceans</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Phytoplankton is a primary producer of organic compounds, and it forms the base of the food chain in <span class="hlt">ocean</span> <span class="hlt">waters</span>. The concentration of phytoplankton in the <span class="hlt">water</span> column controls <span class="hlt">water</span> clarity and the amount and quality of light that penetrates through it. The availability of ade...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=334670&keyword=Food+AND+chain&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91085285&CFTOKEN=42300748','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=334670&keyword=Food+AND+chain&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=91085285&CFTOKEN=42300748"><span>Modeling <span class="hlt">Water</span> Clarity and Light Quality in <span class="hlt">Oceans</span></span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Phytoplankton is a primary producer of organic compounds, and it forms the base of the food chain in <span class="hlt">ocean</span> <span class="hlt">waters</span>. The concentration of phytoplankton in the <span class="hlt">water</span> column controls <span class="hlt">water</span> clarity and the amount and quality of light that penetrates through it. The availability of ade...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19137950','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19137950"><span>Large-scale diversity patterns of cephalopods in the Atlantic <span class="hlt">open</span> <span class="hlt">ocean</span> and deep sea.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rosa, Rui; Dierssen, Heidi M; Gonzalez, Liliana; Seibel, Brad A</p> <p>2008-12-01</p> <p>Although the <span class="hlt">oceans</span> cover 70% of the Earth's surface and the <span class="hlt">open</span> <span class="hlt">ocean</span> is by far the largest ecosystem on the planet, our knowledge regarding diversity patterns of pelagic fauna is very scarce. Here, we examine large-scale latitudinal and depth-related patterns of pelagic cephalopod richness in the Atlantic <span class="hlt">Ocean</span> in relation to ambient thermal and productive energy availability. Diversity, across 17 biogeochemical regions in the <span class="hlt">open</span> <span class="hlt">ocean</span>, does not decline monotonically with latitude, but is positively correlated to the availability of <span class="hlt">oceanic</span> resources. Mean net primary productivity (NPP), determined from <span class="hlt">ocean</span> color satellite imagery, explains 37% of the variance in species richness. Outside the poles, the range in NPP explains over 40% of the variability. This suggests that cephalopods are well adapted to the spatial patchiness and seasonality of <span class="hlt">open-ocean</span> resources. Pelagic richness is also correlated to sea surface temperature, with maximum richness occurring around 15 degrees C and decreasing with both colder and warmer temperatures. Both pelagic and benthos-associated diversities decline sharply from sublittoral and epipelagic regions to the slope and bathypelagic habitats and then steadily to abyssal depths. Thus, higher energy availability at shallow depths seems to promote diversification rates. This strong depth-related trend in diversity also emphasizes the greater influence of the sharp vertical thermal gradient than the smoother and more seasonal horizontal (latitudinal) one on marine diversity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014BGD....1117391K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014BGD....1117391K"><span><span class="hlt">Open</span> <span class="hlt">ocean</span> dead-zone in the tropical North Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karstensen, J.; Fiedler, B.; Schütte, F.; Brandt, P.; Körtzinger, A.; Fischer, G.; Zantopp, R.; Hahn, J.; Visbeck, M.; Wallace, D.</p> <p>2014-12-01</p> <p>The intermittent appearances of low oxygen environments are a particular thread for marine ecosystems. Here we present first observations of unexpected low (<2 μmol kg-1) oxygen environments in the <span class="hlt">open</span> <span class="hlt">waters</span> of the eastern tropical North Atlantic, a region where typically oxygen concentration does not fall below 40 μmol kg-1. The low oxygen zones are created just below the mixed-layer, in the euphotic zone of high productive cyclonic and anticyclonic-modewater eddies. A dynamic boundary is created from the large swirl-velocity against the weak background flow. Hydrographic properties within the eddies are kept constant over periods of several months, while net respiration is elevated by a factor of 3 to 5 reducing the oxygen content. We repeatedly observed low oxygen eddies in the region. The direct impact on the ecosystem is evident from anomalous backscatter behaviour. Satellite derived global eddy statistics do not allow to estimate the large-scale impact of the eddies because their vertical structure (mixed-layer depth, euphotic depth) play a key role in creating the low oxygen environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.A43A0259S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.A43A0259S"><span>Sensitivity of the remote sensing reflectance of <span class="hlt">ocean</span> and coastal <span class="hlt">waters</span> to uncertainties in aerosol characteristics</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Seidel, F. C.; Garay, M. J.; Zhai, P.; Kalashnikova, O. V.; Diner, D. J.</p> <p>2015-12-01</p> <p>Remote sensing is a powerful tool for optical oceanography and limnology to monitor and study <span class="hlt">ocean</span>, coastal, and inland <span class="hlt">water</span> ecosystems. However, the highly spatially and temporally variable nature of <span class="hlt">water</span> conditions and constituents, as well as atmospheric conditions are challenging factors, especially for spaceborne observations.Here, we study the quantitative impact of uncertainties in the spectral aerosol optical and microphysical properties, namely aerosol optical depth (AOD), spectral absorption, and particle size, on the remote sensing reflectance (Rrs) of simulated typical <span class="hlt">open</span> <span class="hlt">ocean</span> and coastal <span class="hlt">waters</span>. Rrs is related to the inherent optical properties of the <span class="hlt">water</span> column and is a fundamental parameter in <span class="hlt">ocean</span> optics retrievals. We use the successive order of scattering (SOS) method to perform radiative transfer calculations of the coupled system of atmosphere and <span class="hlt">water</span>. The optics of typical <span class="hlt">open</span> <span class="hlt">ocean</span> and coastal <span class="hlt">waters</span> are simulated with bio-optical models. We derive sensitivities by comparing spectral SOS calculations of Rrs with a reference aerosol model against similar calculations performed using a different aerosol model. One particular focus of this study lies on the impact of the spectral absorption of dust and brown carbon, or similar particles with greater absorption at short wavelengths on Rrs. The results are presented in terms of the minimum expected error in Rrs due to the choice of an incorrect aerosol model during the atmospheric correction of <span class="hlt">ocean</span> color remote sensing data from space. This study is independent of errors related to observational data or retrieval techniques.The results are relevant for quantifying requirements of aerosol retrievals to derive accurate Rrs from spaceborne observations, such as NASA's future Pre-Aerosol, Clouds, and <span class="hlt">ocean</span> Ecosystem (PACE) mission.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26029378','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26029378"><span><span class="hlt">Open</span> science resources for the discovery and analysis of Tara <span class="hlt">Oceans</span> data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pesant, Stéphane; Not, Fabrice; Picheral, Marc; Kandels-Lewis, Stefanie; Le Bescot, Noan; Gorsky, Gabriel; Iudicone, Daniele; Karsenti, Eric; Speich, Sabrina; Troublé, Romain; Dimier, Céline; Searson, Sarah</p> <p>2015-01-01</p> <p>The Tara <span class="hlt">Oceans</span> expedition (2009-2013) sampled contrasting ecosystems of the world <span class="hlt">oceans</span>, collecting environmental data and plankton, from viruses to metazoans, for later analysis using modern sequencing and state-of-the-art imaging technologies. It surveyed 210 ecosystems in 20 biogeographic provinces, collecting over 35,000 samples of seawater and plankton. The interpretation of such an extensive collection of samples in their ecological context requires means to explore, assess and access raw and validated data sets. To address this challenge, the Tara <span class="hlt">Oceans</span> Consortium offers <span class="hlt">open</span> science resources, including the use of <span class="hlt">open</span> access archives for nucleotides (ENA) and for environmental, biogeochemical, taxonomic and morphological data (PANGAEA), and the development of on line discovery tools and collaborative annotation tools for sequences and images. Here, we present an overview of Tara <span class="hlt">Oceans</span> Data, and we provide detailed registries (data sets) of all campaigns (from port-to-port), stations and sampling events.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4443879','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4443879"><span><span class="hlt">Open</span> science resources for the discovery and analysis of Tara <span class="hlt">Oceans</span> data</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Pesant, Stéphane; Not, Fabrice; Picheral, Marc; Kandels-Lewis, Stefanie; Le Bescot, Noan; Gorsky, Gabriel; Iudicone, Daniele; Karsenti, Eric; Speich, Sabrina; Troublé, Romain; Dimier, Céline; Searson, Sarah; Acinas, Silvia G.; Bork, Peer; Boss, Emmanuel; Bowler, Chris; Vargas, Colomban De; Follows, Michael; Gorsky, Gabriel; Grimsley, Nigel; Hingamp, Pascal; Iudicone, Daniele; Jaillon, Olivier; Kandels-Lewis, Stefanie; Karp-Boss, Lee; Karsenti, Eric; Krzic, Uros; Not, Fabrice; Ogata, Hiroyuki; Pesant, Stéphane; Raes, Jeroen; Reynaud, Emmanuel G.; Sardet, Christian; Sieracki, Mike; Speich, Sabrina; Stemmann, Lars; Sullivan, Matthew B.; Sunagawa, Shinichi; Velayoudon, Didier; Weissenbach, Jean; Wincker, Patrick</p> <p>2015-01-01</p> <p>The Tara <span class="hlt">Oceans</span> expedition (2009–2013) sampled contrasting ecosystems of the world <span class="hlt">oceans</span>, collecting environmental data and plankton, from viruses to metazoans, for later analysis using modern sequencing and state-of-the-art imaging technologies. It surveyed 210 ecosystems in 20 biogeographic provinces, collecting over 35,000 samples of seawater and plankton. The interpretation of such an extensive collection of samples in their ecological context requires means to explore, assess and access raw and validated data sets. To address this challenge, the Tara <span class="hlt">Oceans</span> Consortium offers <span class="hlt">open</span> science resources, including the use of <span class="hlt">open</span> access archives for nucleotides (ENA) and for environmental, biogeochemical, taxonomic and morphological data (PANGAEA), and the development of on line discovery tools and collaborative annotation tools for sequences and images. Here, we present an overview of Tara <span class="hlt">Oceans</span> Data, and we provide detailed registries (data sets) of all campaigns (from port-to-port), stations and sampling events. PMID:26029378</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040047277','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040047277"><span>Fresh <span class="hlt">Water</span> Content Variability in the Arctic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hakkinen, Sirpa; Proshutinsky, Andrey</p> <p>2003-01-01</p> <p>Arctic <span class="hlt">Ocean</span> model simulations have revealed that the Arctic <span class="hlt">Ocean</span> has a basin wide oscillation with cyclonic and anticyclonic circulation anomalies (Arctic <span class="hlt">Ocean</span> Oscillation; AOO) which has a prominent decadal variability. This study explores how the simulated AOO affects the Arctic <span class="hlt">Ocean</span> stratification and its relationship to the sea ice cover variations. The simulation uses the Princeton <span class="hlt">Ocean</span> Model coupled to sea ice. The surface forcing is based on NCEP-NCAR Reanalysis and its climatology, of which the latter is used to force the model spin-up phase. Our focus is to investigate the competition between <span class="hlt">ocean</span> dynamics and ice formation/melt on the Arctic basin-wide fresh <span class="hlt">water</span> balance. We find that changes in the Atlantic <span class="hlt">water</span> inflow can explain almost all of the simulated fresh <span class="hlt">water</span> anomalies in the main Arctic basin. The Atlantic <span class="hlt">water</span> inflow anomalies are an essential part of AOO, which is the wind driven barotropic response to the Arctic Oscillation (AO). The baroclinic response to AO, such as Ekman pumping in the Beaufort Gyre, and ice meldfreeze anomalies in response to AO are less significant considering the whole Arctic fresh <span class="hlt">water</span> balance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1916829D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1916829D"><span>Pacific <span class="hlt">Water</span> in the Arctic <span class="hlt">Ocean</span> and Fram Strait</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dodd, Paul; Blaesterdalen, Torgeir; Karcher, Michael; Stedmon, Colin</p> <p>2017-04-01</p> <p>The volume, characteristics and sources of freshwater circulating in the Arctic <span class="hlt">Ocean</span> vary in time and are expected to change under a declining sea ice cover, influencing the physical environment and Arctic ecosystem. Here we focus on relatively fresh (S = 32) Pacific <span class="hlt">Water</span>, which enters the Arctic <span class="hlt">Ocean</span> via the Bering Strait and makes up a significant part of the freshwater exiting the Arctic <span class="hlt">Ocean</span> through Fram Strait. More than 30 repeated sections of nutrient measurements were collected across Fram Strait between 1980 and 2015. The fraction of Pacific <span class="hlt">Water</span> along these repeated sections can be estimated from the ratio of nitrate to phosphate together with salinity. The time-series of repeated Fram Strait sections indicates that the fraction of Pacific <span class="hlt">Water</span> passing out of the Arctic <span class="hlt">Ocean</span> has changed significantly over the last 30 years. Pacific <span class="hlt">water</span> fractions remained high from 1980 to 1998, but in 1999 Pacific <span class="hlt">water</span> almost disappeared from Fram Strait, reappearing only briefly from 2011 to 2012. Several hypotheses suggest how variations in the large-scale atmospheric circulation over the Arctic <span class="hlt">Ocean</span> may influence the transport and pathways of Pacific <span class="hlt">Water</span>. Here we test those hypotheses by comparing established atmospheric indices with the long time series of repeated sections across Fram Strait. Repeated sections across Fram Strait are also compared with a simulated Pacific <span class="hlt">Water</span> tracer in the NAOSIM numerical model to further investigate the upstream drivers of changes observed in Fram Strait. The principle aim of this work is to identify the processes causing variability in freshwater fluxes out of the Arctic <span class="hlt">Ocean</span> so that we may better distinguish inter-annual variability from longer-term changes to the Arctic freshwater budget. However, the volume of fresh, silicate-rich Pacific <span class="hlt">water</span> exported from the Arctic <span class="hlt">Ocean</span> may also have implications for the ecosystem in the Nordic Seas.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_7");'>7</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li class="active"><span>9</span></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_9 --> <div id="page_10" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="181"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMNH23A1849W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMNH23A1849W"><span>The Long-term Performance of NOAA's Operational <span class="hlt">Open</span> <span class="hlt">Ocean</span> Tsunameter Array</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wasserman, J.; Bouchard, R. H.; Petraitis, D. C.; Rutledge, T. M.; Boudreaux, T. J.; Robbie, M. D.; Yarborough, S.; Fornea, G.</p> <p>2015-12-01</p> <p>The National <span class="hlt">Oceanic</span> and Atmospheric Administration's (NOAA) National Data Buoy Center (NDBC) has operated and maintained the full 39-station array of <span class="hlt">open</span> <span class="hlt">ocean</span> tsunameters since 2008 using the second generation Deep-<span class="hlt">ocean</span> Reporting and Assessment of Tsunamis technology. The array provides real-time, <span class="hlt">ocean</span> bottom measurements to Tsunami Warning Centers (TWC) located in Hawai'i and Alaska. These measurements aid them in detecting the presence or absence of tsunamis in the <span class="hlt">open</span> <span class="hlt">ocean</span> and in determining the essential characteristics of a tsunami to support the TWC. Thirty-two of the stations span the Pacific <span class="hlt">Ocean</span>, while seven are located in the Atlantic <span class="hlt">Ocean</span>, Gulf of Mexico, and the Caribbean Sea. The sensors are located on the <span class="hlt">ocean</span> floor to depths of 6000 m and the system must deliver measurements from that depth to the TWCs in 3 minutes or less. These vast horizontal and vertical distances and the often extreme conditions of the <span class="hlt">open</span> <span class="hlt">ocean</span> raise considerable challenges in maintaining necessary and sufficient measurements to support the TWCs. To support this effort, NDBC aims to maintain and generally achieves a goal of 80% real-time data availability. Data availability is the percentage of measurements received versus the number of expected measurements. Using seven years of data we examine operational performance parameters such as real-time and retrospective data availability and tsunami detection for trends, patterns, and the factors affecting performance and reliability of the array. We will also discuss the initial results of the Field Evaluation of the 4th Generation technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AIPC.1677f0021P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AIPC.1677f0021P"><span>Variation of <span class="hlt">ocean</span> pH in the Indonesia <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Putri, Mutiara Rachmat; Setiawan, Agus; Safitri, Mediana</p> <p>2015-09-01</p> <p>The variation of <span class="hlt">ocean</span> acidity (pH) in the Indonesia <span class="hlt">waters</span> is strongly influenced by monsoon. Since the climate change tends to potentially change monsoonal variation over the Indonesian region, it will give also implication to the <span class="hlt">ocean</span> pH variation. Moreover, changes of <span class="hlt">ocean</span> pH will give effects to the marine lifes and their environment. In order to investigate this issue, we tried to calculate monthly variation of sea surface pH in the Indonesia <span class="hlt">waters</span> based on monthly average temperature and salinity over past 18 years data. Temperature and salinity data used in this study were taken from the hydrodynamic model of Hamburg Shelf <span class="hlt">Ocean</span> Model (HAMSOM), while alkalinity and dissolved inorganic carbon (DIC) were from World <span class="hlt">Ocean</span> Atlas 2009 (WOA 2009). Algorithm from <span class="hlt">Ocean</span> Carbon Model Intercomparison Project-version.3 (OCMIP-3) was used to calculate the pH. The estimation results indicate that pH variation in the Indonesia <span class="hlt">waters</span> changes insignificantly over 18 years. El Nino Southern Oscillation (ENSO) and Indian <span class="hlt">Ocean</span> Dipole (IOD) contribute to physical changes of seawater, but did not affect the pH significantly. The average pH of seawater is higher during northwest monsoon than during southeast monsoon.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017DSRII.140..212D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017DSRII.140..212D"><span>Lagrangian analysis of multi-satellite data in support of <span class="hlt">open</span> <span class="hlt">ocean</span> Marine Protected Area design</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Della Penna, Alice; Koubbi, Philippe; Cotté, Cedric; Bon, Cécile; Bost, Charles-André; d'Ovidio, Francesco</p> <p>2017-06-01</p> <p>Compared to ecosystem conservation in territorial seas, protecting the <span class="hlt">open</span> <span class="hlt">ocean</span> has peculiar geopolitical, economic and scientific challenges. One of the major obstacle is defining the boundary of an <span class="hlt">open</span> <span class="hlt">ocean</span> Marine Protected Area (MPA). In contrast to coastal ecosystems, which are mostly constrained by topographic structures fixed in time, the life of marine organisms in the <span class="hlt">open</span> <span class="hlt">ocean</span> is entrained by fluid dynamical structures like eddies and fronts, whose lifetime occurs on ecologically-relevant timescales. The position of these highly dynamical structures can vary interannually by hundreds of km, and so too will regions identified as ecologically relevant such as the foraging areas of marine predators. Thus, the expected foraging locations suggested from tracking data cannot be directly extrapolated beyond the year in which the data were collected. Here we explore the potential of Lagrangian methods applied to multisatellite data as a support tool for a MPA proposal by focusing on the Crozet archipelago <span class="hlt">oceanic</span> area (Indian Sector of the Southern <span class="hlt">Ocean</span>). By combining remote sensing with biologging information from a key marine top predator (Eudyptes chrysolophus, or Macaroni penguin) of the Southern <span class="hlt">Ocean</span> foodweb, we identify a highly dynamic branch of the Subantarctic front as a foraging hotspot. By tracking this feature in historical satellite data (1993-2012) we are able to extrapolate the position of this foraging ground beyond the years in which tracking data are available and study its spatial variability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20020676','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20020676"><span>Photoreactions of mercury in surface <span class="hlt">ocean</span> <span class="hlt">water</span>: gross reaction kinetics and possible pathways.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Qureshi, Asif; O'Driscoll, Nelson J; MacLeod, Matthew; Neuhold, Yorck-Michael; Hungerbühler, Konrad</p> <p>2010-01-15</p> <p>We present pseudofirst order rate constants for gross photoreduction and gross photooxidation of mercury in surface <span class="hlt">water</span> from the <span class="hlt">open</span> Atlantic <span class="hlt">Ocean</span>, determined under controlled laboratory conditions. Experiments using both unfiltered and filtered <span class="hlt">ocean</span> <span class="hlt">water</span> were carried out to characterize the importance of microbes and colloids on reaction kinetics. Results indicate that reduction and oxidation of mercury in <span class="hlt">ocean</span> <span class="hlt">water</span> does not follow a simple two-species reversible reaction pathway. We suggest two possible redox pathways that reproduce the pattern of dissolved gaseous mercury (DGM) concentrations observed in our laboratory experiments, and evaluate them using a controlled outdoor experiment. In both proposed pathways Hg(0), the major constituent of DGM, is converted to an unidentified oxidized species that is different from the reducible form present initially. This reaction step plays a major role in the net formation of DGM in our experiments. Our results represent new quantitative information about the gross reaction kinetics for both reduction and oxidation of mercury in <span class="hlt">open</span> <span class="hlt">ocean</span> surface <span class="hlt">water</span>. Pseudofirst order rate constants for reduction reactions that form DGM were determined to be in the range of 0.15-0.93 h(-1) and pseudofirst order rate constants for oxidation of Hg(0) to be in the range of 0.4-1.9 h(-1). Microbes and colloids did not appreciably influence the reduction and oxidation kinetics.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1111548','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1111548"><span>DE-EE0000319 Final Technical Report [National <span class="hlt">Open-ocean</span> Energy Laboratory</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Skemp, Susan</p> <p>2013-12-29</p> <p>Under the authorization provided by Section 634 of the Energy Independence and Security Act of 2007 (P.L. 110-140), in 2009 FAU was awarded U.S. Congressionally Directed Program (CDP) funding through the U.S. Department of Energy (DOE) to investigate and develop technologies to harness the energy of the Florida Current as a source of clean, renewable, base-load power for Florida and the U.S. A second CDP award in 2010 provided additional funding in order to enhance and extend FAU’s activities. These two CDPs in 2009 and 2010 were combined into a single DOE grant, DE-EE0000319, and are the subject of this report. Subsequently, in July 2010 funding was made available under a separate contract, DE-EE0004200. Under that funding, DOE’s Wind and <span class="hlt">Water</span> Power Program designated FAU’s state of Florida marine renewable energy (MRE) center as the Southeast National Marine Renewable Energy Center (SNMREC). This report discusses SNMREC activities funded by the DE-EE0000319 grant, but will make reference, as appropriate, to activities that require further investigation under the follow-on grant. The concept of extracting energy from the motions of the <span class="hlt">oceans</span> has a long history. However, implementation on large scales of the technologies to effect renewable energy recovery from waves, tides, and <span class="hlt">open-ocean</span> currents is relatively recent. DOE’s establishment of SNMREC recognizes a significant potential for <span class="hlt">ocean</span> current energy recovery associated with the (relatively) high-speed Florida Current, the reach of the Gulf Stream System flowing through the Straits of Florida, between the Florida Peninsula and the Bahamas Archipelago. The proximity of the very large electrical load center of southeast Florida’s metropolitan area to the resource itself makes this potential all the more attractive. As attractive as this potential energy source is, it is not without its challenges. Although the technology is conceptually simple, its design and implementation in a commercially</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7026695','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7026695"><span>Seawater test results of <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) components</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zangrando, F.; Bharathan, D.; Link, H. ); Panchal, C.B. )</p> <p>1994-01-01</p> <p>Key components of <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion systems--the flash evaporator, mist eliminator, passive predeaerator, two surface condenser stages, and two direct-contact condenser stages--have been tested using seawater. These components operate at lower steam pressures and higher inlet noncondensable gas concentrations than do conventional power plant heat exchangers. The rate of heat exchanged between the evaporator and the condenser is on the order of 1.25MW-thermal, requiring a warm seawater flow of about 0.1 m[sup 3]/s; the cold seawater flow is on the order of half the warm <span class="hlt">water</span> flow. In addition to characterizing the performance of the various components, the system has produced potable <span class="hlt">water</span> from condensation of the steam produced in the evaporator. The information obtained in these tests is being used to design a larger scale experiment in which net power production is expected to be demonstrate for the first time using OC-OTEC technology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JPhA...46y4023D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JPhA...46y4023D"><span>Ecological implications of eddy retention in the <span class="hlt">open</span> <span class="hlt">ocean</span>: a Lagrangian approach</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>d'Ovidio, Francesco; De Monte, Silvia; Della Penna, Alice; Cotté, Cedric; Guinet, Christophe</p> <p>2013-06-01</p> <p>The repartition of tracers in the ocean’s upper layer on the scale of a few tens of kilometres is largely determined by the horizontal transport induced by surface currents. Here we consider surface currents detected from satellite altimetry (Jason and Envisat missions) and we study how surface <span class="hlt">waters</span> may be trapped by mesoscale eddies through a semi-Lagrangian diagnostic which combines the Lyapunov approach with Eulerian techniques. Such a diagnostic identifies the regions of the ocean’s upper layer with different retention times that appear to influence the behaviour of a tagged marine predator (an elephant seal) along a foraging trip. The comparison between predator trajectory and eddy retention time suggests that <span class="hlt">water</span> trapping by mesoscale eddies, derived from satellite altimetry, may be an important factor for monitoring hotspots of trophic interactions in the <span class="hlt">open</span> <span class="hlt">ocean</span>. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Lyapunov analysis: from dynamical systems theory to applications’.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150005639&hterms=submesoscale&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsubmesoscale','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150005639&hterms=submesoscale&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsubmesoscale"><span>The Proposed Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) Mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fu, Lee-Lueng; Alsdorf, Douglas; Rodriguez, Ernesto; Morrow, Rosemary; Mognard, Nelly; Vaze, Parag; Lafon, Thierry</p> <p>2012-01-01</p> <p>A new space mission concept called Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) is being developed jointly by a collaborative effort of the international oceanographic and hydrological communities for making high-resolution measurement of the <span class="hlt">water</span> elevation of both the <span class="hlt">ocean</span> and land surface <span class="hlt">water</span> to answer the questions about the <span class="hlt">oceanic</span> submesoscale processes and the storage and discharge of land surface <span class="hlt">water</span>. The key instrument payload would be a Ka-band radar interferometer capable of making high-resolution wide-swath altimetry measurement. This paper describes the proposed science objectives and requirements as well as the measurement approach of SWOT, which is baselined to be launched in 2019. SWOT would demonstrate this new approach to advancing both oceanography and land hydrology and set a standard for future altimetry missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20150005639&hterms=Topography&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DTopography','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20150005639&hterms=Topography&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3DTopography"><span>The Proposed Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) Mission</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fu, Lee-Lueng; Alsdorf, Douglas; Rodriguez, Ernesto; Morrow, Rosemary; Mognard, Nelly; Vaze, Parag; Lafon, Thierry</p> <p>2012-01-01</p> <p>A new space mission concept called Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) is being developed jointly by a collaborative effort of the international oceanographic and hydrological communities for making high-resolution measurement of the <span class="hlt">water</span> elevation of both the <span class="hlt">ocean</span> and land surface <span class="hlt">water</span> to answer the questions about the <span class="hlt">oceanic</span> submesoscale processes and the storage and discharge of land surface <span class="hlt">water</span>. The key instrument payload would be a Ka-band radar interferometer capable of making high-resolution wide-swath altimetry measurement. This paper describes the proposed science objectives and requirements as well as the measurement approach of SWOT, which is baselined to be launched in 2019. SWOT would demonstrate this new approach to advancing both oceanography and land hydrology and set a standard for future altimetry missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/20448197','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/20448197"><span>Seamounts are hotspots of pelagic biodiversity in the <span class="hlt">open</span> <span class="hlt">ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Morato, Telmo; Hoyle, Simon D; Allain, Valerie; Nicol, Simon J</p> <p>2010-05-25</p> <p>The identification of biodiversity hotspots and their management for conservation have been hypothesized as effective ways to protect many species. There has been a significant effort to identify and map these areas at a global scale, but the coarse resolution of most datasets masks the small-scale patterns associated with coastal habitats or seamounts. Here we used tuna longline observer data to investigate the role of seamounts in aggregating large pelagic biodiversity and to identify which pelagic species are associated with seamounts. Our analysis indicates that seamounts are hotspots of pelagic biodiversity. Higher species richness was detected in association with seamounts than with coastal or <span class="hlt">oceanic</span> areas. Seamounts were found to have higher species diversity within 30-40 km of the summit, whereas for sets close to coastal habitat the diversity was lower and fairly constant with distance. Higher probability of capture and higher number of fish caught were detected for some shark, billfish, tuna, and other by-catch species. The study supports hypotheses that seamounts may be areas of special interest for management for marine pelagic predators.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2906904','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2906904"><span>Seamounts are hotspots of pelagic biodiversity in the <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Morato, Telmo; Hoyle, Simon D.; Allain, Valerie; Nicol, Simon J.</p> <p>2010-01-01</p> <p>The identification of biodiversity hotspots and their management for conservation have been hypothesized as effective ways to protect many species. There has been a significant effort to identify and map these areas at a global scale, but the coarse resolution of most datasets masks the small-scale patterns associated with coastal habitats or seamounts. Here we used tuna longline observer data to investigate the role of seamounts in aggregating large pelagic biodiversity and to identify which pelagic species are associated with seamounts. Our analysis indicates that seamounts are hotspots of pelagic biodiversity. Higher species richness was detected in association with seamounts than with coastal or <span class="hlt">oceanic</span> areas. Seamounts were found to have higher species diversity within 30–40 km of the summit, whereas for sets close to coastal habitat the diversity was lower and fairly constant with distance. Higher probability of capture and higher number of fish caught were detected for some shark, billfish, tuna, and other by-catch species. The study supports hypotheses that seamounts may be areas of special interest for management for marine pelagic predators. PMID:20448197</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017CG....107...28B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017CG....107...28B"><span>WASS: An <span class="hlt">open</span>-source pipeline for 3D stereo reconstruction of <span class="hlt">ocean</span> waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bergamasco, Filippo; Torsello, Andrea; Sclavo, Mauro; Barbariol, Francesco; Benetazzo, Alvise</p> <p>2017-10-01</p> <p>Stereo 3D reconstruction of <span class="hlt">ocean</span> waves is gaining more and more popularity in the oceanographic community and industry. Indeed, recent advances of both computer vision algorithms and computer processing power now allow the study of the spatio-temporal wave field with unprecedented accuracy, especially at small scales. Even if simple in theory, multiple details are difficult to be mastered for a practitioner, so that the implementation of a sea-waves 3D reconstruction pipeline is in general considered a complex task. For instance, camera calibration, reliable stereo feature matching and mean sea-plane estimation are all factors for which a well designed implementation can make the difference to obtain valuable results. For this reason, we believe that the <span class="hlt">open</span> availability of a well tested software package that automates the reconstruction process from stereo images to a 3D point cloud would be a valuable addition for future researches in this area. We present WASS (http://www.dais.unive.it/wass), an <span class="hlt">Open</span>-Source stereo processing pipeline for sea waves 3D reconstruction. Our tool completely automates all the steps required to estimate dense point clouds from stereo images. Namely, it computes the extrinsic parameters of the stereo rig so that no delicate calibration has to be performed on the field. It implements a fast 3D dense stereo reconstruction procedure based on the consolidated <span class="hlt">Open</span>CV library and, lastly, it includes set of filtering techniques both on the disparity map and the produced point cloud to remove the vast majority of erroneous points that can naturally arise while analyzing the optically complex nature of the <span class="hlt">water</span> surface. In this paper, we describe the architecture of WASS and the internal algorithms involved. The pipeline workflow is shown step-by-step and demonstrated on real datasets acquired at sea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121.3866C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121.3866C"><span>Improving satellite data products for <span class="hlt">open</span> <span class="hlt">oceans</span> with a scheme to correct the residual errors in remote sensing reflectance</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Chen, Jun; Lee, Zhongping; Hu, Chuanmin; Wei, Jianwei</p> <p>2016-06-01</p> <p>An approach to semianalytically derive <span class="hlt">waters</span>' inherent optical properties (IOPs) from remote sensing reflectance (Rrs) and at the same time to take into account the residual errors in satellite Rrs is developed for <span class="hlt">open-ocean</span> clear <span class="hlt">waters</span> where aerosols are likely of marine origin. This approach has two components: (1) a scheme of combining a neural network and an algebraic solution for the derivation of IOPs, and (2) relationships between Rrs residual errors at 670 nm and other spectral bands. This approach is evaluated with both synthetic and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) data, and the results show that it can significantly reduce the effects of residual errors in Rrs on the retrieval of IOPs, and at the same time remove partially the Rrs residual errors for "low-quality" and "high-quality" data defined in this study. Furthermore, more consistent estimation of chlorophyll concentrations between the empirical blue-green ratio and band-difference algorithms can be derived from the corrected "low-quality" and "high-quality" Rrs. These results suggest that it is possible to improve both data quality and quantity of satellite-retrieved Rrs over clear <span class="hlt">open-ocean</span> <span class="hlt">waters</span> with a step considering the spectral relationships of the residual errors in Rrs after the default atmospheric correction procedure and without fixing Rrs at 670 nm to one value for clear <span class="hlt">waters</span> in a small region such as 3 × 3 box.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9827E..11A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9827E..11A"><span>Diurnal changes in <span class="hlt">ocean</span> color in coastal <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arnone, Robert; Vandermeulen, Ryan; Ladner, Sherwin; Ondrusek, Michael; Kovach, Charles; Yang, Haoping; Salisbury, Joseph</p> <p>2016-05-01</p> <p>Coastal processes can change on hourly time scales in response to tides, winds and biological activity, which can influence the color of surface <span class="hlt">waters</span>. These temporal and spatial <span class="hlt">ocean</span> color changes require satellite validation for applications using bio-optical products to delineate diurnal processes. The diurnal color change and capability for satellite <span class="hlt">ocean</span> color response were determined with in situ and satellite observations. Hourly variations in satellite <span class="hlt">ocean</span> color are dependent on several properties which include: a) sensor characterization b) advection of <span class="hlt">water</span> masses and c) diurnal response of biological and optical <span class="hlt">water</span> properties. The in situ diurnal changes in <span class="hlt">ocean</span> color in a dynamic turbid coastal region in the northern Gulf of Mexico were characterized using above <span class="hlt">water</span> spectral radiometry from an AErosol RObotic NETwork (AERONET -WavCIS CSI-06) site that provides up to 8-10 observations per day (in 15-30 minute increments). These in situ diurnal changes were used to validate and quantify natural bio-optical fluctuations in satellite <span class="hlt">ocean</span> color measurements. Satellite capability to detect changes in <span class="hlt">ocean</span> color was characterized by using overlapping afternoon orbits of the VIIRS-NPP <span class="hlt">ocean</span> color sensor within 100 minutes. Results show the capability of multiple satellite observations to monitor hourly color changes in dynamic coastal regions that are impacted by tides, re-suspension, and river plume dispersion. Hourly changes in satellite <span class="hlt">ocean</span> color were validated with in situ observation on multiple occurrences during different times of the afternoon. Also, the spatial variability of VIIRS diurnal changes shows the occurrence and displacement of phytoplankton blooms and decay during the afternoon period. Results suggest that determining the temporal and spatial changes in a color / phytoplankton bloom from the morning to afternoon time period will require additional satellite coverage periods in the coastal zone.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA617682','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA617682"><span><span class="hlt">Ocean</span> Ambient Noise Studies for Shallow and Deep <span class="hlt">Water</span> Environments</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2014-09-30</p> <p>1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. <span class="hlt">Ocean</span> Ambient Noise Studies for Shallow and Deep <span class="hlt">Water</span>...Siderius.php LONG-TERM GOALS The objective of this research is to study the <span class="hlt">ocean</span> ambient noise field by means of new physics-based processing... ambient -noise field using a vertical line array has been developed by Harrison and Simons [Harrison, 2002]. The advantages of passive bottom-survey</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000110129&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000110129&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span> and at Landfall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walsh, E. J.; Wright, C. W.; Vandemark, D.; Krabill, W. B.; Garcia, A. W.; Houston, S. H.; Powell, M. D.; Black, P. G.; Marks, F. D.; Busalacchi, Antonio J. (Technical Monitor)</p> <p>2000-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane hunter aircraft at 1.5 km height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. At 8 Hz, the SRA sweeps a radar beam of 1 E half-power width (two-way) across the aircraft ground track over a swath equal to 0.8 of the aircraft height, simultaneously measuring the backscattered power at its 36 GHz (8.3 mm) operating frequency and the range to the sea surface at 64 positions. These slant ranges are multiplied by the cosine of the incidence angles to determine the vertical distances from the aircraft to the sea surface. Subtracting these distances from the aircraft height produces the sea surface elevation map. The sea surface topography is interpolated to a uniform grid, transformed by a two-dimensional FFT, and Doppler corrected. The <span class="hlt">open-ocean</span> data were acquired on 24 August 1998 when hurricane Bonnie was east of the Bahamas and moving slowly to the north. Individual waves with heights up to 18 m were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At some positions there were three different wave fields of comparable energy crossing each other. The NOAA aircraft spent over five hours within 180 km of the hurricane Bonnie eye, and made five eye penetrations. A 3-minute animation of the directional wave spectrum spatial variation over this period will be shown as well as summary plots of the wave field spatial variation. On 26 August 1998, the NOAA aircraft flew at 2.2 km height when hurricane Bonnie was making landfall near Wilmington, NC, documenting the directional wave spectrum in the region between Charleston, SC and Cape Hatteras, NC. The aircraft ground track</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000110129&hterms=ocean+power&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Docean%2Bpower','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000110129&hterms=ocean+power&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Docean%2Bpower"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span> and at Landfall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walsh, E. J.; Wright, C. W.; Vandemark, D.; Krabill, W. B.; Garcia, A. W.; Houston, S. H.; Powell, M. D.; Black, P. G.; Marks, F. D.; Busalacchi, Antonio J. (Technical Monitor)</p> <p>2000-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane hunter aircraft at 1.5 km height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. At 8 Hz, the SRA sweeps a radar beam of 1 E half-power width (two-way) across the aircraft ground track over a swath equal to 0.8 of the aircraft height, simultaneously measuring the backscattered power at its 36 GHz (8.3 mm) operating frequency and the range to the sea surface at 64 positions. These slant ranges are multiplied by the cosine of the incidence angles to determine the vertical distances from the aircraft to the sea surface. Subtracting these distances from the aircraft height produces the sea surface elevation map. The sea surface topography is interpolated to a uniform grid, transformed by a two-dimensional FFT, and Doppler corrected. The <span class="hlt">open-ocean</span> data were acquired on 24 August 1998 when hurricane Bonnie was east of the Bahamas and moving slowly to the north. Individual waves with heights up to 18 m were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At some positions there were three different wave fields of comparable energy crossing each other. The NOAA aircraft spent over five hours within 180 km of the hurricane Bonnie eye, and made five eye penetrations. A 3-minute animation of the directional wave spectrum spatial variation over this period will be shown as well as summary plots of the wave field spatial variation. On 26 August 1998, the NOAA aircraft flew at 2.2 km height when hurricane Bonnie was making landfall near Wilmington, NC, documenting the directional wave spectrum in the region between Charleston, SC and Cape Hatteras, NC. The aircraft ground track</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25112842','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25112842"><span>Biological response to physical processes in the Indian <span class="hlt">Ocean</span> sector of the Southern <span class="hlt">Ocean</span>: a case study in the coastal and <span class="hlt">oceanic</span> <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Anilkumar, N; Chacko, Racheal; Sabu, P; Pillai, Honey U K; George, Jenson V; Achuthankutty, C T</p> <p>2014-12-01</p> <p>The spatial variation of chlorophyll a (Chl a) and factors influencing the high Chl a were studied during austral summer based on the physical and biogeochemical parameters collected near the coastal <span class="hlt">waters</span> of Antarctica in 2010 and a zonal section along 60°S in 2011. In the coastal <span class="hlt">waters</span>, high Chl a (>3 mg m(-3)) was observed near the upper layers (∼15 m) between 53°30'E and 54°30'E. A comparatively higher mesozooplankton biomass (53.33 ml 100 m(-3)) was also observed concordant with the elevated Chl a. Low saline <span class="hlt">water</span> formed by melting of glacial ice and snow, as well as deep mixed-layer depth (60 m) due to strong wind (>11 ms(-1)) could be the dominant factors for this biological response. In the <span class="hlt">open</span> <span class="hlt">ocean</span>, moderately high surface Chl a was observed (>0.6 mg m(-3)) between 47°E and 50°E along with a Deep Chlorophyll Maximum of ∼1 mg m(-3) present at 30-40 m depth. Melt <span class="hlt">water</span> advected from the Antarctic continent could be the prime reason for this high Chl a. The mesozooplankton biomass (22.76 ml 100 m(-3)) observed in the <span class="hlt">open</span> <span class="hlt">ocean</span> was comparatively lower than that in the coastal <span class="hlt">waters</span>. Physical factors such as melting, advection of melt <span class="hlt">water</span> from Antarctic continent, <span class="hlt">water</span> masses and wind-induced vertical mixing may be the possible reasons that led to the increase in phytoplankton biomass (Chl a).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3578572','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3578572"><span>Gradients in microbial methanol uptake: productive coastal upwelling <span class="hlt">waters</span> to oligotrophic gyres in the Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dixon, Joanna L; Sargeant, Stephanie; Nightingale, Philip D; Colin Murrell, J</p> <p>2013-01-01</p> <p>Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling <span class="hlt">waters</span> of up to 0.117±0.002 d−1 (∼10 nmol l−1 d−1). On average, coastal upwelling <span class="hlt">waters</span> were 11 times greater than <span class="hlt">open</span> <span class="hlt">ocean</span> northern temperate (NT) <span class="hlt">waters</span>, eight times greater than gyre <span class="hlt">waters</span> and four times greater than equatorial upwelling (EU) <span class="hlt">waters</span>; suggesting that all upwelling <span class="hlt">waters</span> upon reaching the surface (⩽20 m), contain a microbial population that uses a relatively high amount of carbon (0.3–10 nmol l−1 d−1), derived from methanol, to support their growth. In <span class="hlt">open</span> <span class="hlt">ocean</span> Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04–0.68 nmol l−1 d−1. Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre <span class="hlt">waters</span>. Several methylotrophic bacterial species were identified from <span class="hlt">open</span> <span class="hlt">ocean</span> Atlantic <span class="hlt">waters</span> using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling <span class="hlt">waters</span> between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air–sea exchange scientists. PMID:23178665</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23178665','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23178665"><span>Gradients in microbial methanol uptake: productive coastal upwelling <span class="hlt">waters</span> to oligotrophic gyres in the Atlantic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dixon, Joanna L; Sargeant, Stephanie; Nightingale, Philip D; Colin Murrell, J</p> <p>2013-03-01</p> <p>Methanol biogeochemistry and its importance as a carbon source in seawater is relatively unexplored. We report the first microbial methanol carbon assimilation rates (k) in productive coastal upwelling <span class="hlt">waters</span> of up to 0.117±0.002 d(-1) (~10 nmol l(-1 )d(-1)). On average, coastal upwelling <span class="hlt">waters</span> were 11 times greater than <span class="hlt">open</span> <span class="hlt">ocean</span> northern temperate (NT) <span class="hlt">waters</span>, eight times greater than gyre <span class="hlt">waters</span> and four times greater than equatorial upwelling (EU) <span class="hlt">waters</span>; suggesting that all upwelling <span class="hlt">waters</span> upon reaching the surface (≤20 m), contain a microbial population that uses a relatively high amount of carbon (0.3-10 nmol l(-1 )d(-1)), derived from methanol, to support their growth. In <span class="hlt">open</span> <span class="hlt">ocean</span> Atlantic regions, microbial uptake of methanol into biomass was significantly lower, ranging between 0.04-0.68 nmol l(-1 )d(-1). Microbes in the Mauritanian coastal upwelling used up to 57% of the total methanol for assimilation of the carbon into cells, compared with an average of 12% in the EU, and 1% in NT and gyre <span class="hlt">waters</span>. Several methylotrophic bacterial species were identified from <span class="hlt">open</span> <span class="hlt">ocean</span> Atlantic <span class="hlt">waters</span> using PCR amplification of mxaF encoding methanol dehydrogenase, the key enzyme in bacterial methanol oxidation. These included Methylophaga sp., Burkholderiales sp., Methylococcaceae sp., Ancylobacter aquaticus, Paracoccus denitrificans, Methylophilus methylotrophus, Methylobacterium oryzae, Hyphomicrobium sp. and Methylosulfonomonas methylovora. Statistically significant correlations for upwelling <span class="hlt">waters</span> between methanol uptake into cells and both chlorophyll a concentrations and methanol oxidation rates suggest that remotely sensed chlorophyll a images, in these productive areas, could be used to derive total methanol biological loss rates, a useful tool for atmospheric and marine climatically active gas modellers, and air-sea exchange scientists.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.H33M..01T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.H33M..01T"><span><span class="hlt">Water</span> security and services in the <span class="hlt">ocean</span>-aquifer system</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Taniguchi, M.</p> <p>2011-12-01</p> <p>Coastal vulnerability and <span class="hlt">water</span> security are both important research subjects on global environmental problems under the pressures of changing climate and societies. A six years research project by RIHN on the coastal subsurface environments in seven Asia cities revealed that subsurface environmental problems including saltwater intrusion, groundwater contamination and subsurface thermal anomalies occurred one after another depending on the development stage of the cities during the last 100 years. Exchanges of <span class="hlt">water</span> between <span class="hlt">ocean</span> and aquifer in the coastal cities depend on driving force from land of natural resources capacities such as groundwater recharge rate, and social changes such as excessive groundwater pumping due to industrialization. Risk assessments and managements for aquifers which are parts of <span class="hlt">water</span> security have been made for seven Asian coastal cities. On the other hand, submarine groundwater discharge (SGD) into the <span class="hlt">ocean</span> provides <span class="hlt">water</span> services directly to the coastal ecosystem through nutrient transports from land to the <span class="hlt">ocean</span>. Constant geophysical and geochemical conditions served by SGD provide sustainable services to the coastal environment. Flora and fauna which prefer brackish <span class="hlt">water</span> in the coastal zone depend on not only river <span class="hlt">water</span> discharge but also SGD. <span class="hlt">Ocean</span> -aquifer interaction can be found in the coastal ecosystem including sea shell, sea grass and fishes in the coastal zone though SGD. In order to evaluate a coastal security and sustainable environment, not only risk assessments due to disasters but also <span class="hlt">water</span> services are important, and the both are evaluated in Asian coastal zones.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19800004466','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19800004466"><span>Data Requirements for <span class="hlt">Oceanic</span> Processes in the <span class="hlt">Open</span> <span class="hlt">Ocean</span>, Coastal Zone, and Cryosphere</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Nagler, R. G.; Mccandless, S. W., Jr.</p> <p>1978-01-01</p> <p>The type of information system that is needed to meet the requirements of <span class="hlt">ocean</span>, coastal, and polar region users was examined. The requisite qualities of the system are: (1) availability, (2) accessibility, (3) responsiveness, (4) utility, (5) continuity, and (6) NASA participation. The system would not displace existing capabilities, but would have to integrate and expand the capabilities of existing systems and resolve the deficiencies that currently exist in producer-to-user information delivery options.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27656005','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27656005"><span>Mercury in Marine and <span class="hlt">Oceanic</span> <span class="hlt">Waters</span>-a Review.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gworek, Barbara; Bemowska-Kałabun, Olga; Kijeńska, Marta; Wrzosek-Jakubowska, Justyna</p> <p></p> <p>Mercury contamination in <span class="hlt">water</span> has been an issue to the environment and human health. In this article, mercury in marine and <span class="hlt">oceanic</span> <span class="hlt">waters</span> has been reviewed. In the aquatic environment, mercury occurs in many forms, which depend on the oxidation-reduction conditions. These forms have been briefly described in this article. Mercury concentrations in marine <span class="hlt">waters</span> in the different parts of the world have been presented. In the relevant literature, two models describing the fate and behavior of mercury in saltwater reservoirs have been presented, a conceptual model which treats all the <span class="hlt">oceans</span> as one <span class="hlt">ocean</span> and the "<span class="hlt">ocean</span> margin" model, providing that the <span class="hlt">ocean</span> margins manifested themselves as the convergence of continents and <span class="hlt">oceans</span>, covering such geological features, such as estuaries, inland seas, and the continental shelf. These two conceptual models have been summarized in the text. The mercury content in benthic sediments usually reflects is level in the <span class="hlt">water</span> reservoir, particularly in reservoirs situated in contaminated areas (mines, metallurgical plants, chemically protected crops). The concentrations of mercury and its compounds determined in the sediments in surface <span class="hlt">waters</span> in the different parts of the world have been presented. Due to the fact that the pollution caused by mercury is a serious threat for the marine environment, the short paragraph about mercury bioaccumulation in aquatic organisms has been included. The cited data demonstrated a large scatter of mercury contents both between the fish species and the <span class="hlt">water</span> areas. Mathematical models, valuable tools which provide information about the possible responses of ecosystems, developed to simulate mercury emissions, both at a small scale, for local <span class="hlt">water</span> reservoirs, and at a global scale, as well as to model mercury bioaccumulation in the chain web of aquatic systems have been described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900034376&hterms=properties+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dproperties%2Bwater','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900034376&hterms=properties+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3Dproperties%2Bwater"><span>Raman scattering and in-<span class="hlt">water</span> <span class="hlt">ocean</span> optical properties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Marshall, Bruce R.; Smith, Raymond C.</p> <p>1990-01-01</p> <p>Inelastic (transpectral) scattering may contribute significantly to the in-<span class="hlt">water</span> light field. Major mechanisms for inelastic scattering include Raman scattering, which is important in clear <span class="hlt">ocean</span> <span class="hlt">waters</span>, and fluorescence from a variety of sources, which may be important in more turbid <span class="hlt">waters</span>. The Raman cross section for liquid <span class="hlt">water</span> is found to be 8.2 x 10 to the -30th sq cm/sr molecule, which is in agreement with the lower range of published values. Inelastic scattering has important ramifications for several aspects of marine biooptics, including the determination of in-<span class="hlt">water</span> spectral absorption, the estimation of clear-<span class="hlt">water</span> <span class="hlt">ocean</span> optical properties, and possibly various aspects of algal photobiology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19900034376&hterms=monte+carlo+turbid+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmonte%2Bcarlo%2Bturbid%2Bwater','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19900034376&hterms=monte+carlo+turbid+water&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dmonte%2Bcarlo%2Bturbid%2Bwater"><span>Raman scattering and in-<span class="hlt">water</span> <span class="hlt">ocean</span> optical properties</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Marshall, Bruce R.; Smith, Raymond C.</p> <p>1990-01-01</p> <p>Inelastic (transpectral) scattering may contribute significantly to the in-<span class="hlt">water</span> light field. Major mechanisms for inelastic scattering include Raman scattering, which is important in clear <span class="hlt">ocean</span> <span class="hlt">waters</span>, and fluorescence from a variety of sources, which may be important in more turbid <span class="hlt">waters</span>. The Raman cross section for liquid <span class="hlt">water</span> is found to be 8.2 x 10 to the -30th sq cm/sr molecule, which is in agreement with the lower range of published values. Inelastic scattering has important ramifications for several aspects of marine biooptics, including the determination of in-<span class="hlt">water</span> spectral absorption, the estimation of clear-<span class="hlt">water</span> <span class="hlt">ocean</span> optical properties, and possibly various aspects of algal photobiology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25461969','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25461969"><span>Life-cycle modification in <span class="hlt">open</span> <span class="hlt">oceans</span> accounts for genome variability in a cosmopolitan phytoplankton.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>von Dassow, Peter; John, Uwe; Ogata, Hiroyuki; Probert, Ian; Bendif, El Mahdi; Kegel, Jessica U; Audic, Stéphane; Wincker, Patrick; Da Silva, Corinne; Claverie, Jean-Michel; Doney, Scott; Glover, David M; Flores, Daniella Mella; Herrera, Yeritza; Lescot, Magali; Garet-Delmas, Marie-José; de Vargas, Colomban</p> <p>2015-06-01</p> <p>Emiliania huxleyi is the most abundant calcifying plankton in modern <span class="hlt">oceans</span> with substantial intraspecific genome variability and a biphasic life cycle involving sexual alternation between calcified 2N and flagellated 1N cells. We show that high genome content variability in Emiliania relates to erosion of 1N-specific genes and loss of the ability to form flagellated cells. Analysis of 185 E. huxleyi strains isolated from world <span class="hlt">oceans</span> suggests that loss of flagella occurred independently in lineages inhabiting oligotrophic <span class="hlt">open</span> <span class="hlt">oceans</span> over short evolutionary timescales. This environmentally linked physiogenomic change suggests life cycling is not advantageous in very large/diluted populations experiencing low biotic pressure and low ecological variability. Gene loss did not appear to reflect pressure for genome streamlining in oligotrophic <span class="hlt">oceans</span> as previously observed in picoplankton. Life-cycle modifications might be common in plankton and cause major functional variability to be hidden from traditional taxonomic or molecular markers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26216947','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26216947"><span>Decadal acidification in the <span class="hlt">water</span> masses of the Atlantic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ríos, Aida F; Resplandy, Laure; García-Ibáñez, Maribel I; Fajar, Noelia M; Velo, Anton; Padin, Xose A; Wanninkhof, Rik; Steinfeldt, Reiner; Rosón, Gabriel; Pérez, Fiz F</p> <p>2015-08-11</p> <p>Global <span class="hlt">ocean</span> acidification is caused primarily by the <span class="hlt">ocean</span>'s uptake of CO2 as a consequence of increasing atmospheric CO2 levels. We present observations of the <span class="hlt">oceanic</span> decrease in pH at the basin scale (50 °S-36 °N) for the Atlantic <span class="hlt">Ocean</span> over two decades (1993-2013). Changes in pH associated with the uptake of anthropogenic CO2 (ΔpHCant) and with variations caused by biological activity and <span class="hlt">ocean</span> circulation (ΔpHNat) are evaluated for different <span class="hlt">water</span> masses. Output from an Institut Pierre Simon Laplace climate model is used to place the results into a longer-term perspective and to elucidate the mechanisms responsible for pH change. The largest decreases in pH (∆pH) were observed in central, mode, and intermediate <span class="hlt">waters</span>, with a maximum ΔpH value in South Atlantic Central <span class="hlt">Waters</span> of -0.042 ± 0.003. The ΔpH trended toward zero in deep and bottom <span class="hlt">waters</span>. Observations and model results show that pH changes generally are dominated by the anthropogenic component, which accounts for rates between -0.0015 and -0.0020/y in the central <span class="hlt">waters</span>. The anthropogenic and natural components are of the same order of magnitude and reinforce one another in mode and intermediate <span class="hlt">waters</span> over the time period. Large negative ΔpHNat values observed in mode and intermediate <span class="hlt">waters</span> are driven primarily by changes in CO2 content and are consistent with (i) a poleward shift of the formation region during the positive phase of the Southern Annular Mode in the South Atlantic and (ii) an increase in the rate of the <span class="hlt">water</span> mass formation in the North Atlantic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.A44D..02B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.A44D..02B"><span>Mercury Isotopic Evidence for Contrasting Mercury Transport Pathways to Coastal versus <span class="hlt">Open</span> <span class="hlt">Ocean</span> Fisheries (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Blum, J. D.; Senn, D. B.; Chesney, E. J.; Bank, M. S.; Maage, A.; Shine, J. P.</p> <p>2009-12-01</p> <p>Mercury stable isotopes provide a new method for tracing the sources and chemical transformations of Hg in the environment. In this study we used Hg isotopes to investigate Hg sources to coastal versus migratory <span class="hlt">open-ocean</span> species of fish residing in the northern Gulf of Mexico (nGOM). We report Hg isotope ratios as δ202Hg (mass dependent fractionation relative to NIST 3133) and Δ201Hg (mass independent fractionation of odd isotopes). In six coastal and two <span class="hlt">open</span> <span class="hlt">ocean</span> species (blackfin and yellowfin tuna), Hg isotopic compositions fell into two non-overlapping ranges. The tuna had significantly higher δ202Hg (0.1 to 0.7‰) and Δ201Hg (1.0 to 2.2‰) than the coastal fish (δ202Hg = 0 to -1.0‰; Δ201Hg = 0.4 to 0.5‰). The observations can be best explained by largely disconnected food webs with isotopically distinct MeHg sources. The ratio Δ199Hg/Δ201Hg in nGOM fish is 1.30±0.10 which is consistent with laboratory studies of photochemical MeHg degradation and with ratios measured in freshwater fish (Bergquist and Blum, 2007). The magnitude of mass independent fractionation of Hg in the <span class="hlt">open-ocean</span> fish suggests that this source of MeHg was subjected to extensive photodegradation (~50%) before entering the base of the <span class="hlt">open-ocean</span> food web. Given the Mississippi River’s large, productive footprint in the nGOM and the potential for exporting prey and MeHg to the adjacent oligotrophic GOM, the different MeHg sources are noteworthy and consistent with recent evidence in other systems of important <span class="hlt">open-ocean</span> MeHg sources. Bergquist, B. A. and Blum, J. D., 2007. Mass-dependent and -independent fractionation of Hg isotopes by photoreduction in aquatic systems. Science 318, 417-420.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16752440','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16752440"><span>Episodic fresh surface <span class="hlt">waters</span> in the Eocene Arctic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Brinkhuis, Henk; Schouten, Stefan; Collinson, Margaret E; Sluijs, Appy; Sinninghe Damsté, Jaap S; Dickens, Gerald R; Huber, Matthew; Cronin, Thomas M; Onodera, Jonaotaro; Takahashi, Kozo; Bujak, Jonathan P; Stein, Ruediger; van der Burgh, Johan; Eldrett, James S; Harding, Ian C; Lotter, André F; Sangiorgi, Francesca; van Konijnenburg-van Cittert, Han; de Leeuw, Jan W; Matthiessen, Jens; Backman, Jan; Moran, Kathryn</p> <p>2006-06-01</p> <p>It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain <span class="hlt">oceanic</span> conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic <span class="hlt">Ocean</span> by the onset of the middle Eocene epoch (approximately 50 Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface <span class="hlt">waters</span> during an approximately 800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic <span class="hlt">Ocean</span> that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from approximately 10 degrees C to 13 degrees C, pointing to simultaneous increases in salt and heat supply owing to the influx of <span class="hlt">waters</span> from adjacent <span class="hlt">oceans</span>. We suggest that onset and termination of the Azolla phase depended on the degree of <span class="hlt">oceanic</span> exchange between Arctic <span class="hlt">Ocean</span> and adjacent seas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70030357','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70030357"><span>Episodic fresh surface <span class="hlt">waters</span> in the Eocene Arctic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Brinkhuis, H.; Schouten, S.; Collinson, M.E.; Sluijs, A.; Damste, J.S.S.; Dickens, G.R.; Huber, M.; Cronin, T. M.; Onodera, J.; Takahashi, K.; Bujak, J.P.; Stein, R.; Van Der Burgh, J.; Eldrett, J.S.; Harding, I.C.; Lotter, A.F.; Sangiorgi, F.; Cittert, H.V.K.V.; De Leeuw, J. W.; Matthiessen, J.; Backman, J.; Moran, K.</p> <p>2006-01-01</p> <p>It has been suggested, on the basis of modern hydrology and fully coupled palaeoclimate simulations, that the warm greenhouse conditions that characterized the early Palaeogene period (55-45 Myr ago) probably induced an intensified hydrological cycle with precipitation exceeding evaporation at high latitudes. Little field evidence, however, has been available to constrain <span class="hlt">oceanic</span> conditions in the Arctic during this period. Here we analyse Palaeogene sediments obtained during the Arctic Coring Expedition, showing that large quantities of the free-floating fern Azolla grew and reproduced in the Arctic <span class="hlt">Ocean</span> by the onset of the middle Eocene epoch (???50 Myr ago). The Azolla and accompanying abundant freshwater organic and siliceous microfossils indicate an episodic freshening of Arctic surface <span class="hlt">waters</span> during an ???800,000-year interval. The abundant remains of Azolla that characterize basal middle Eocene marine deposits of all Nordic seas probably represent transported assemblages resulting from freshwater spills from the Arctic <span class="hlt">Ocean</span> that reached as far south as the North Sea. The termination of the Azolla phase in the Arctic coincides with a local sea surface temperature rise from ???10??C to 13??C, pointing to simultaneous increases in salt and heat supply owing to the influx of <span class="hlt">waters</span> from adjacent <span class="hlt">oceans</span>. We suggest that onset and termination of the Azolla phase depended on the degree of <span class="hlt">oceanic</span> exchange between Arctic <span class="hlt">Ocean</span> and adjacent seas. ?? 2006 Nature Publishing Group.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS43E1874L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS43E1874L"><span>Separating Internal Waves and Vortical Structure in the <span class="hlt">Open</span> <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lauffenburger, N. E.; Sanford, T. B.; Lien, R.</p> <p>2012-12-01</p> <p>Deviating from past oceanographic surveys, a new, powerful array of profiling floats has been deployed for three weeks in the Sargasso Sea to monitor the evolving sub-mesoscale field. Using 18-20 EM-APEX floats, profiling to 100 m depth simultaneously, velocity (U and V), temperature, salinity and microstructure measurements (χ) were made on horizontal scales between 100 m and 10 km. This strategy provided a 3-D snapshot of the physical properties every half hour, which significantly reduces temporal aliasing. Area-averaged relative vorticity, vortex stretching, non-linear twisting, horizontal divergence and Ertel's potential vorticity have been computed and projected onto isopycnal surfaces. Since vortical modes carry Ertel's potential vorticity (and internal waves do not), this is a useful step in understanding the energetic contribution of vortical motions to the background internal wave field on small scales. In addition, the temporal material conservation law of Ertel's potential vorticity will be tested for the first time by determining the advection of the floats' measurements relative to the motion of the <span class="hlt">water</span> parcels and by computing the horizontal gradients of the potential vorticity signal. The three deployments provide data to analyze the interaction of inertial waves, vortical processes and barotropic tides in and out of active frontogenesis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..18.8998K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..18.8998K"><span>A multidisciplinary glider survey of an <span class="hlt">open</span> <span class="hlt">ocean</span> dead-zone eddy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Karstensen, Johannes; Schütte, Florian; Pietri, Alice; Krahmann, Gerd; Fiedler, Björn; Löscher, Carolin; Grundle, Damian; Hauss, Helena; Körtzinger, Arne; Testor, Pierre; Viera, Nuno</p> <p>2016-04-01</p> <p>The physical (temperature, salinity) and biogeochemical (oxygen, nitrate, chlorophyll fluorescence, turbidity) structure of an anticyclonic modewater eddy, hosting an <span class="hlt">open</span> <span class="hlt">ocean</span> dead zone, is investigated using observational data sampled in high temporal and spatial resolution with autonomous gliders in March and April 2014. The core of the eddy is identified in the glider data as a volume of fresher (on isopycnals) <span class="hlt">water</span> in the depth range from the mixed layer base (about 70m) to about 200m depth. The width is about 80km. The core aligns well with the 40 μmolkg-1 oxygen contour. From two surveys about 1 month apart, changes in the minimal oxygen concentrations (below 5μmolkg-1) are observed that indicate that small scale processes are in operation. Several scales of coherent variability of physical and biogeochemical variable are identified - from a few meters to the mesoscale. One of the gliders carried an autonomous Nitrate (N) sensor and the data is used to analyse the possible nitrogen pathways within the eddy. Also the highest N is accompanied by lowest oxygen concentrations, the AOU:N ratio reveals a preferred oxygen cycling per N.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26684730','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26684730"><span>The symbiotic life of Symbiodinium in the <span class="hlt">open</span> <span class="hlt">ocean</span> within a new species of calcifying ciliate (Tiarina sp.).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mordret, Solenn; Romac, Sarah; Henry, Nicolas; Colin, Sébastien; Carmichael, Margaux; Berney, Cédric; Audic, Stéphane; Richter, Daniel J; Pochon, Xavier; de Vargas, Colomban; Decelle, Johan</p> <p>2016-06-01</p> <p>Symbiotic partnerships between heterotrophic hosts and intracellular microalgae are common in tropical and subtropical oligotrophic <span class="hlt">waters</span> of benthic and pelagic marine habitats. The iconic example is the photosynthetic dinoflagellate genus Symbiodinium that establishes mutualistic symbioses with a wide diversity of benthic hosts, sustaining highly biodiverse reef ecosystems worldwide. Paradoxically, although various species of photosynthetic dinoflagellates are prevalent eukaryotic symbionts in pelagic <span class="hlt">waters</span>, Symbiodinium has not yet been reported in symbiosis within <span class="hlt">oceanic</span> plankton, despite its high propensity for the symbiotic lifestyle. Here we report a new pelagic photosymbiosis between a calcifying ciliate host and the microalga Symbiodinium in surface <span class="hlt">ocean</span> <span class="hlt">waters</span>. Confocal and scanning electron microscopy, together with an 18S rDNA-based phylogeny, showed that the host is a new ciliate species closely related to Tiarina fusus (Colepidae). Phylogenetic analyses of the endosymbionts based on the 28S rDNA gene revealed multiple novel closely related Symbiodinium clade A genotypes. A haplotype network using the high-resolution internal transcribed spacer-2 marker showed that these genotypes form eight divergent, biogeographically structured, subclade types that do not seem to associate with any benthic hosts. Ecological analyses using the Tara <span class="hlt">Oceans</span> metabarcoding data set (V9 region of the 18S rDNA) and contextual oceanographic parameters showed a global distribution of the symbiotic partnership in nutrient-poor surface <span class="hlt">waters</span>. The discovery of the symbiotic life of Symbiodinium in the <span class="hlt">open</span> <span class="hlt">ocean</span> provides new insights into the ecology and evolution of this pivotal microalga and raises new hypotheses about coastal pelagic connectivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5029185','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5029185"><span>The symbiotic life of Symbiodinium in the <span class="hlt">open</span> <span class="hlt">ocean</span> within a new species of calcifying ciliate (Tiarina sp.)</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Mordret, Solenn; Romac, Sarah; Henry, Nicolas; Colin, Sébastien; Carmichael, Margaux; Berney, Cédric; Audic, Stéphane; Richter, Daniel J; Pochon, Xavier; de Vargas, Colomban; Decelle, Johan</p> <p>2016-01-01</p> <p>Symbiotic partnerships between heterotrophic hosts and intracellular microalgae are common in tropical and subtropical oligotrophic <span class="hlt">waters</span> of benthic and pelagic marine habitats. The iconic example is the photosynthetic dinoflagellate genus Symbiodinium that establishes mutualistic symbioses with a wide diversity of benthic hosts, sustaining highly biodiverse reef ecosystems worldwide. Paradoxically, although various species of photosynthetic dinoflagellates are prevalent eukaryotic symbionts in pelagic <span class="hlt">waters</span>, Symbiodinium has not yet been reported in symbiosis within <span class="hlt">oceanic</span> plankton, despite its high propensity for the symbiotic lifestyle. Here we report a new pelagic photosymbiosis between a calcifying ciliate host and the microalga Symbiodinium in surface <span class="hlt">ocean</span> <span class="hlt">waters</span>. Confocal and scanning electron microscopy, together with an 18S rDNA-based phylogeny, showed that the host is a new ciliate species closely related to Tiarina fusus (Colepidae). Phylogenetic analyses of the endosymbionts based on the 28S rDNA gene revealed multiple novel closely related Symbiodinium clade A genotypes. A haplotype network using the high-resolution internal transcribed spacer-2 marker showed that these genotypes form eight divergent, biogeographically structured, subclade types that do not seem to associate with any benthic hosts. Ecological analyses using the Tara <span class="hlt">Oceans</span> metabarcoding data set (V9 region of the 18S rDNA) and contextual oceanographic parameters showed a global distribution of the symbiotic partnership in nutrient-poor surface <span class="hlt">waters</span>. The discovery of the symbiotic life of Symbiodinium in the <span class="hlt">open</span> <span class="hlt">ocean</span> provides new insights into the ecology and evolution of this pivotal microalga and raises new hypotheses about coastal pelagic connectivity. PMID:26684730</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ECSS..184..126W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ECSS..184..126W"><span>Estuarine circulation-driven entrainment of <span class="hlt">oceanic</span> nutrients fuels coastal phytoplankton in an <span class="hlt">open</span> coastal system in Japan</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Watanabe, Kenta; Kasai, Akihide; Fukuzaki, Koji; Ueno, Masahiro; Yamashita, Yoh</p> <p>2017-01-01</p> <p>We investigated interactions among seasonal fluctuations in phytoplankton biomass, riverine nutrient flux, and the fluxes of nutrients entrained by estuarine circulation in Tango Bay, Japan, to determine the influence of freshwater inflows to an <span class="hlt">open</span> bay on coastal phytoplankton productivity. The riverine nutrient flux was strongly regulated by river discharge. Estuarine circulation was driven by river discharge, with high fluxes of nutrients (mean nitrate + nitrite flux: 5.3 ± 3.5 Mg [mega grams]-N day-1) between winter and early spring, enhanced by nutrient supply to the surface <span class="hlt">water</span> via vertical mixing. In contrast, low-nutrient seawater was delivered to the bay between late spring and summer (1.0 ± 0.8 Mg-N day-1). Seasonal fluctuations in phytoplankton biomass were affected by the entrained fluxes of <span class="hlt">oceanic</span> nutrients and variation in the euphotic zone depth, and to a lesser degree by the riverine nutrient flux. Bioassays and stoichiometric analyses indicated that phytoplankton growth was limited by nitrogen and/or phosphorus. Both the entrainment of <span class="hlt">oceanic</span> nutrients and the euphotic zone depth affected the duration and magnitude of blooms. Our findings show that, unlike semi-enclosed bays, seasonal variations in coastal phytoplankton in an <span class="hlt">open</span> coastal system are primarily fueled by the entrainment of <span class="hlt">oceanic</span> nutrients and are influenced by both freshwater inflow and coastal conditions (e.g. vertical mixing and wind events).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMPP12C..07S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMPP12C..07S"><span>Atlantic <span class="hlt">Water</span> Advection and Ice Sheet-<span class="hlt">Ocean</span> Feedbacks in the Arctic <span class="hlt">Ocean</span> During the Last 200 ky</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Spielhagen, R. F.; Mackensen, A.; Stein, R. H.</p> <p>2016-12-01</p> <p>Earlier work on Arctic deep-sea cores from the eastern Lomonosov Ridge and the Morris Jesup Rise had revealed that large-scale Eurasian ice sheet growth was initiated at times with seasonally <span class="hlt">open</span> <span class="hlt">waters</span> in the Arctic <span class="hlt">Ocean</span>, indicating a role for the <span class="hlt">ocean</span> in nearby ice sheet development in the last 200 ky. Here we present microfossil and geochemical data from new sediment cores obtained from the western and easternmost Lomonosov Ridge during the PS87 expedition (2014) of RV Polarstern, amended by data from refined analyses of the older cores. They allow to investigate in more detail the feedbacks between Atlantic <span class="hlt">Water</span> (AW) advection, sea ice, and ice sheets. In all cores, high microfossil abundances are found just below layers rich in iceberg-rafted detritus, supporting the hypothesis of Arctic <span class="hlt">Ocean</span> moisture supply for the growth of Eurasian ice sheets. On the other hand, the new microfaunal results suggest that the decay of the ice sheets and the enhanced freshwater discharge to the Arctic may have influenced the routing of subsurface AW in the Arctic <span class="hlt">Ocean</span>, at least during marine isotope (sub)stages (MIS) 5a and 5e. In the early part of these relatively mild climatic intervals, faunal and isotopic data suggest a noticable advection of Atlantic <span class="hlt">Water</span>, yet of rather low temperature and likely at depths comparable to the modern distribution (i.e., below 150 m) or even deeper. This may be explained by a more southerly position of AW cooling and submergence than today, caused by a thick layer of low saline <span class="hlt">waters</span> near the surface which stemmed from the slow melting of ice sheet remnants on the Eurasian continent and shelves. In the second half of both MIS 5a and 5e, AW advection was significantly stronger and may have occurred at shallower depths, as indicated by unusually large amounts of small subpolar planktic foraminifers in central Arctic sediments. AW was apparently diverted northward from the Fram Strait and spread eastward along the Lomonosov Ridge. A</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA184831','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA184831"><span><span class="hlt">Open-Water</span> Disposal of Material in Canadian <span class="hlt">Waters</span>.</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>1986-01-01</p> <p>P 5.0 COMPARISON OF PUGET SOUND AND CANADIAN REVIEW PROCESSES Technical evaluation procedures for disposal of material in <span class="hlt">open-waters</span> are less...contamination sources 51 V’p ’ p 9U74A ’n C2. CD Z . v*A a 40a 4A %n P .. L 4.0 V L -0 en0 N. =4. La m c .L Azf aa 0%aa - A Li06 0. I 090 %n ow cc 41. S. CL ’A -k...jo.u,.-to, ftitd. aove’ .go.,lce !(@) DESCRIBE CARRIER TRACK( WHILE DUMPING If vpileablIo Oftsiroe 1 L tirlrutanpowteur a. court d. Irmm-sion P . mle</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007SPIE.6680E..02G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007SPIE.6680E..02G"><span>A general <span class="hlt">ocean</span> color atmospheric correction scheme based on principal components analysis: Part I. Performance on Case 1 and Case 2 <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gross-Colzy, Lydwine; Colzy, Stéphane; Frouin, Robert; Henry, Patrice</p> <p>2007-09-01</p> <p>In order to retrieve <span class="hlt">ocean</span> color from satellite imagery, one must perform atmospheric correction, because when observed from space the <span class="hlt">ocean</span> signature is weak compared with the strong atmospheric signal. The color of the <span class="hlt">ocean</span> depends on its optically active constituents: <span class="hlt">water</span> molecules, dissolved matter, and particulate matter. In the <span class="hlt">open</span> <span class="hlt">ocean</span>, the color is mainly due to <span class="hlt">water</span> molecules and phytoplankton, whereas in the coastal zone, the color also results from the presence of sediments and colored dissolved organic matter. Because coastal <span class="hlt">waters</span> (Case 2 <span class="hlt">waters</span>) are much more difficult to decouple from the atmosphere than <span class="hlt">open</span> <span class="hlt">ocean</span> (Case 1 <span class="hlt">waters</span>), operational atmospheric correction algorithms usually separate Case 1 from Case 2 <span class="hlt">waters</span> processing. The solution proposed in this paper does not separate them. Our algorithm, referred to as <span class="hlt">Ocean</span> Color Estimation by principal component ANalysis (<span class="hlt">OCEAN</span>), exploits the fact that <span class="hlt">ocean</span> is more variable spectrally than the atmosphere, while the atmosphere signal is more variable in magnitude. The satellite reflectance is first decomposed into principal components. The components sensitive to the <span class="hlt">ocean</span> signal are then combined to retrieve the principal components of the marine reflectance via neural network methodology. The algorithm is described, and results are presented on real and simulated data for POLDER, MERIS, SeaWiFS, and MODIS. Accurate <span class="hlt">water</span> reflectance estimates are obtained for various aerosol types and contents (including maritime, coastal and urban mixtures), and for the full range of <span class="hlt">water</span> properties (resulting from realistic combinations of chlorophyll content, sediment content, and colored dissolved matter absorption).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989CSR.....9..133T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989CSR.....9..133T"><span><span class="hlt">Ocean</span> optical measurements—II. Statistical analysis of data from Canadian eastern Arctic <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Topliss, B. J.; Miller, J. R.; Horne, E. P. W.</p> <p>1989-02-01</p> <p>The attenuation of light in Arctic <span class="hlt">waters</span> was found to be controlled by chlorophyll pigment and dissolved material with a possible contribution from suspended particulate matter. The potential dependence of the attenuation coefficient on pigment concentration, depth and material type was statistically investigated to evaluate these individual, but intercorrelated, contributions. When the variation of dissolved material with depth was selected as a separation criteria for the intercorrelated in situ variables the statistical analysis suggested a concentration dependence for the specific attenuation coefficient of chlorophyll pigments. A non-linear attenuation/pigment relationship for the Arctic data, governed by concentration and proportion of phaeophytin to chlorophyll, was found to be consistent with clear <span class="hlt">water</span> data from the <span class="hlt">open</span> <span class="hlt">ocean</span> as well as from turbid <span class="hlt">waters</span> on the Grand Banks. Although only approximately 25% of available light was absorbed by chlorophyll a pigment itself, the under-<span class="hlt">water</span> spectrum was modified by these pigments in a manner similar to that occurring in clear <span class="hlt">open</span> <span class="hlt">ocean</span> <span class="hlt">waters</span>. Scattering calculations gave large specific back-scattering values for low pigment concentrations in Arctic <span class="hlt">waters</span> as well as for <span class="hlt">waters</span> from an inshore glacial fjord, posing potential interpretation problems for remote sensing applications. In contrast scattering calculations for high pigment concentrations from the Arctic implied that potentially useful information might be extracted from high latitude imagery.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28618153','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28618153"><span>Cascading influence of inorganic nitrogen sources on DOM production, composition, lability and microbial community structure in the <span class="hlt">open</span> <span class="hlt">ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Goldberg, S J; Nelson, C E; Viviani, D A; Shulse, C N; Church, M J</p> <p>2017-09-01</p> <p>Nitrogen frequently limits <span class="hlt">oceanic</span> photosynthesis and the availability of inorganic nitrogen sources in the surface <span class="hlt">oceans</span> is shifting with global change. We evaluated the potential for abrupt increases in inorganic N sources to induce cascading effects on dissolved organic matter (DOM) and microbial communities in the surface <span class="hlt">ocean</span>. We collected <span class="hlt">water</span> from 5 m depth in the central North Pacific and amended duplicate 20 liter polycarbonate carboys with nitrate or ammonium, tracking planktonic carbon fixation, DOM production, DOM composition and microbial community structure responses over 1 week relative to controls. Both nitrogen sources stimulated bulk phytoplankton, bacterial and DOM production and enriched Synechococcus and Flavobacteriaceae; ammonium enriched for oligotrophic Actinobacteria OM1 and Gammaproteobacteria KI89A clades while nitrate enriched Gammaproteobacteria SAR86, SAR92 and OM60 clades. DOM resulting from both N enrichments was more labile and stimulated growth of copiotrophic Gammaproteobacteria (Alteromonadaceae and Oceanospirillaceae) and Alphaproteobacteria (Rhodobacteraceae and Hyphomonadaceae) in weeklong dark incubations relative to controls. Our study illustrates how nitrogen pulses may have direct and cascading effects on DOM composition and microbial community dynamics in the <span class="hlt">open</span> <span class="hlt">ocean</span>. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28213252','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28213252"><span>Multi-pumping flow system for the determination of boron in eye drops, drinking <span class="hlt">water</span> and <span class="hlt">ocean</span> <span class="hlt">water</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>González, Pablo; Sixto, Alexandra; Knochen, Moisés</p> <p>2017-05-01</p> <p>A novel automated method for the determination of boron based on the use of pulsed flows was developed and applied to the determination of this element in samples of tap <span class="hlt">water</span>, <span class="hlt">ocean</span> <span class="hlt">water</span> and eye drops. The method was implemented by means of a multi-pumping system consisting of three solenoid micropumps and a photometric detector and exploits the reaction of azomethine-H in the presence of boron. The system runs under control of an <span class="hlt">open</span>-source microcontroller. The main operational parameters were optimized. Given the particular kinetics of the reaction, a stopped-flow period (1 or 5min) was included to allow for color development. The method presents linearity in the range 0.35-3.0mgL(-1), good precision (sr<3%), and detection and quantification limits of 0.10 and 0.35mgL(-1) respectively. Samples of tap <span class="hlt">water</span> or eye drops could be successfully analyzed employing a 1-minute stop time, providing a maximum sampling frequency of 32 samples h(-1). In order to overcome matrix effect caused by the high saline concentration, <span class="hlt">ocean</span> <span class="hlt">water</span> samples required stop times of 5min, providing a sampling frequency of 10 samples h(-1). Recoveries of 102% (eye drops), 94% (drinking <span class="hlt">water</span>) and 93% (<span class="hlt">ocean</span> <span class="hlt">water</span>) were obtained. The method was considered accurate and fit for the purpose.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25013074','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25013074"><span><span class="hlt">Ocean</span> microbes. Multispecies diel transcriptional oscillations in <span class="hlt">open</span> <span class="hlt">ocean</span> heterotrophic bacterial assemblages.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ottesen, Elizabeth A; Young, Curtis R; Gifford, Scott M; Eppley, John M; Marin, Roman; Schuster, Stephan C; Scholin, Christopher A; DeLong, Edward F</p> <p>2014-07-11</p> <p>Oscillating diurnal rhythms of gene transcription, metabolic activity, and behavior are found in all three domains of life. However, diel cycles in naturally occurring heterotrophic bacteria and archaea have rarely been observed. Here, we report time-resolved whole-genome transcriptome profiles of multiple, naturally occurring <span class="hlt">oceanic</span> bacterial populations sampled in situ over 3 days. As anticipated, the cyanobacterial transcriptome exhibited pronounced diel periodicity. Unexpectedly, several different heterotrophic bacterioplankton groups also displayed diel cycling in many of their gene transcripts. Furthermore, diel oscillations in different heterotrophic bacterial groups suggested population-specific timing of peak transcript expression in a variety of metabolic gene suites. These staggered multispecies waves of diel gene transcription may influence both the tempo and the mode of matter and energy transformation in the sea.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=238392','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=238392"><span>Identification of resonance waves in <span class="hlt">open</span> <span class="hlt">water</span> channels</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p>This article presents a procedure to determine the characteristics of <span class="hlt">open</span> <span class="hlt">water</span> channels required for controller and filter design, with special focus on the resonance waves. Also, a new simplified model structure for <span class="hlt">open</span> <span class="hlt">water</span> channels is proposed. The procedure applies System Identification tool...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28978724','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28978724"><span>The growth of finfish in global <span class="hlt">open-ocean</span> aquaculture under climate change.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Klinger, Dane H; Levin, Simon A; Watson, James R</p> <p>2017-10-11</p> <p>Aquaculture production is projected to expand from land-based operations to the <span class="hlt">open</span> <span class="hlt">ocean</span> as demand for seafood grows and competition increases for inputs to land-based aquaculture, such as freshwater and suitable land. In contrast to land-based production, <span class="hlt">open-ocean</span> aquaculture is constrained by oceanographic factors, such as current speeds and seawater temperature, which are dynamic in time and space, and cannot easily be controlled. As such, the potential for offshore aquaculture to increase seafood production is tied to the physical state of the <span class="hlt">oceans</span>. We employ a novel spatial model to estimate the potential of <span class="hlt">open-ocean</span> finfish aquaculture globally, given physical, biological and technological constraints. Finfish growth potential for three common aquaculture species representing different thermal guilds-Atlantic salmon (Salmo salar), gilthead seabream (Sparus aurata) and cobia (Rachycentron canadum)-is compared across species and regions and with climate change, based on outputs of a high-resolution global climate model. Globally, there are ample areas that are physically suitable for fish growth and potential expansion of the nascent aquaculture industry. The effects of climate change are heterogeneous across species and regions, but areas with existing aquaculture industries are likely to see increases in growth rates. In areas where climate change results in reduced growth rates, adaptation measures, such as selective breeding, can probably offset potential production losses. © 2017 The Author(s).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1710720W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1710720W"><span>Pathways of Atlantic <span class="hlt">Waters</span> into the Arctic <span class="hlt">Ocean</span>: Eddy-permitting <span class="hlt">ocean</span> and sea ice simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wekerle, Claudia; von Appen, Wilken-Jon; Danilov, Sergey; Jung, Thomas; Kanzow, Torsten; Schauer, Ursula; Timmermann, Ralph; Wang, Qiang</p> <p>2015-04-01</p> <p>Fram Strait is the only deep gateway connecting the central Arctic with the North Atlantic. Boundary currents on each side are responsible for the exchange of <span class="hlt">water</span> masses between the Arctic and North Atlantic. The East Greenland Current (EGC) carries fresh and cold Arctic <span class="hlt">waters</span> and sea ice southward, whereas the West Spitsbergen Current (WSC) carries warm Atlantic <span class="hlt">Waters</span> (AW) into the Arctic <span class="hlt">Ocean</span>. The complex topography in Fram Strait leads to a branching of the northward flowing WSC, with one branch recirculating between 78°N and 81°N which then joins the EGC. To date, the dynamics as well as the precise location of this recirculation are unclear. The goal of this research project is to quantify the amount and variability of AW which recirculates immediately in Fram Strait, and to investigate the role of atmospheric forcing and <span class="hlt">oceanic</span> meso-scale eddies for the recirculation. We use simulations carried out with a global configuration of the Finite Element Sea ice-<span class="hlt">Ocean</span> Model (FESOM) at eddy-permitting scales. The advantage of this model is the finite element discretization of the governing equations, which allows us to locally refine the mesh in areas of interest and keep it coarse in other parts of the global <span class="hlt">oceans</span> without the need for traditional nesting. Here we will show the first results of the model validation. The model has ~9 km resolution in the Nordic Seas and Fram Strait and 1 deg south of 50°N. We assess the model capabilities in simulating the <span class="hlt">ocean</span> circulation in the Nordic Seas and Fram Strait by comparing with the available observational data, e.g. with data from the Fram Strait oceanographic mooring array. The <span class="hlt">ocean</span> volume and heat transport from the Atlantic <span class="hlt">Ocean</span> into the Nordic Seas and at the Fram Strait are analyzed. Our results show that the model can capture some of the observed key <span class="hlt">ocean</span> properties in our region of interest, while some tuning is required to further improve the model. In the next phase of this project we will focus</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ClDy..tmp..359M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ClDy..tmp..359M"><span>Interannual variability of Indian <span class="hlt">Ocean</span> subtropical mode <span class="hlt">water</span> subduction rate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Jie; Lan, Jian</p> <p>2016-08-01</p> <p>The interannual variation of Indian <span class="hlt">Ocean</span> subtropical mode <span class="hlt">water</span> (IOSTMW) subduction rate in the Southwest Indian <span class="hlt">Ocean</span> from 1980 to 2007 is investigated in this paper based on Simple <span class="hlt">Ocean</span> Data Assimilation (SODA) outputs. Climatology of subduction rate exceeds 75 m/year in the IOSTMW formation area. The renewal time of permanent pycnocline <span class="hlt">water</span> mass based on the subduction rate is calculated for each density class: 3-6 years for IOSTMW (25.8 < σ θ < 26.2 kg m-3). Subduction rate in the Southwest Indian <span class="hlt">Ocean</span> subtropical gyre exhibits a great year-to-year variability. This interannual variations of the IOSTMW subduction rate is primarily dominated by the lateral induction term, associated with the interannual variations of strong meridional gradient of winter mixed layer depth (MLD). The slope of the mixed layer depth in the mode <span class="hlt">water</span> is closely linked to the large variations of deep late winter MLD in the mid-latitudes and negligible variations of shallow winter MLD in lower latitudes. It is further identified that the interannual variation of late winter MLD in this area is largely controlled by the latent and sensible heat flux components. The <span class="hlt">water</span> volume of the permanent pycnocline in the IOSTMW distribution area is also found to show a significant interannual variability, and it is well correlated with the interannual variation of subduction rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017ClDy...48.4093M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017ClDy...48.4093M"><span>Interannual variability of Indian <span class="hlt">Ocean</span> subtropical mode <span class="hlt">water</span> subduction rate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ma, Jie; Lan, Jian</p> <p>2017-06-01</p> <p>The interannual variation of Indian <span class="hlt">Ocean</span> subtropical mode <span class="hlt">water</span> (IOSTMW) subduction rate in the Southwest Indian <span class="hlt">Ocean</span> from 1980 to 2007 is investigated in this paper based on Simple <span class="hlt">Ocean</span> Data Assimilation (SODA) outputs. Climatology of subduction rate exceeds 75 m/year in the IOSTMW formation area. The renewal time of permanent pycnocline <span class="hlt">water</span> mass based on the subduction rate is calculated for each density class: 3-6 years for IOSTMW (25.8 < σ θ < 26.2 kg m-3). Subduction rate in the Southwest Indian <span class="hlt">Ocean</span> subtropical gyre exhibits a great year-to-year variability. This interannual variations of the IOSTMW subduction rate is primarily dominated by the lateral induction term, associated with the interannual variations of strong meridional gradient of winter mixed layer depth (MLD). The slope of the mixed layer depth in the mode <span class="hlt">water</span> is closely linked to the large variations of deep late winter MLD in the mid-latitudes and negligible variations of shallow winter MLD in lower latitudes. It is further identified that the interannual variation of late winter MLD in this area is largely controlled by the latent and sensible heat flux components. The <span class="hlt">water</span> volume of the permanent pycnocline in the IOSTMW distribution area is also found to show a significant interannual variability, and it is well correlated with the interannual variation of subduction rate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4538673','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4538673"><span>Decadal acidification in the <span class="hlt">water</span> masses of the Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Ríos, Aida F.; Resplandy, Laure; García-Ibáñez, Maribel I.; Fajar, Noelia M.; Velo, Anton; Padin, Xose A.; Wanninkhof, Rik; Steinfeldt, Reiner; Rosón, Gabriel; Pérez, Fiz F.</p> <p>2015-01-01</p> <p>Global <span class="hlt">ocean</span> acidification is caused primarily by the ocean’s uptake of CO2 as a consequence of increasing atmospheric CO2 levels. We present observations of the <span class="hlt">oceanic</span> decrease in pH at the basin scale (50°S–36°N) for the Atlantic <span class="hlt">Ocean</span> over two decades (1993–2013). Changes in pH associated with the uptake of anthropogenic CO2 (ΔpHCant) and with variations caused by biological activity and <span class="hlt">ocean</span> circulation (ΔpHNat) are evaluated for different <span class="hlt">water</span> masses. Output from an Institut Pierre Simon Laplace climate model is used to place the results into a longer-term perspective and to elucidate the mechanisms responsible for pH change. The largest decreases in pH (∆pH) were observed in central, mode, and intermediate <span class="hlt">waters</span>, with a maximum ΔpH value in South Atlantic Central <span class="hlt">Waters</span> of −0.042 ± 0.003. The ΔpH trended toward zero in deep and bottom <span class="hlt">waters</span>. Observations and model results show that pH changes generally are dominated by the anthropogenic component, which accounts for rates between −0.0015 and −0.0020/y in the central <span class="hlt">waters</span>. The anthropogenic and natural components are of the same order of magnitude and reinforce one another in mode and intermediate <span class="hlt">waters</span> over the time period. Large negative ΔpHNat values observed in mode and intermediate <span class="hlt">waters</span> are driven primarily by changes in CO2 content and are consistent with (i) a poleward shift of the formation region during the positive phase of the Southern Annular Mode in the South Atlantic and (ii) an increase in the rate of the <span class="hlt">water</span> mass formation in the North Atlantic. PMID:26216947</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21185429','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21185429"><span>Modeling the role of nitrification in <span class="hlt">open</span> <span class="hlt">ocean</span> productivity and the nitrogen cycle.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yool, Andrew</p> <p>2011-01-01</p> <p>The <span class="hlt">ocean</span> is an important component of the global carbon cycle, and currently serves as the principal sink for anthropogenic CO(2) from the atmosphere. A key role in the natural <span class="hlt">oceanic</span> carbon cycle is played by the plankton ecosystem, which acts to elevate the storage capacity of the <span class="hlt">ocean</span>, but it is believed that this will experience change in the future in response to anthropogenic forcing. One of the approaches used to understand and forecast the <span class="hlt">oceanic</span> carbon cycle is ecosystem modeling, and this is typically grounded on the nitrogen cycle because of the strong regulatory role this element plays in biological productivity. Nitrification is one of the central processes in the <span class="hlt">oceanic</span> nitrogen cycle, one whose role may change in the future, but also one with a particular relevance to observational efforts to quantify the biological carbon cycle. Here, we describe and summarize current efforts to model nitrification in pelagic <span class="hlt">open</span> <span class="hlt">ocean</span> ecosystems, and look forward to future avenues for progress. Copyright © 2011 Elsevier Inc. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27818853','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27818853"><span>Arctic pathways of Pacific <span class="hlt">Water</span>: Arctic <span class="hlt">Ocean</span> Model Intercomparison experiments.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aksenov, Yevgeny; Karcher, Michael; Proshutinsky, Andrey; Gerdes, Rüdiger; de Cuevas, Beverly; Golubeva, Elena; Kauker, Frank; Nguyen, An T; Platov, Gennady A; Wadley, Martin; Watanabe, Eiji; Coward, Andrew C; Nurser, A J George</p> <p>2016-01-01</p> <p>Pacific <span class="hlt">Water</span> (PW) enters the Arctic <span class="hlt">Ocean</span> through Bering Strait and brings in heat, fresh <span class="hlt">water</span>, and nutrients from the northern Bering Sea. The circulation of PW in the central Arctic <span class="hlt">Ocean</span> is only partially understood due to the lack of observations. In this paper, pathways of PW are investigated using simulations with six state-of-the art regional and global <span class="hlt">Ocean</span> General Circulation Models (OGCMs). In the simulations, PW is tracked by a passive tracer, released in Bering Strait. Simulated PW spreads from the Bering Strait region in three major branches. One of them starts in the Barrow Canyon, bringing PW along the continental slope of Alaska into the Canadian Straits and then into Baffin Bay. The second begins in the vicinity of the Herald Canyon and transports PW along the continental slope of the East Siberian Sea into the Transpolar Drift, and then through Fram Strait and the Greenland Sea. The third branch begins near the Herald Shoal and the central Chukchi shelf and brings PW into the Beaufort Gyre. In the models, the wind, acting via Ekman pumping, drives the seasonal and interannual variability of PW in the Canadian Basin of the Arctic <span class="hlt">Ocean</span>. The wind affects the simulated PW pathways by changing the vertical shear of the relative vorticity of the <span class="hlt">ocean</span> flow in the Canada Basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5070528','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5070528"><span>Arctic pathways of Pacific <span class="hlt">Water</span>: Arctic <span class="hlt">Ocean</span> Model Intercomparison experiments</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Karcher, Michael; Proshutinsky, Andrey; Gerdes, Rüdiger; de Cuevas, Beverly; Golubeva, Elena; Kauker, Frank; Nguyen, An T.; Platov, Gennady A.; Wadley, Martin; Watanabe, Eiji; Coward, Andrew C.; Nurser, A. J. George</p> <p>2016-01-01</p> <p>Abstract Pacific <span class="hlt">Water</span> (PW) enters the Arctic <span class="hlt">Ocean</span> through Bering Strait and brings in heat, fresh <span class="hlt">water</span>, and nutrients from the northern Bering Sea. The circulation of PW in the central Arctic <span class="hlt">Ocean</span> is only partially understood due to the lack of observations. In this paper, pathways of PW are investigated using simulations with six state‐of‐the art regional and global <span class="hlt">Ocean</span> General Circulation Models (OGCMs). In the simulations, PW is tracked by a passive tracer, released in Bering Strait. Simulated PW spreads from the Bering Strait region in three major branches. One of them starts in the Barrow Canyon, bringing PW along the continental slope of Alaska into the Canadian Straits and then into Baffin Bay. The second begins in the vicinity of the Herald Canyon and transports PW along the continental slope of the East Siberian Sea into the Transpolar Drift, and then through Fram Strait and the Greenland Sea. The third branch begins near the Herald Shoal and the central Chukchi shelf and brings PW into the Beaufort Gyre. In the models, the wind, acting via Ekman pumping, drives the seasonal and interannual variability of PW in the Canadian Basin of the Arctic <span class="hlt">Ocean</span>. The wind affects the simulated PW pathways by changing the vertical shear of the relative vorticity of the <span class="hlt">ocean</span> flow in the Canada Basin. PMID:27818853</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JGRC..121...27A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JGRC..121...27A"><span>Arctic pathways of Pacific <span class="hlt">Water</span>: Arctic <span class="hlt">Ocean</span> Model Intercomparison experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Aksenov, Yevgeny; Karcher, Michael; Proshutinsky, Andrey; Gerdes, Rüdiger; de Cuevas, Beverly; Golubeva, Elena; Kauker, Frank; Nguyen, An T.; Platov, Gennady A.; Wadley, Martin; Watanabe, Eiji; Coward, Andrew C.; Nurser, A. J. George</p> <p>2016-01-01</p> <p>Pacific <span class="hlt">Water</span> (PW) enters the Arctic <span class="hlt">Ocean</span> through Bering Strait and brings in heat, fresh <span class="hlt">water</span>, and nutrients from the northern Bering Sea. The circulation of PW in the central Arctic <span class="hlt">Ocean</span> is only partially understood due to the lack of observations. In this paper, pathways of PW are investigated using simulations with six state-of-the art regional and global <span class="hlt">Ocean</span> General Circulation Models (OGCMs). In the simulations, PW is tracked by a passive tracer, released in Bering Strait. Simulated PW spreads from the Bering Strait region in three major branches. One of them starts in the Barrow Canyon, bringing PW along the continental slope of Alaska into the Canadian Straits and then into Baffin Bay. The second begins in the vicinity of the Herald Canyon and transports PW along the continental slope of the East Siberian Sea into the Transpolar Drift, and then through Fram Strait and the Greenland Sea. The third branch begins near the Herald Shoal and the central Chukchi shelf and brings PW into the Beaufort Gyre. In the models, the wind, acting via Ekman pumping, drives the seasonal and interannual variability of PW in the Canadian Basin of the Arctic <span class="hlt">Ocean</span>. The wind affects the simulated PW pathways by changing the vertical shear of the relative vorticity of the <span class="hlt">ocean</span> flow in the Canada Basin.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.7924T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.7924T"><span>Anthropogenic pressure on the <span class="hlt">open</span> <span class="hlt">ocean</span>: The growth of ship traffic revealed by altimeter data analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tournadre, J.</p> <p>2014-11-01</p> <p>Marine ecosystems are under increasing anthropogenic pressures from marine and terrestrial activities. Ship traffic, the major cause of change in the <span class="hlt">open</span> <span class="hlt">ocean</span>, and its temporal evolution are still largely unknown because of lack of data. Altimeter data provide a new powerful tool to detect and monitor the ship traffic through a method of analysis of echo waveform. The archive of seven altimeter missions has been processed to create a two decade database of ship locations. The estimated annual density maps compare well with the ones obtained from Automatic Identification System. The ship traffic analysis shows a global fourfold growth between 1992 and 2012, the largest increase being observed in the Indian <span class="hlt">Ocean</span> and the Chinese seas reflecting the world trade change. Although mainly concentrated along lanes, the traffic has a direct impact on the atmosphere, e.g., on the growth of tropospheric nitrogen dioxide in the Indian <span class="hlt">Ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21719036','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21719036"><span>Organic micropollutants in marine plastics debris from the <span class="hlt">open</span> <span class="hlt">ocean</span> and remote and urban beaches.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hirai, Hisashi; Takada, Hideshige; Ogata, Yuko; Yamashita, Rei; Mizukawa, Kaoruko; Saha, Mahua; Kwan, Charita; Moore, Charles; Gray, Holly; Laursen, Duane; Zettler, Erik R; Farrington, John W; Reddy, Christopher M; Peacock, Emily E; Ward, Marc W</p> <p>2011-08-01</p> <p>To understand the spatial variation in concentrations and compositions of organic micropollutants in marine plastic debris and their sources, we analyzed plastic fragments (∼10 mm) from the <span class="hlt">open</span> <span class="hlt">ocean</span> and from remote and urban beaches. Polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), dichloro-diphenyl-trichloroethane and its metabolites (DDTs), polybrominated diphenyl ethers (PBDEs), alkylphenols and bisphenol A were detected in the fragments at concentrations from 1 to 10,000 ng/g. Concentrations showed large piece-to-piece variability. Hydrophobic organic compounds such as PCBs and PAHs were sorbed from seawater to the plastic fragments. PCBs are most probably derived from legacy pollution. PAHs showed a petrogenic signature, suggesting the sorption of PAHs from oil slicks. Nonylphenol, bisphenol A, and PBDEs came mainly from additives and were detected at high concentrations in some fragments both from remote and urban beaches and the <span class="hlt">open</span> <span class="hlt">ocean</span>. Copyright © 2011 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24718610','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24718610"><span>Impacts of <span class="hlt">ocean</span> acidification on sediment processes in shallow <span class="hlt">waters</span> of the Arctic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gazeau, Frédéric; van Rijswijk, Pieter; Pozzato, Lara; Middelburg, Jack J</p> <p>2014-01-01</p> <p>Despite the important roles of shallow-<span class="hlt">water</span> sediments in global biogeochemical cycling, the effects of <span class="hlt">ocean</span> acidification on sedimentary processes have received relatively little attention. As high-latitude cold <span class="hlt">waters</span> can absorb more CO2 and usually have a lower buffering capacity than warmer <span class="hlt">waters</span>, acidification rates in these areas are faster than those in sub-tropical regions. The present study investigates the effects of <span class="hlt">ocean</span> acidification on sediment composition, processes and sediment-<span class="hlt">water</span> fluxes in an Arctic coastal system. Undisturbed sediment cores, exempt of large dwelling organisms, were collected, incubated for a period of 14 days, and subject to a gradient of pCO2 covering the range of values projected for the end of the century. On five occasions during the experimental period, the sediment cores were isolated for flux measurements (oxygen, alkalinity, dissolved inorganic carbon, ammonium, nitrate, nitrite, phosphate and silicate). At the end of the experimental period, denitrification rates were measured and sediment samples were taken at several depth intervals for solid-phase analyses. Most of the parameters and processes (i.e. mineralization, denitrification) investigated showed no relationship with the overlying seawater pH, suggesting that <span class="hlt">ocean</span> acidification will have limited impacts on the microbial activity and associated sediment-<span class="hlt">water</span> fluxes on Arctic shelves, in the absence of active bio-irrigating organisms. Only following a pH decrease of 1 pH unit, not foreseen in the coming 300 years, significant enhancements of calcium carbonate dissolution and anammox rates were observed. Longer-term experiments on different sediment types are still required to confirm the limited impact of <span class="hlt">ocean</span> acidification on shallow Arctic sediment processes as observed in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3981760','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3981760"><span>Impacts of <span class="hlt">Ocean</span> Acidification on Sediment Processes in Shallow <span class="hlt">Waters</span> of the Arctic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gazeau, Frédéric; van Rijswijk, Pieter; Pozzato, Lara; Middelburg, Jack J.</p> <p>2014-01-01</p> <p>Despite the important roles of shallow-<span class="hlt">water</span> sediments in global biogeochemical cycling, the effects of <span class="hlt">ocean</span> acidification on sedimentary processes have received relatively little attention. As high-latitude cold <span class="hlt">waters</span> can absorb more CO2 and usually have a lower buffering capacity than warmer <span class="hlt">waters</span>, acidification rates in these areas are faster than those in sub-tropical regions. The present study investigates the effects of <span class="hlt">ocean</span> acidification on sediment composition, processes and sediment-<span class="hlt">water</span> fluxes in an Arctic coastal system. Undisturbed sediment cores, exempt of large dwelling organisms, were collected, incubated for a period of 14 days, and subject to a gradient of pCO2 covering the range of values projected for the end of the century. On five occasions during the experimental period, the sediment cores were isolated for flux measurements (oxygen, alkalinity, dissolved inorganic carbon, ammonium, nitrate, nitrite, phosphate and silicate). At the end of the experimental period, denitrification rates were measured and sediment samples were taken at several depth intervals for solid-phase analyses. Most of the parameters and processes (i.e. mineralization, denitrification) investigated showed no relationship with the overlying seawater pH, suggesting that <span class="hlt">ocean</span> acidification will have limited impacts on the microbial activity and associated sediment-<span class="hlt">water</span> fluxes on Arctic shelves, in the absence of active bio-irrigating organisms. Only following a pH decrease of 1 pH unit, not foreseen in the coming 300 years, significant enhancements of calcium carbonate dissolution and anammox rates were observed. Longer-term experiments on different sediment types are still required to confirm the limited impact of <span class="hlt">ocean</span> acidification on shallow Arctic sediment processes as observed in this study. PMID:24718610</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3683730','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3683730"><span>Polaro–cryptic mirror of the lookdown as a biological model for <span class="hlt">open</span> <span class="hlt">ocean</span> camouflage</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Brady, Parrish C.; Travis, Kort A.; Maginnis, Tara; Cummings, Molly E.</p> <p>2013-01-01</p> <p>With no object to hide behind in 3D space, the <span class="hlt">open</span> <span class="hlt">ocean</span> represents a challenging environment for camouflage. Conventional strategies for reflective crypsis (e.g., standard mirror) are effective against axially symmetric radiance fields associated with high solar altitudes, yet ineffective against asymmetric polarized radiance fields associated with low solar inclinations. Here we identify a biological model for polaro–crypsis. We measured the surface-reflectance Mueller matrix of live <span class="hlt">open</span> <span class="hlt">ocean</span> fish (lookdown, Selene vomer) and seagrass-dwelling fish (pinfish, Lagodon rhomboides) using polarization-imaging and modeling polarization camouflage for the <span class="hlt">open</span> <span class="hlt">ocean</span>. Lookdowns occupy the minimization basin of our polarization-contrast space, while pinfish and standard mirror measurements exhibit higher contrast values than optimal. The lookdown reflective strategy achieves significant gains in polaro–crypsis (up to 80%) in comparison with nonpolarization sensitive strategies, such as a vertical mirror. Lookdowns achieve polaro–crypsis across solar altitudes by varying reflective properties (described by 16 Mueller matrix elements mij) with incident illumination. Lookdowns preserve reflected polarization aligned with principle axes (dorsal–ventral and anterior–posterior, m22 = 0.64), while randomizing incident polarization 45° from principle axes (m33 = –0.05). These reflectance properties allow lookdowns to reflect the uniform degree and angle of polarization associated with high-noon conditions due to alignment of the principle axes and the sun, and reflect a more complex polarization pattern at asymmetrical light fields associated with lower solar elevations. Our results suggest that polaro–cryptic strategies vary by habitat, and require context-specific depolarization and angle alteration for effective concealment in the complex <span class="hlt">open</span> <span class="hlt">ocean</span> environment. PMID:23716701</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ACP.....9.9635R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ACP.....9.9635R"><span>On the representativeness of coastal aerosol studies to <span class="hlt">open</span> <span class="hlt">ocean</span> studies: Mace Head - a case study</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rinaldi, M.; Facchini, M. C.; Decesari, S.; Carbone, C.; Finessi, E.; Mircea, M.; Fuzzi, S.; Ceburnis, D.; Ehn, M.; Kulmala, M.; de Leeuw, G.; O'Dowd, C. D.</p> <p>2009-12-01</p> <p>A unique opportunity arose during the MAP project to compare <span class="hlt">open</span> <span class="hlt">ocean</span> aerosol measurements with those undertaken at the Mace Head Global Atmosphere Watch Station, a station used for decades for aerosol process research and long-term monitoring. The objective of the present study is to demonstrate that the key aerosol features and processes observed at Mace Head are characteristic of the <span class="hlt">open</span> <span class="hlt">ocean</span>, while acknowledging and allowing for spatial and temporal gradients. Measurements were conducted for a 5-week period at Mace Head and offshore, on the Research Vessel Celtic Explorer, in generally similar marine air masses, albeit not in connected-flow scenarios. The results of the study indicate, in terms of aerosol number size distribution, higher nucleation mode particle concentrations at Mace Head than offshore, pointing to a strong coastal source of new particles that is not representative of the <span class="hlt">open</span> <span class="hlt">ocean</span>. The Aitken mode exhibited a large degree of similarity, with no systematic differences between Mace Head and the <span class="hlt">open</span> <span class="hlt">ocean</span>, while the accumulation mode showed averagely 35% higher concentrations at Mace Head. The higher accumulation mode concentration can be attributed equally to cloud processing and to a coastal enhancement in concentration. Chemical analysis showed similar or even higher offshore concentrations for dominant species, such as nss-SO4-2, WSOC, WIOC and MSA. Sea salt concentration differences determined a 40% higher supermicron mass at Mace Head, although this difference can be attributed to a higher wind speed at Mace Head during the comparison period. Moreover, the relative chemical composition as a function of size illustrated remarkable similarity. While differences to varying degrees were observed between offshore and coastal measurements, no convincing evidence was found of local coastal effects, apart from nucleation mode aerosol, thus confirming the integrity of previously reported marine aerosol characterisation studies at Mace Head.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS31B1717B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS31B1717B"><span>Evidence for <span class="hlt">Open-Ocean</span> Atmospheric Deposition of Lignin as a Significant Source of Chromophoric Dissolved Organic Matter in the North Atlantic Subtropical Gyre</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bocarsly, J. D.; McDonald, N.; Peters, A.; Nelson, N. B.</p> <p>2012-12-01</p> <p>Chromophoric dissolved organic matter (CDOM) has been studied extensively for its role in shaping the <span class="hlt">oceanic</span> underwater light field. While much is understood about the chemical composition and properties of coastal CDOM, its source, composition, fate and transport in the <span class="hlt">open</span> <span class="hlt">ocean</span> remain relatively unknown. Notably, data from the last decade suggest that <span class="hlt">water</span> mass movement and resuspension and horizontal transport of sediments alone are not enough to account for the presence of terrestrial-source CDOM in the <span class="hlt">open</span> <span class="hlt">ocean</span>. In this study, we investigated atmospheric deposition as a potential source of terrestrial CDOM in the <span class="hlt">open</span> <span class="hlt">ocean</span>. Lignin, a polymer found only in vascular plants, served as a tracer for terrestrially derived CDOM. Selected individual lignin phenols were quantified in aerosol and seawater samples using GC-MS analysis. In addition to quantitative data, ratios of the concentrations of these methoxy phenols give qualitative information about the source and degree of photodegradation of the source lignin. A high volume air sampler (2.88m3/min) was used to sample aerosol particles <10 μm in diameter at the Bermuda Atlantic Time Series site (31 40.00 N, 64 10.00 W), in the Sargasso Sea. Concurrently, <span class="hlt">water</span> samples were collected from the <span class="hlt">ocean</span> surface, local bacterial maximum, and deep chlorophyll maximum. In addition, samples of Sargassum macroalgae as well as particulate organic matter were collected to study potential additional sources of <span class="hlt">open</span> <span class="hlt">ocean</span> surface CDOM. Consistently, lignin phenols were present in the aerosol samples and their relative concentrations resembled those of the lignin phenols detected in surface <span class="hlt">water</span>. The aerosol lignin phenol composition did not, on the other hand, resemble that found in deeper <span class="hlt">ocean</span> <span class="hlt">water</span>. Low levels of sodium ion quantified via ion chromatography in the aerosol samples demonstrate that seawater from sea spray is not a significant source of the sampled aerosol. These results suggest that atmospheric</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770059878&hterms=wakefield&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwakefield','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770059878&hterms=wakefield&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dwakefield"><span>Experimental remote sensing of subsurface temperature in natural <span class="hlt">ocean</span> <span class="hlt">water</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leonard, D. A.; Caputo, B.; Johnson, R. L.; Hoge, F. E.</p> <p>1977-01-01</p> <p>The first successful depth-resolved remote sensing measurements of subsurface <span class="hlt">ocean</span> <span class="hlt">water</span> temperature were obtained by spectral analysis of the 3400 per cm O-H stretching Raman band of liquid <span class="hlt">water</span>. Raman spectral data were obtained from a research vessel at various depths from the surface to 10 meters below the surface in a tidal estuary. The temperature inferred from the spectra was consistent with ground truth temperature to within the shot noise limited accuracy of plus or minus 2 C. The performance of a future fully developed airborne laser Raman <span class="hlt">water</span> temperature measurement system is estimated on the basis of these first tests.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19770059878&hterms=water+temperature&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwater%2Btemperature','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19770059878&hterms=water+temperature&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dwater%2Btemperature"><span>Experimental remote sensing of subsurface temperature in natural <span class="hlt">ocean</span> <span class="hlt">water</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leonard, D. A.; Caputo, B.; Johnson, R. L.; Hoge, F. E.</p> <p>1977-01-01</p> <p>The first successful depth-resolved remote sensing measurements of subsurface <span class="hlt">ocean</span> <span class="hlt">water</span> temperature were obtained by spectral analysis of the 3400 per cm O-H stretching Raman band of liquid <span class="hlt">water</span>. Raman spectral data were obtained from a research vessel at various depths from the surface to 10 meters below the surface in a tidal estuary. The temperature inferred from the spectra was consistent with ground truth temperature to within the shot noise limited accuracy of plus or minus 2 C. The performance of a future fully developed airborne laser Raman <span class="hlt">water</span> temperature measurement system is estimated on the basis of these first tests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011E%26PSL.311..264D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011E%26PSL.311..264D"><span>Molybdenum evidence for expansive sulfidic <span class="hlt">water</span> masses in ~ 750 Ma <span class="hlt">oceans</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dahl, Tais W.; Canfield, Donald E.; Rosing, Minik T.; Frei, Robert E.; Gordon, Gwyneth W.; Knoll, Andrew H.; Anbar, Ariel D.</p> <p>2011-11-01</p> <p>The Ediacaran appearance of large animals, including motile bilaterians, is commonly hypothesized to reflect a physiologically enabling increase in atmospheric and <span class="hlt">oceanic</span> oxygen abundances (pO 2). To date, direct evidence for low oxygen in pre-Ediacaran <span class="hlt">oceans</span> has focused on chemical signatures in the rock record that reflect conditions in local basins, but this approach is both biased to constrain only shallower basins and statistically limited when we seek to follow the evolution of mean <span class="hlt">ocean</span> chemical state through time. Because the abundance and isotopic composition of molybdenum (Mo) in organic-rich euxinic sediments can vary in response to changes in global redox conditions, Mo geochemistry provides independent constraints on the global evolution of well-oxygenated environments. Here, we establish a theoretical framework to access global marine Mo cycle in the past from the abundance and isotope composition of ancient seawater. Further, we investigate the ~ 750 Ma Walcott Member of the Chuar Group, Grand Canyon, which accumulated in a rift basin with <span class="hlt">open</span> connection to the <span class="hlt">ocean</span>. Iron speciation data from upper Walcott shales indicate that local bottom <span class="hlt">waters</span> were anoxic and sulfidic, consistent with their high organic content (up to 20 wt.%). Similar facies in Phanerozoic successions contain high concentrations of redox-sensitive metals, but in the Walcott Member, abundances of Mo and U, as well as Mo/TOC (~ 0.5 ppm/wt.%) are low. δ 98Mo values also fall well below modern equivalents (0.99 ± 0.13‰ versus ~ 2.35‰ today). These signatures are consistent with model predictions where sulfidic <span class="hlt">waters</span> cover ~ 1-4% of the global seafloor, corresponding to a ~ 20-80 fold increase compared to the modern <span class="hlt">ocean</span>. Therefore, our results suggest globally expansive sulfidic <span class="hlt">water</span> masses in mid-Neoproterozoic <span class="hlt">oceans</span>, bridging a nearly 700 million-year gap in previous Mo data. We propose that anoxic and sulfidic (euxinic) conditions governed Mo cycling in the <span class="hlt">oceans</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26691595','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26691595"><span>Resilience of SAR11 bacteria to rapid acidification in the high-latitude <span class="hlt">open</span> <span class="hlt">ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hartmann, Manuela; Hill, Polly G; Tynan, Eithne; Achterberg, Eric P; Leakey, Raymond J G; Zubkov, Mikhail V</p> <p>2016-02-01</p> <p>Ubiquitous SAR11 Alphaproteobacteria numerically dominate marine planktonic communities. Because they are excruciatingly difficult to cultivate, there is comparatively little known about their physiology and metabolic responses to long- and short-term environmental changes. As surface <span class="hlt">oceans</span> take up anthropogenic, atmospheric CO2, the consequential process of <span class="hlt">ocean</span> acidification could affect the global biogeochemical significance of SAR11. Shipping accidents or inadvertent release of chemicals from industrial plants can have strong short-term local effects on <span class="hlt">oceanic</span> SAR11. This study investigated the effect of 2.5-fold acidification of seawater on the metabolism of SAR11 and other heterotrophic bacterioplankton along a natural temperature gradient crossing the North Atlantic <span class="hlt">Ocean</span>, Norwegian and Greenland Seas. Uptake rates of the amino acid leucine by SAR11 cells as well as other bacterioplankton remained similar to controls despite an instant ∼50% increase in leucine bioavailability upon acidification. This high physiological resilience to acidification even without acclimation, suggests that <span class="hlt">open</span> <span class="hlt">ocean</span> dominant bacterioplankton are able to cope even with sudden and therefore more likely with long-term acidification effects. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GPC...123..152M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GPC...123..152M"><span>A model of <span class="hlt">oceanic</span> development by ridge jumping: <span class="hlt">Opening</span> of the Scotia Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Maldonado, Andrés; Bohoyo, Fernando; Galindo-Zaldívar, Jesús; Hernández-Molina, Fº. Javier; Lobo, Francisco J.; Lodolo, Emanuele; Martos, Yasmina M.; Pérez, Lara F.; Schreider, Anatoly A.; Somoza, Luis</p> <p>2014-12-01</p> <p>Ona Basin is a small intra-<span class="hlt">oceanic</span> basin located in the southwestern corner of the Scotia Sea. This region is crucial for an understanding of the early phases of <span class="hlt">opening</span> of Drake Passage, since it may contain the oldest <span class="hlt">oceanic</span> crust of the entire western Scotia Sea, where conflicting age differences from Eocene to Oligocene have been proposed to date. The precise timing of the gateway <span class="hlt">opening</span> between the Pacific and Atlantic <span class="hlt">oceans</span>, moreover, has significant paleoceanographic and global implications. Two sub-basins are identified in this region, the eastern and western Ona basins, separated by the submarine relief of the Ona High. A dense geophysical data set collected during the last two decades is analyzed here. The data include multichannel seismic reflection profiles, and magnetic and gravimetric data. The <span class="hlt">oceanic</span> basement is highly deformed by normal, reverse and transcurrent faults, as well as affected by deep intrusions from the mantle. The initial extension and continental thinning, with subsequent <span class="hlt">oceanic</span> spreading, were followed by compression and thrusting. Several elongated troughs, bounded by faults, depict a thick sequence of depositional units in the basin. Eight seismic units are identified in a deep trough of the eastern Ona Basin. The deposits reach a thickness of 5 km, a consistent value not previously reported from the Scotia Sea. A body of chaotic seismic facies is also observed above the thinned continental crust of the Ona High. Magnetic seafloor anomalies older than C10 (~ 28.5 Ma) may be present in the region. The anomalies could include up to chron C12r (~ 32 Ma), although their identification is difficult, since the amplitude is subdued and the original <span class="hlt">oceanic</span> crust was highly deformed by later faulting and thrusting. The magnetic anomaly distribution is not congruent with seafloor spreading from a single ridge. The basin plain is tilted and subducted southwestward below the South Shetland Islands Block, particularly in the western part</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3583772','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3583772"><span>Deep <span class="hlt">ocean</span> mineral <span class="hlt">water</span> accelerates recovery from physical fatigue</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p></p> <p>2013-01-01</p> <p>Background Deep <span class="hlt">oceans</span> have been suggested as a possible site where the origin of life occurred. Along with this theoretical lineage, experiments using components from deep <span class="hlt">ocean</span> <span class="hlt">water</span> to recreate life is underway. Here, we propose that if terrestrial organisms indeed evolved from deep <span class="hlt">oceans</span>, supply of deep <span class="hlt">ocean</span> mineral <span class="hlt">water</span> (DOM) to humans, as a land creature, may replenish loss of molecular complexity associated with evolutionary sea-to-land migration. Methods We conducted a randomized, double-blind, placebo-controlled crossover human study to evaluate the effect of DOM, taken from a depth of 662 meters off the coast of Hualien, Taiwan, on time of recovery from a fatiguing exercise conducted at 30°C. Results The fatiguing exercise protocol caused a protracted reduction in aerobic power (reduced VO2max) for 48 h. However, DOM supplementation resulted in complete recovery of aerobic power within 4 h (P < 0.05). Muscle power was also elevated above placebo levels within 24 h of recovery (P < 0.05). Increased circulating creatine kinase (CK) and myoglobin, indicatives of exercise-induced muscle damage, were completely eliminated by DOM (P < 0.05) in parallel with attenuated oxidative damage (P < 0.05). Conclusion Our results provide compelling evidence that DOM contains soluble elements, which can increase human recovery following an exhaustive physical challenge. PMID:23402436</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23402436','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23402436"><span>Deep <span class="hlt">ocean</span> mineral <span class="hlt">water</span> accelerates recovery from physical fatigue.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hou, Chien-Wen; Tsai, Yung-Shen; Jean, Wei-Horng; Chen, Chung-Yu; Ivy, John L; Huang, Chih-Yang; Kuo, Chia-Hua</p> <p>2013-02-12</p> <p>Deep <span class="hlt">oceans</span> have been suggested as a possible site where the origin of life occurred. Along with this theoretical lineage, experiments using components from deep <span class="hlt">ocean</span> <span class="hlt">water</span> to recreate life is underway. Here, we propose that if terrestrial organisms indeed evolved from deep <span class="hlt">oceans</span>, supply of deep <span class="hlt">ocean</span> mineral <span class="hlt">water</span> (DOM) to humans, as a land creature, may replenish loss of molecular complexity associated with evolutionary sea-to-land migration. We conducted a randomized, double-blind, placebo-controlled crossover human study to evaluate the effect of DOM, taken from a depth of 662 meters off the coast of Hualien, Taiwan, on time of recovery from a fatiguing exercise conducted at 30°C. The fatiguing exercise protocol caused a protracted reduction in aerobic power (reduced VO2max) for 48 h. However, DOM supplementation resulted in complete recovery of aerobic power within 4 h (P < 0.05). Muscle power was also elevated above placebo levels within 24 h of recovery (P < 0.05). Increased circulating creatine kinase (CK) and myoglobin, indicatives of exercise-induced muscle damage, were completely eliminated by DOM (P < 0.05) in parallel with attenuated oxidative damage (P < 0.05). Our results provide compelling evidence that DOM contains soluble elements, which can increase human recovery following an exhaustive physical challenge.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSHE21A..05S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSHE21A..05S"><span>The Role of Late Summer Melt Pond <span class="hlt">Water</span> Layers in the <span class="hlt">Ocean</span> Mixed Layer on Enhancing Ice/<span class="hlt">Ocean</span> Albedo Feedbacks in the Arctic</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stanton, T. P.; Shaw, W. J.</p> <p>2016-02-01</p> <p>Drainage of surface melt pond <span class="hlt">water</span> into the top of the <span class="hlt">ocean</span> mixed layer is seen widely in the Arctic ice pack in later summer (for example Gallaher et al 2015). Under calm conditions, this fresh <span class="hlt">water</span> forms a thin, stratified layer immediately below the ice which is dynamically decoupled from the thicker, underlying seasonal mixed layer by the density difference between the two layers. The ephemeral surface layer is significantly warmer than the underlying <span class="hlt">ocean</span> <span class="hlt">water</span> owing to the higher freezing temperature of the fresh melt <span class="hlt">water</span>. How the presence of this warm ephemeral layer enhances basal melt rate and speeds the destruction of the floes is investigated. High resolution timeseries measurements of T/S profiles in the 2m of the <span class="hlt">ocean</span> immediately below the ice, and eddy-correlation fluxes of heat, salt and momentum 2.5m below the ice were made from an Autonomous <span class="hlt">Ocean</span> Flux Buoy over a 2 month interval in later summer of 2015 as a component of the ONR Marginal Ice Zone project. The stratification and turbulent forcing observations are used with a 1 D turbulence closure model to understand how momentum and incoming radiative energy are stored and redistributed within the ephemeral layer. Under low wind forcing conditions both turbulent mixing energy and the <span class="hlt">water</span> with high departure from freezing are trapped in the ephemeral layer by the strong density gradient at the base of the layer, resulting in rapid basal melting. This case is contrasted with model runs where the ephemeral layer heat is allowed to mix across the seasonal mixed layer, which results in slower basal melt rates. Consequently, the salinity-trapped warm ephemeral layer results in the formation of more <span class="hlt">open</span> <span class="hlt">water</span> earlier in the summer season, in turn resulting in increased cumulative heating of the <span class="hlt">ocean</span> mixed layer, enhancing ice/<span class="hlt">ocean</span> albedo feedbacks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMPP51B2112W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMPP51B2112W"><span>Constraints on the sources of branched GDGTs in <span class="hlt">open</span> <span class="hlt">ocean</span> sediments: dust transport or in situ production?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Weijers, J.; Schefuss, E.; Kim, J.; Sinninghe Damsté, J. S.; Schouten, S.</p> <p>2012-12-01</p> <p>Branched glycerol dialkyl glycerol tetraethers (brGDGTs) are membrane lipids synthesized by soil bacteria that, upon soil erosion, are transported by rivers to the <span class="hlt">ocean</span> where they accumulate in the near shore sedimentary archive. The degrees of cyclisation (CBT) and methylation (MBT) of these compounds have been shown to relate to soil pH and annual mean air temperature [1]. Therefore, brGDGTs in near shore sedimentary archives can be used to estimate past continental air temperatures and enable a direct comparison of these to marine sea surface temperature estimates obtained from the same samples. In addition, brGDGT abundance relative to crenarchaeol, an isoprenoid GDGT synthesized by marine pelagic Thaumarchaeota, quantified in the branched vs. isoprenoid tetraether (BIT) index, is an indicator of the relative input of soil organic matter in near shore sediments [2]. High BIT values near river outflows testify of relative strong soil organic matter input and generally the BIT index will decrease off shore to values near 0, the marine end-member value. Even in remote <span class="hlt">open</span> <span class="hlt">ocean</span> sediments, however, the BIT index will rarely reach 0 as small amounts of brGDGTs are often present. The occurrence of these brGDGTs in <span class="hlt">open</span> marine settings might be a result of i) dust input, ii) sediment dispersion from near coastal areas, or iii) in situ production in marine sediments. In order to constrain the origin of branched GDGTs in <span class="hlt">open</span> marine sediments we analyzed i) atmospheric dust samples taken along an equatorial African coastal transect, ii) marine surface <span class="hlt">waters</span> near and away of the Congo river outflow, iii) a series of surface sediments at and around the Congo deep sea fan, and iv) a series of <span class="hlt">open</span> marine surface sediments from different <span class="hlt">oceans</span> with BIT values < 0.08. Our results show that brGDGTs are present, though in relative low amounts, in dust. Their distribution resembles that of soil input as also found in the Congo deep sea fan, with MBT and CBT values that</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1338761-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1338761-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model"><span>Local atmospheric response to an <span class="hlt">open-ocean</span> polynya in a high-resolution climate model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Weijer, Wilbert; Veneziani, Milena; Stössel, Achim; ...</p> <p>2016-11-17</p> <p>For this scientific paper, we study the atmospheric response to an <span class="hlt">open-ocean</span> polynya in the Southern <span class="hlt">Ocean</span> by analyzing the results from an atmospheric and <span class="hlt">oceanic</span> synoptic-scale resolving Community Earth System Model (CESM) simulation. While coarser-resolution versions of CESM generally do not produce <span class="hlt">open-ocean</span> polynyas in the Southern <span class="hlt">Ocean</span>, they do emerge and disappear on interannual timescales in the synoptic-scale simulation. This provides an ideal opportunity to study the polynya’s impact on the overlying and surrounding atmosphere. This has been pursued here by investigating the seasonal cycle of differences of surface and air-column variables between polynya and non-polynya years. Ourmore » results indicate significant local impacts on turbulent heat fluxes, precipitation, cloud characteristics, and radiative fluxes. In particular, we find that clouds over polynyas are optically thicker and higher than clouds over sea ice during non-polynya years. Although the lower albedo of polynyas significantly increases the net shortwave absorption, the enhanced cloud brightness tempers this increase by almost 50%. Also, in this model, enhanced longwave radiation emitted from the warmer surface of polynyas is balanced by stronger downwelling fluxes from the thicker cloud deck. Impacts are found to be sensitive to the synoptic wind direction. Strongest regional impacts are found when northeasterly winds cross the polynya and interact with katabatic winds. Finally, surface air pressure anomalies over the polynya are only found to be significant when cold, dry air masses strike over the polynya, i.e. in case of southerly winds.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000120582&hterms=many+oceans+world&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmany%2Boceans%2Bworld','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000120582&hterms=many+oceans+world&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dmany%2Boceans%2Bworld"><span>Global Distribution of Aerosols Over the <span class="hlt">Open</span> <span class="hlt">Ocean</span> as Derived from the Coastal Zone Color Scanner</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Stegmann, P. M.; Tindale, N. W.</p> <p>1999-01-01</p> <p>Climatological maps of monthly mean aerosol radiance levels derived from the coastal zone color scanner (CZCS) were constructed for the world's <span class="hlt">ocean</span> basins. This is the first study to use the 7.5.-year CZCS data set to examine the distribution and seasonality of aerosols over the <span class="hlt">open</span> <span class="hlt">ocean</span> on a global scale. Examination of our satellite images found the most prominent large-scale patch of elevated aerosol radiances in each month off the coast of northwest Africa. The well-known, large-scale plumes of elevated aerosol levels in the Arabian Sea, the northwest Pacific, and off the east coast of North America were also successfully captured. Radiance data were extracted from 13 major <span class="hlt">open-ocean</span> zones, ranging from the subpolar to equatorial regions. Results from these extractions revealed the aerosol load in both subpolar and subtropical zones to be higher in the Northern Hemisphere than in the Southern Hemisphere. Aerosol radiances in the subtropics of both hemispheres were about 2 times higher in summer than in winter. In subpolar regions, aerosol radiances in late spring/early summer were almost 3 times that observed in winter. In general, the aerosol signal was higher during the warmer months and lower during the cooler months, irrespective of location. A comparison between our mean monthly aerosol radiance maps with mean monthly chlorophyll maps (also from CZCS) showed similar seasonality between aerosol and chlorophyll levels in the subpolar zones of both hemispheres, i.e., high levels in summer, low levels in winter. In the subtropics of both hemispheres, however, chlorophyll levels were higher in winter months which coincided with a depressed aerosol signal. Our results indicate that the near-IR channel on <span class="hlt">ocean</span> color sensors can be used to successfully capture well-known, large-scale aerosol plumes on a global scale and that future <span class="hlt">ocean</span> color sensors may provide a platform for long-term synoptic studies of combined aerosol-phytoplankton productivity</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ECSS...85..223P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ECSS...85..223P"><span>Distributions of dissolved vitamin B 12 and Co in coastal and <span class="hlt">open-ocean</span> environments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Panzeca, Caterina; Beck, Aaron J.; Tovar-Sanchez, Antonio; Segovia-Zavala, Jose; Taylor, Gordon T.; Gobler, Christopher J.; Sañudo-Wilhelmy, Sergio A.</p> <p>2009-11-01</p> <p>Distributions of dissolved vitamin B 12 and total dissolved Co were measured to gain an understanding of the cycling of these interdependent micronutrients in six marine settings including; an upwelling location, a semi-enclosed bay, two urban coastal systems, and two <span class="hlt">open</span> <span class="hlt">ocean</span> locations. Along the coast of Baja California, Mexico, concentrations of B 12 and dissolved Co varied from 0.2 to 11 pM and 180 to 990 pM, respectively. At a nearby upwelling station, vitamin B 12 and Co concentrations ranged from 0.3 to 7.0 pM and 22 to 145 pM, and concentrations did not correlate with upwelling intensity. Concentrations of B 12 were highest within Todos Santos Bay, a semi-enclosed bay off the coast of Baja California, Mexico, during a dinoflagellate bloom, ranging from 2 to 61 pM, while Co concentrations varied between 61 and 194 pM. In the anthropogenically impacted Long Island Sound, NY, U.S.A., B 12 levels were between 0.1 and 23 pM and Co concentrations varied from 60 to 1900 pM. However, anthropogenic inputs were not evident in B 12 levels in the San Pedro Basin, located outside Los Angeles, Ca, U.S.A., where concentrations of B 12 were 0.2-1.8 pM, approximating observed <span class="hlt">open</span> <span class="hlt">ocean</span> B 12 concentrations. In the Southern <span class="hlt">Ocean</span> and North Atlantic <span class="hlt">Ocean</span>, B 12 levels were 0.4-4 pM and 0.2-2 pM, respectively. Total Co concentrations in the Southern <span class="hlt">Ocean</span> and North Atlantic tended to be low; measuring 26-59 pM and 15-80 pM, respectively. These low Co concentrations may limit B 12 synthesis and its availability to B 12-requiring phytoplankton because the total dissolved Co pool is not necessarily entirely bioavailable.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1343648-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1343648-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model"><span>Local Atmospheric Response to an <span class="hlt">Open-Ocean</span> Polynya in a High-Resolution Climate Model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Weijer, Wilbert; Veneziani, Milena; Stössel, Achim; ...</p> <p>2017-03-01</p> <p>For this scientific paper, we study the atmospheric response to an <span class="hlt">open-ocean</span> polynya in the Southern <span class="hlt">Ocean</span> by analyzing the results from an atmospheric and <span class="hlt">oceanic</span> synoptic-scale resolving Community Earth System Model (CESM) simulation. While coarser-resolution versions of CESM generally do not produce <span class="hlt">open-ocean</span> polynyas in the Southern <span class="hlt">Ocean</span>, they do emerge and disappear on interannual timescales in the synoptic-scale simulation. This provides an ideal opportunity to study the polynya’s impact on the overlying and surrounding atmosphere. This has been pursued here by investigating the seasonal cycle of differences of surface and air-column variables between polynya and non-polynya years. Ourmore » results indicate significant local impacts on turbulent heat fluxes, precipitation, cloud characteristics, and radiative fluxes. In particular, we find that clouds over polynyas are optically thicker and higher than clouds over sea ice during non-polynya years. Although the lower albedo of polynyas significantly increases the net shortwave absorption, the enhanced cloud brightness tempers this increase by almost 50%. Also, in this model, enhanced longwave radiation emitted from the warmer surface of polynyas is balanced by stronger downwelling fluxes from the thicker cloud deck. Impacts are found to be sensitive to the synoptic wind direction. Strongest regional impacts are found when northeasterly winds cross the polynya and interact with katabatic winds. Finally, surface air pressure anomalies over the polynya are only found to be significant when cold, dry air masses strike over the polynya, i.e. in case of southerly winds.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/pages/biblio/1346290-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model','SCIGOV-DOEP'); return false;" href="https://www.osti.gov/pages/biblio/1346290-local-atmospheric-response-open-ocean-polynya-high-resolution-climate-model"><span>Local Atmospheric Response to an <span class="hlt">Open-Ocean</span> Polynya in a High-Resolution Climate Model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/pages">DOE PAGES</a></p> <p>Weijer, Wilbert; Veneziani, Milena; Stössel, Achim; ...</p> <p>2017-03-01</p> <p>For this scientific paper, we study the atmospheric response to an <span class="hlt">open-ocean</span> polynya in the Southern <span class="hlt">Ocean</span> by analyzing the results from an atmospheric and <span class="hlt">oceanic</span> synoptic-scale resolving Community Earth System Model (CESM) simulation. While coarser-resolution versions of CESM generally do not produce <span class="hlt">open-ocean</span> polynyas in the Southern <span class="hlt">Ocean</span>, they do emerge and disappear on interannual timescales in the synoptic-scale simulation. This provides an ideal opportunity to study the polynya’s impact on the overlying and surrounding atmosphere. This has been pursued here by investigating the seasonal cycle of differences of surface and air-column variables between polynya and non-polynya years. Ourmore » results indicate significant local impacts on turbulent heat fluxes, precipitation, cloud characteristics, and radiative fluxes. In particular, we find that clouds over polynyas are optically thicker and higher than clouds over sea ice during non-polynya years. Although the lower albedo of polynyas significantly increases the net shortwave absorption, the enhanced cloud brightness tempers this increase by almost 50%. Also, in this model, enhanced longwave radiation emitted from the warmer surface of polynyas is balanced by stronger downwelling fluxes from the thicker cloud deck. Impacts are found to be sensitive to the synoptic wind direction. Strongest regional impacts are found when northeasterly winds cross the polynya and interact with katabatic winds. Finally, surface air pressure anomalies over the polynya are only found to be significant when cold, dry air masses strike over the polynya, i.e. in case of southerly winds.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/1338761','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/1338761"><span>Local atmospheric response to an <span class="hlt">open-ocean</span> polynya in a high-resolution climate model</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Weijer, Wilbert; Veneziani, Milena; Stössel, Achim; Hecht, Matthew W.; Jeffery, Nicole; Jonko, Alexandra; Hodos, Travis; Wang, Hailong</p> <p>2016-11-17</p> <p>For this scientific paper, we study the atmospheric response to an <span class="hlt">open-ocean</span> polynya in the Southern <span class="hlt">Ocean</span> by analyzing the results from an atmospheric and <span class="hlt">oceanic</span> synoptic-scale resolving Community Earth System Model (CESM) simulation. While coarser-resolution versions of CESM generally do not produce <span class="hlt">open-ocean</span> polynyas in the Southern <span class="hlt">Ocean</span>, they do emerge and disappear on interannual timescales in the synoptic-scale simulation. This provides an ideal opportunity to study the polynya’s impact on the overlying and surrounding atmosphere. This has been pursued here by investigating the seasonal cycle of differences of surface and air-column variables between polynya and non-polynya years. Our results indicate significant local impacts on turbulent heat fluxes, precipitation, cloud characteristics, and radiative fluxes. In particular, we find that clouds over polynyas are optically thicker and higher than clouds over sea ice during non-polynya years. Although the lower albedo of polynyas significantly increases the net shortwave absorption, the enhanced cloud brightness tempers this increase by almost 50%. Also, in this model, enhanced longwave radiation emitted from the warmer surface of polynyas is balanced by stronger downwelling fluxes from the thicker cloud deck. Impacts are found to be sensitive to the synoptic wind direction. Strongest regional impacts are found when northeasterly winds cross the polynya and interact with katabatic winds. Finally, surface air pressure anomalies over the polynya are only found to be significant when cold, dry air masses strike over the polynya, i.e. in case of southerly winds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19810059141&hterms=water+quality&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dwater%2Bquality','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19810059141&hterms=water+quality&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dwater%2Bquality"><span>Use of <span class="hlt">ocean</span> color scanner data in <span class="hlt">water</span> quality mapping</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Khorram, S.</p> <p>1981-01-01</p> <p>Remotely sensed data, in combination with in situ data, are used in assessing <span class="hlt">water</span> quality parameters within the San Francisco Bay-Delta. The parameters include suspended solids, chlorophyll, and turbidity. Regression models are developed between each of the <span class="hlt">water</span> quality parameter measurements and the <span class="hlt">Ocean</span> Color Scanner (OCS) data. The models are then extended to the entire study area for mapping <span class="hlt">water</span> quality parameters. The results include a series of color-coded maps, each pertaining to one of the <span class="hlt">water</span> quality parameters, and the statistical analysis of the OCS data and regression models. It is found that concurrently collected OCS data and surface truth measurements are highly useful in mapping the selected <span class="hlt">water</span> quality parameters and locating areas having relatively high biological activity. In addition, it is found to be virtually impossible, at least within this test site, to locate such areas on U-2 color and color-infrared photography.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ESASP.740E..56H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ESASP.740E..56H"><span><span class="hlt">Ocean</span> Colour Remote Sensing of Extreme Case-2 <span class="hlt">Waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hieronymi, Martin; Krasemann, Hajo; Muller, Dagmar; Brockmann, Carsten; Ruescas, Ana; Stelzer, Kerstin; Nechad, Bouchra; Ruddick, Kevin; Simis, Stefan; Tilstone, Gavin; Steinmetz, Francois; Regner, Peter</p> <p>2016-08-01</p> <p>Many coastal seas and inland <span class="hlt">waters</span> have <span class="hlt">water</span> properties which are outside the normal conditions used for <span class="hlt">ocean</span> colour algorithm design. In the ESA-funded "Case-2 Extreme" project, retrieval methods for OC products in extreme Case-2 <span class="hlt">waters</span> are developed, tested, implemented, and validated primarily with reference to the capabilities of the Sentinel-3 OLCI and SLSTR instruments but also tested for Sentinel 2 where applicable. Based on hyperspectral radiative transfer simulation, in situ, and Earth observation data, specific features of extreme scattering and absorbing <span class="hlt">waters</span> are reviewed. A reflectance-based sub-classification scheme of Case-2 <span class="hlt">waters</span> for various levels of turbidity is introduced. Opportunities of using new wavebands are highlighted.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000083900&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000083900&hterms=sea+wave+power&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dsea%2Bwave%2Bpower"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span> and at Landfall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walsh, Edward J.; Wright, C. Wayne; Vandemark, Douglas C.; Krabill, William B.; Garcia, Andrew W.; Houston, Samuel H.; Powell, Mark D.; Black, Peter G.; Marks, Frank D.</p> <p>2000-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane hunter aircraft at 1.5 km height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. At 8 Hz, the SRA sweeps a radar beam of 1' half-power width (two-way) across the aircraft ground track over a swath equal to 0.8 of the aircraft height, simultaneously measuring the backscattered power at its 36 GHz (8.3 mm) operating frequency and the range to the sea surface at 64 positions. These slant ranges are multiplied by the cosine of the off-nadir angles to determine the vertical distances from the aircraft to the sea surface. Subtracting these distances from the aircraft height produces the sea surface elevation map. The sea surface topography is interpolated to a uniform grid, transformed by a two dimensional FFT, and Doppler corrected. The <span class="hlt">open-ocean</span> data were acquired on 24 August 1998 when hurricane Bonnie was east of the Bahamas and moving toward 330 deg at about 5 m/s. Individual waves up to 18 m height were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At some positions there were three different wave fields of comparable energy crossing each other. The NOAA aircraft spent over five hours within 180 km of the eye, and made five eye penetrations. On 26 August 1998, the NOAA aircraft flew at 2.2 km height when hurricane Bonnie was making landfall near Wilmington, NC, documenting the directional wave spectrum in the region between Charleston, SC and Cape Hatteras, NC. The aircraft flight lines included segments near and along the shoreline as well as far offshore. Animations of the directional wave spectrum spatial variation along the aircraft tracks on the two flights</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20000083900&hterms=Hurricane+Andrew&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BAndrew','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20000083900&hterms=Hurricane+Andrew&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DHurricane%2BAndrew"><span>Hurricane Directional Wave Spectrum Spatial Variation in the <span class="hlt">Open</span> <span class="hlt">Ocean</span> and at Landfall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Walsh, Edward J.; Wright, C. Wayne; Vandemark, Douglas C.; Krabill, William B.; Garcia, Andrew W.; Houston, Samuel H.; Powell, Mark D.; Black, Peter G.; Marks, Frank D.</p> <p>2000-01-01</p> <p>The sea surface directional wave spectrum was measured for the first time in all quadrants of a hurricane in <span class="hlt">open</span> <span class="hlt">water</span> using the NASA airborne scanning radar altimeter (SRA) carried aboard one of the NOAA WP-3D hurricane hunter aircraft at 1.5 km height. The SRA measures the energetic portion of the directional wave spectrum by generating a topographic map of the sea surface. At 8 Hz, the SRA sweeps a radar beam of 1' half-power width (two-way) across the aircraft ground track over a swath equal to 0.8 of the aircraft height, simultaneously measuring the backscattered power at its 36 GHz (8.3 mm) operating frequency and the range to the sea surface at 64 positions. These slant ranges are multiplied by the cosine of the off-nadir angles to determine the vertical distances from the aircraft to the sea surface. Subtracting these distances from the aircraft height produces the sea surface elevation map. The sea surface topography is interpolated to a uniform grid, transformed by a two dimensional FFT, and Doppler corrected. The <span class="hlt">open-ocean</span> data were acquired on 24 August 1998 when hurricane Bonnie was east of the Bahamas and moving toward 330 deg at about 5 m/s. Individual waves up to 18 m height were observed and the spatial variation of the wave field was dramatic. The dominant waves generally propagated at significant angles to the downwind direction. At some positions there were three different wave fields of comparable energy crossing each other. The NOAA aircraft spent over five hours within 180 km of the eye, and made five eye penetrations. On 26 August 1998, the NOAA aircraft flew at 2.2 km height when hurricane Bonnie was making landfall near Wilmington, NC, documenting the directional wave spectrum in the region between Charleston, SC and Cape Hatteras, NC. The aircraft flight lines included segments near and along the shoreline as well as far offshore. Animations of the directional wave spectrum spatial variation along the aircraft tracks on the two flights</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015ESDD....6.2137S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015ESDD....6.2137S"><span>Importance of <span class="hlt">open-water</span> ice growth and ice concentration evolution: a study based on FESOM-ECHAM6</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shi, X.; Lohmann, G.</p> <p>2015-10-01</p> <p>A newly developed global climate model FESOM-ECHAM6 with an unstructured mesh and high resolution is applied to investigate to what degree the area-thickness distribution of new ice formed in <span class="hlt">open</span> <span class="hlt">water</span> affects the ice and <span class="hlt">ocean</span> properties. A sensitivity experiment is performed which reduces the horizontal-to-vertical aspect ratio of <span class="hlt">open-water</span> ice growth. The resulting decrease in the Arctic winter sea-ice concentration strongly reduces the surface albedo, enhances the <span class="hlt">ocean</span> heat release to the atmosphere, and increases the sea-ice production. Furthermore, our simulations show a positive feedback mechanism among the Arctic sea ice, the Atlantic Meridional Overturning Circulation (AMOC), and the surface air temperature in the Arctic, as the sea ice transport affects the freshwater budget in regions of deep <span class="hlt">water</span> formation. A warming over Europe, Asia and North America, associated with a negative anomaly of Sea Level Pressure (SLP) over the Arctic (positive phase of the Arctic Oscillation (AO)), is also simulated by the model. For the Southern <span class="hlt">Ocean</span>, the most pronounced change is a warming along the Antarctic Circumpolar Current (ACC), especially for the Pacific sector. Additionally, a series of sensitivity tests are performed using an idealized 1-D thermodynamic model to further investigate the influence of the <span class="hlt">open-water</span> ice growth, which reveals similar results in terms of the change of sea ice and <span class="hlt">ocean</span> temperature. In reality, the distribution of new ice on <span class="hlt">open</span> <span class="hlt">water</span> relies on many uncertain parameters, for example, surface albedo, wind speed and <span class="hlt">ocean</span> currents. Knowledge of the detailed processes is currently too crude for those processes to be implemented realistically into models. Our sensitivity experiments indicate a pronounced uncertainty related to <span class="hlt">open-water</span> sea ice growth which could significantly affect the climate system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.G33E..07A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.G33E..07A"><span>SWOT, The Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography Satellite Mission (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Alsdorf, D.; Andreadis, K.; Bates, P. D.; Biancamaria, S.; Clark, E.; Durand, M. T.; Fu, L.; Lee, H.; Lettenmaier, D. P.; Mognard, N. M.; Moller, D.; Morrow, R. A.; Rodriguez, E.; Shum, C.</p> <p>2009-12-01</p> <p>Surface fresh <span class="hlt">water</span> is essential for life, yet we have surprisingly poor knowledge of its variability in space and time. Similarly, <span class="hlt">ocean</span> circulation fundamentally drives global climate variability, yet the <span class="hlt">ocean</span> current and eddy field that affects <span class="hlt">ocean</span> circulation and heat transport at the sub-mesoscale resolution and particularly near coastal and estuary regions, is poorly known. About 50% of the vertical exchange of <span class="hlt">water</span> properties (nutrients, dissovled CO2, heat, etc) in the upper <span class="hlt">ocean</span> is taking place at the sub-mesoscale. Measurements from the Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography satellite mission (SWOT) will make strides in understanding these processes and improving global <span class="hlt">ocean</span> models for studying climate change. SWOT is a swath-based interferometric-altimeter designed to acquire elevations of <span class="hlt">ocean</span> and terrestrial <span class="hlt">water</span> surfaces at unprecedented spatial and temporal resolutions. The mission will provide measurements of storage changes in lakes, reservoirs, and wetlands as well as estimates of discharge in rivers. These measurements are important for global <span class="hlt">water</span> and energy budgets, constraining hydrodynamic models of floods, carbon evasion through wetlands, and <span class="hlt">water</span> management, especially in developing nations. Perhaps most importantly, SWOT measurements will provide a fundamental understanding of the spatial and temporal variations in global surface <span class="hlt">waters</span>, which for many countries are the primary source of <span class="hlt">water</span>. An on-going effort, the “virtual mission” (VM) is designed to help constrain the required height and slope accuracies, the spatial sampling (both pixels and orbital coverage), and the trade-offs in various temporal revisits. Example results include the following: (1) Ensemble Kalman filtering of VM simulations recover <span class="hlt">water</span> depth and discharge, reducing the discharge RMSE from 23.2% to 10.0% over an 84-day simulation period, relative to a simulation without assimilation. (2) Ensemble-based data assimilation of SWOT like measurements yields</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.9145M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.9145M"><span>Mantle flow and <span class="hlt">oceanic</span> crust formation during the <span class="hlt">opening</span> of the Tyrrhenian back-arc basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Magni, Valentina</p> <p>2017-04-01</p> <p>The formation of the Tyrrhenian back-arc basin occurred through short-lived episodes of fast spreading alternated with periods of slow rifting. I present results from three-dimensional numerical models of laterally varying subduction to explain the mechanism of back-arc basin <span class="hlt">opening</span> and its episodic spreading behaviour. Moreover, I explore the consequences of this alternation between fast and slow episodes of extension on the production of new <span class="hlt">oceanic</span> crust in the back-arc basin. Results show that the presence of continental plates (i.e. Africa and Adria) nearby the <span class="hlt">oceanic</span> subduction of the Ionian slab produces localised deformation within the overriding plate and it is, thus, crucial for the <span class="hlt">opening</span> of the back-arc basin. Moreover, the occurrence of collision results in the formation of two slab windows at the <span class="hlt">ocean</span>-continent boundaries, which is in very good agreement with what is observed in the Central Mediterranean, nearby the Calabrian slab. During the evolution of the system the trench velocity shows pulses of fast trench retreat that last a few millions of years. This is associated with episodes of more intense melting of the asthenosphere rising at the back-arc basin. Finally, these three-dimensional models are used to track the mantle flow throughout the model evolution and the source of the mantle melting at the spreading centre.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5353760','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5353760"><span>Bromoform production in tropical <span class="hlt">open-ocean</span> <span class="hlt">waters</span>: OTEC chlorination</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hartwig, E.O.; Valentine, R.</p> <p>1981-09-01</p> <p>The bromoform, and other volatile organics produced while chlorinating both the evaporator and condenser seawater during operation of the one megawatt (1 MW) OTEC-1 test facility are reported. Although many halogenated compounds might be produced as a result of chlorination, the quantitative analyses in this study focused on volatile EPA priority pollutants. Bromoform is the compound specifically recognized as a potential pollutant. Its concentration may be indicative of other halogenated species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.5067M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.5067M"><span>Satellite altimetry in sea ice regions - detecting <span class="hlt">open</span> <span class="hlt">water</span> for estimating sea surface heights</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Müller, Felix L.; Dettmering, Denise; Bosch, Wolfgang</p> <p>2017-04-01</p> <p>The Greenland Sea and the Farm Strait are transporting sea ice from the central Arctic <span class="hlt">ocean</span> southwards. They are covered by a dynamic changing sea ice layer with significant influences on the Earth climate system. Between the sea ice there exist various sized <span class="hlt">open</span> <span class="hlt">water</span> areas known as leads, straight lined <span class="hlt">open</span> <span class="hlt">water</span> areas, and polynyas exhibiting a circular shape. Identifying these leads by satellite altimetry enables the extraction of sea surface height information. Analyzing the radar echoes, also called waveforms, provides information on the surface backscatter characteristics. For example waveforms reflected by calm <span class="hlt">water</span> have a very narrow and single-peaked shape. Waveforms reflected by sea ice show more variability due to diffuse scattering. Here we analyze altimeter waveforms from different conventional pulse-limited satellite altimeters to separate <span class="hlt">open</span> <span class="hlt">water</span> and sea ice waveforms. An unsupervised classification approach employing partitional clustering algorithms such as K-medoids and memory-based classification methods such as K-nearest neighbor is used. The classification is based on six parameters derived from the waveform's shape, for example the maximum power or the peak's width. The <span class="hlt">open-water</span> detection is quantitatively compared to SAR images processed while accounting for sea ice motion. The classification results are used to derive information about the temporal evolution of sea ice extent and sea surface heights. They allow to provide evidence on climate change relevant influences as for example Arctic sea level rise due to enhanced melting rates of Greenland's glaciers and an increasing fresh <span class="hlt">water</span> influx into the Arctic <span class="hlt">ocean</span>. Additionally, the sea ice cover extent analyzed over a long-time period provides an important indicator for a globally changing climate system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5673156','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5673156"><span>Distribution of copper, nickel, and cadmium in the surface <span class="hlt">waters</span> of the North Atlantic and North Pacific <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Boyle, E.A.; Huested, S.S.; Jones, S.P.</p> <p>1981-09-20</p> <p>Concentrations of copper, nickel, and cadmium have been determined for about 250 surface <span class="hlt">water</span> samples. Nonupwelling <span class="hlt">open-ocean</span> concentrations of these metals are Cu, 0.5-1.4 nmol/kg: Ni, 1-2 nmol/kg; and Cd, less than 10 pmol/kg. In the equatorial Pacific upwelling zone, concentrations of Ni (3 nmol/kg) and Cd (80 pmol/kg) are higher than in the <span class="hlt">open</span> <span class="hlt">ocean</span>, but Cu (0.9 nmol/kg) is not significantly enriched. Metal concentrations are higher in cool, nutrient-rich eastern boundary currents: Cu, 1.5 nmol/kg: Ni, 3.5 nmol/kg and Cd, 30-50 pmol/kg. Copper is distinctly higher in the coastal <span class="hlt">waters</span> of the Gulf of Panama (3--4 nmol/kg) and also higher in the shelf <span class="hlt">waters</span> north of the Gulf Stream (2.5 nmol/kg): these copper enrichments may be caused by copper remobilized from mildly reducing shelf sediments and maintained by a coastal nutrient trap. In the <span class="hlt">open</span> <span class="hlt">ocean</span>, events of high-Cu <span class="hlt">water</span> (1.5--3.5 nmol/kg) are seen on scales up to 60 km; presumably, these are due to the advection of coastal <span class="hlt">water</span> into the <span class="hlt">ocean</span> interior. The lowest copper concentrations in the North Pacific central gyre (0.5 nmol/kg: (Bruland, 1980) are lower than in the Sargasso Sea (1.3 nmol/kg), while for nickel the lowest concentrations are 2 nmol/kg in both the North Pacific and the North Atlantic. Nickel and cadmium, while generally correlated with the nutrients in surface <span class="hlt">waters</span>, show distinct regional changes in their element-nutrient correlations. The residual concentrations of trace metals in the surface <span class="hlt">waters</span> of the <span class="hlt">ocean</span> can be explained if biological discrimination against trace metals relative to phosphorus increases as productivity decreases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.C21C0705K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.C21C0705K"><span>Preconditioning and Formation Mechanisms of Maud Rise (<span class="hlt">Open</span> <span class="hlt">Ocean</span>) Polynyas in a High-Resolution CESM Simulation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kurtakoti, P. K.; Veneziani, C.; Stoessel, A.; Weijer, W.</p> <p>2016-12-01</p> <p>Processes responsible for preconditioning and formation of Maud Rise Polynyas (MRP) were analyzed within the framework of a high-resolution fully coupled Community Earth System Model (CESM) simulation. <span class="hlt">Open</span> <span class="hlt">Ocean</span> Polynyas (OOPs) are large ice-free areas within the winter ice pack. These are regions of deep convection and strong atmosphere-ice-<span class="hlt">ocean</span> interaction through which they play an important role in the formation of bottom <span class="hlt">waters</span>. The data analyzed comes from a simulation conducted in a pre-industrial scenario as part of the Accelerated Climate Modeling for Energy (ACME) project. Within this simulation, persistent winter OOPs were simulated in the Weddell Sea (Weddell Sea Polynya) and over the Maud Rise seamount (Maud Rise Polynya). The sea ice concentration in the Weddell Sea shows that MRP acts as a precondition to Weddell Sea polynyas, which is consistent with mid 1970s observations of a westward expansion of MRP into the Weddell Sea. The OOPs in years 30-40 of the CESM simulation are largely over Maud Rise giving us an opportunity to investigate processes that trigger and maintain the OOP in winter over Maud Rise. The heat content of the Weddell Deep <span class="hlt">Water</span> (WDW) is seen to be an important factor for MRPs, consistent with previous studies. The first MRP in the 30s coincides with the strongest negative wind stress curl over the Weddell Sea, which implies that this condition is a triggering mechanism for deep convection. The deep convective event associated with the OOP leads to a reduction of deep <span class="hlt">ocean</span> heat reservoir up to 3000m depth. The simulation captures a westward flow of WDW impinging on Maud Rise seamount. Previous studies suggest Taylor column dynamics to be necessary for MRPs to emerge. We have explored how Taylor column dynamics could contribute to preconditioning and triggering deep <span class="hlt">open</span> <span class="hlt">ocean</span> convection over Maud Rise Seamount. We also investigate the importance of resolution of bottom topography for the formation of a strong enough Taylor</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015GBioC..29..917C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015GBioC..29..917C"><span><span class="hlt">Water</span> mass age and aging driving chromophoric dissolved organic matter in the dark global <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Catalá, T. S.; Reche, I.; Álvarez, M.; Khatiwala, S.; Guallart, E. F.; Benítez-Barrios, V. M.; Fuentes-Lema, A.; Romera-Castillo, C.; Nieto-Cid, M.; Pelejero, C.; Fraile-Nuez, E.; Ortega-Retuerta, E.; Marrasé, C.; Álvarez-Salgado, X. A.</p> <p>2015-07-01</p> <p>The omnipresence of chromophoric dissolved organic matter (CDOM) in the <span class="hlt">open</span> <span class="hlt">ocean</span> enables its use as a tracer for biochemical processes throughout the global overturning circulation. We made an inventory of CDOM optical properties, ideal <span class="hlt">water</span> age (τ), and apparent oxygen utilization (AOU) along the Atlantic, Indian, and Pacific <span class="hlt">Ocean</span> <span class="hlt">waters</span> sampled during the Malaspina 2010 expedition. A <span class="hlt">water</span> mass analysis was applied to obtain intrinsic, hereinafter archetypal, values of τ, AOU, oxygen utilization rate (OUR), and CDOM absorption coefficients, spectral slopes and quantum yield for each one of the 22 <span class="hlt">water</span> types intercepted during this circumnavigation. Archetypal values of AOU and OUR have been used to trace the differential influence of <span class="hlt">water</span> mass aging and aging rates, respectively, on CDOM variables. Whereas the absorption coefficient at 325 nm (a325) and the fluorescence quantum yield at 340 nm (Φ340) increased, the spectral slope over the wavelength range 275-295 nm (S275-295) and the ratio of spectral slopes over the ranges 275-295 nm and 350-400 nm (SR) decreased significantly with <span class="hlt">water</span> mass aging (AOU). Combination of the slope of the linear regression between archetypal AOU and a325 with the estimated global OUR allowed us to obtain a CDOM turnover time of 634 ± 120 years, which exceeds the flushing time of the dark <span class="hlt">ocean</span> (>200 m) by 46%. This positive relationship supports the assumption of in situ production and accumulation of CDOM as a by-product of microbial metabolism as <span class="hlt">water</span> masses turn older. Furthermore, our data evidence that global-scale CDOM quantity (a325) is more dependent on aging (AOU), whereas CDOM quality (S275-295, SR, Φ340) is more dependent on aging rate (OUR).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010389','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010389"><span>Spatially Resolving <span class="hlt">Ocean</span> Color and Sediment Dispersion in River Plumes, Coastal Systems, and Continental Shelf <span class="hlt">Waters</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Aurin, Dirk Alexander; Mannino, Antonio; Franz, Bryan</p> <p>2013-01-01</p> <p>Satellite remote sensing of <span class="hlt">ocean</span> color in dynamic coastal, inland, and nearshorewaters is impeded by high variability in optical constituents, demands specialized atmospheric correction, and is limited by instrument sensitivity. To accurately detect dispersion of bio-optical properties, remote sensors require ample signal-to-noise ratio (SNR) to sense small variations in <span class="hlt">ocean</span> color without saturating over bright pixels, an atmospheric correction that can accommodate significantwater-leaving radiance in the near infrared (NIR), and spatial and temporal resolution that coincides with the scales of variability in the environment. Several current and historic space-borne sensors have met these requirements with success in the <span class="hlt">open</span> <span class="hlt">ocean</span>, but are not optimized for highly red-reflective and heterogeneous <span class="hlt">waters</span> such as those found near river outflows or in the presence of sediment resuspension. Here we apply analytical approaches for determining optimal spatial resolution, dominant spatial scales of variability ("patches"), and proportions of patch variability that can be resolved from four river plumes around the world between 2008 and 2011. An offshore region in the Sargasso Sea is analyzed for comparison. A method is presented for processing Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua and Terra imagery including cloud detection, stray lightmasking, faulty detector avoidance, and dynamic aerosol correction using short-wave- and near-infrared wavebands in extremely turbid regions which pose distinct optical and technical challenges. Results showthat a pixel size of approx. 520 mor smaller is generally required to resolve spatial heterogeneity in <span class="hlt">ocean</span> color and total suspended materials in river plumes. Optimal pixel size increases with distance from shore to approx. 630 m in nearshore regions, approx 750 m on the continental shelf, and approx. 1350 m in the <span class="hlt">open</span> <span class="hlt">ocean</span>. Greater than 90% of the optical variability within plume regions is resolvable with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=19920019347&hterms=pac&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dpac','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=19920019347&hterms=pac&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dpac"><span>A magma <span class="hlt">ocean</span> and the Earth's internal <span class="hlt">water</span> budget</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ahrens, Thomas J.</p> <p>1992-01-01</p> <p>There are lines of evidence which relate bounds on the primordial <span class="hlt">water</span> content of the Earth's mantle to a magma <span class="hlt">ocean</span> and the accompanying Earth accretion process. We assume initially (before a magma <span class="hlt">ocean</span> could form) that as the Earth accreted, it grew from volatile- (H2O, CO2, NH3, CH4, SO2, plus noble) gas-rich planetesimals, which accreted to form an initial 'primitive accretion core' (PAC). The PAC retained the initial complement of planetesimal gaseous components. Shock wave experiments in which both solid, and more recently, the gaseous components of materials such as serpentine and the Murchison meteorite have demonstrated that planetesimal infall velocities of less than 0.5 km/sec, induce shock pressures of less than 0.5 GPa and result in virtually complete retention of planetary gases.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840019234','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840019234"><span>Modeling of SAR signatures of shallow <span class="hlt">water</span> <span class="hlt">ocean</span> topography</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shuchman, R. A.; Kozma, A.; Kasischke, E. S.; Lyzenga, D. R.</p> <p>1984-01-01</p> <p>A hydrodynamic/electromagnetic model was developed to explain and quantify the relationship between the SEASAT synthetic aperture radar (SAR) observed signatures and the bottom topography of the <span class="hlt">ocean</span> in the English Channel region of the North Sea. The model uses environmental data and radar system parameters as inputs and predicts SAR-observed backscatter changes over topographic changes in the <span class="hlt">ocean</span> floor. The model results compare favorably with the actual SEASAT SAR observed backscatter values. The developed model is valid for only relatively shallow <span class="hlt">water</span> areas (i.e., less than 50 meters in depth) and suggests that for bottom features to be visible on SAR imagery, a moderate to high velocity current and a moderate wind must be present.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20070034849&hterms=evaporation+water+oceans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Devaporation%2Bwater%2Boceans','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20070034849&hterms=evaporation+water+oceans&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Devaporation%2Bwater%2Boceans"><span>Moisture Advection and Fresh <span class="hlt">Water</span> Flux over <span class="hlt">Oceans</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tang, Wenqing; Liu, W. Timothy</p> <p>2002-01-01</p> <p>Moisture transport in the atmosphere is one of the most significant components in the hydrological cycle. Under stationary condition, <span class="hlt">ocean</span> surface fresh <span class="hlt">water</span> flux, which is the difference between precipitation (P) and evaporation (E), is balanced by the divergence of column-integrated moisture transport (IMT) in the atmosphere. Characterizing accurately a global picture of IMT from observation is a difficult task. It requires measurements of vertical profiles for wind vector and humidity. More specifically, IMT can be defined as the integration in pressure coordinates the product of specific humidity q and wind vector u, where g is the gravitational acceleration, and p, is the atmospheric pressure at <span class="hlt">ocean</span> surface.In this study, a statistical relationship is derived between u, and u(sub)s using data from numerical weather prediction model. The relationship is then validated using surface and vertical profile from radiosonde data, before applied to spacebased measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015418','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015418"><span>Evaluation and Windspeed Dependence of MODIS Aerosol Retrievals Over <span class="hlt">Open</span> <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kleidman, Richard G.; Smirnov, Alexander; Levy, Robert C.; Mattoo, Shana; Tanre, Didier</p> <p>2011-01-01</p> <p>The Maritime Aerosol Network (MAN) data set provides high quality ground-truth to validate the MODIS aerosol product over <span class="hlt">open</span> <span class="hlt">ocean</span>. Prior validation of the <span class="hlt">ocean</span> aerosol product has been limited to coastal and island sites. Comparing MODIS Collection 5 <span class="hlt">ocean</span> aerosol retrieval products with collocated MAN measurements from ships shows that MODIS is meeting the pre-launch uncertainty estimates for aerosol optical depth (AOD) with 64% and 67% of retrievals at 550 nm, and 74% and 78% of retrievals at 870 nm, falling within expected uncertainty for Terra and Aqua, respectively. Angstrom Exponent comparisons show a high correlation between MODIS retrievals and shipboard measurements (R= 0.85 Terra, 0.83 Aqua), although the MODIS aerosol algorithm tends to underestimate particle size for large particles and overestimate size for small particles, as seen in earlier Collections. Prior analysis noted an offset between Terra and Aqua <span class="hlt">ocean</span> AOD, without concluding which sensor was more accurate. The simple linear regression reported here, is consistent with other anecdotal evidence that Aqua agreement with AERONET is marginally better. However we cannot claim based on the current study that the better Aqua comparison is statistically significant. Systematic increase of error as a function of wind speed is noted in both Terra and Aqua retrievals. This wind speed dependency enters the retrieval when winds deviate from the 6 m/s value assumed in the rough <span class="hlt">ocean</span> surface and white cap parameterizations. Wind speed dependency in the results can be mitigated by using auxiliary NCEP wind speed information in the retrieval process.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002cosp...34E.837R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002cosp...34E.837R"><span>SeaWiFS data from <span class="hlt">oceanic</span> <span class="hlt">waters</span> around New Zealand: Validation and applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Richardson, K.; Boyd, P.; Gall, M.; Pinkerton, M.</p> <p></p> <p>Satellite observations of <span class="hlt">ocean</span> colour are the only realistic way to measure phytoplankton abundance at regional and global scales. NASA's Sea-viewing Wide Field -o f-view Sensor (SeaWiFS) began operation in September 1997 and is still providing data today. The data are of particular value to New Zealand, which has the fourth largest Exclusive Economic Zone (EEZ) in the world (some 4 million km2 ). Analysis of moderate resolution (9 km) SeaWiFS monthly Standard Mapped Images has substantially increased knowledge of the dynamics of chlorophyll concentrations around New Zealand. SeaWiFS data over nearly three years shows that northern New Zealand Subtropical and Tasman Sea <span class="hlt">waters</span> follow a classical cycle of spring and autumn chlorophyll blooms consistent with production being co-limited by nitrate and light. Subantarctic <span class="hlt">Waters</span> south of New Zealand had a low-magnitude annual cycle of chlorophyll abundance that peaked in early autumn, consistent with production being principally iron-limited. Chlorophyll was generally highest in the Subtropical Front either side of New Zealand where Subtropical and Subantarctic <span class="hlt">waters</span> mix. NIWA (National Institute of <span class="hlt">Water</span> and Atmospheric Research) has been receiving and processing high resolution (1.1 km) SeaWiFS data for the NZ region since May 2000. In addition to this, extensive bio-optical data from a number of NIWA cruises are being used to validate the satellite data and assess the accuracy of the <span class="hlt">ocean</span> products in New Zealand <span class="hlt">open</span> <span class="hlt">ocean</span> and coastal <span class="hlt">waters</span>. The performance of the SeaWiFS chlorophyll-a algorithm (OC4v4) has been investigated by comparing high-precision in situ measurements of the underwater radiation field with measurements of phytoplankton pigment concentration. Analyses of these results suggest that the algorithm may be performing well in the <span class="hlt">open</span> <span class="hlt">ocean</span> for chlorophyll- a concentrations below 0.3-0.4 mg m-3 but overestimating by a factor of two or more at higher concentrations. NIWA believes that <span class="hlt">ocean</span> colour</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3707865','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3707865"><span>Deep-Sea Bioluminescence Blooms after Dense <span class="hlt">Water</span> Formation at the <span class="hlt">Ocean</span> Surface</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L.; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C.; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q.; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J.; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Motz, Holger; Neff, Max; Nezri, Emma nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E.; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G.; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J. M.; Stolarczyk, Thierry; Taiuti, Mauro G. F.; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan</p> <p>2013-01-01</p> <p>The deep <span class="hlt">ocean</span> is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep <span class="hlt">waters</span>. Such changes are triggered by the winter cooling and evaporation experienced by the upper <span class="hlt">ocean</span> layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense <span class="hlt">water</span> through a process known as “<span class="hlt">open</span>-sea convection”. It episodically renews the deep <span class="hlt">water</span> of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep <span class="hlt">open</span>-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense <span class="hlt">water</span> formation events are likely to decline under global warming scenarios enhancing <span class="hlt">ocean</span> stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts. PMID:23874425</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23874425','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23874425"><span>Deep-sea bioluminescence blooms after dense <span class="hlt">water</span> formation at the <span class="hlt">ocean</span> surface.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tamburini, Christian; Canals, Miquel; Durrieu de Madron, Xavier; Houpert, Loïc; Lefèvre, Dominique; Martini, Séverine; D'Ortenzio, Fabrizio; Robert, Anne; Testor, Pierre; Aguilar, Juan Antonio; Samarai, Imen Al; Albert, Arnaud; André, Michel; Anghinolfi, Marco; Anton, Gisela; Anvar, Shebli; Ardid, Miguel; Jesus, Ana Carolina Assis; Astraatmadja, Tri L; Aubert, Jean-Jacques; Baret, Bruny; Basa, Stéphane; Bertin, Vincent; Biagi, Simone; Bigi, Armando; Bigongiari, Ciro; Bogazzi, Claudio; Bou-Cabo, Manuel; Bouhou, Boutayeb; Bouwhuis, Mieke C; Brunner, Jurgen; Busto, José; Camarena, Francisco; Capone, Antonio; Cârloganu, Christina; Carminati, Giada; Carr, John; Cecchini, Stefano; Charif, Ziad; Charvis, Philippe; Chiarusi, Tommaso; Circella, Marco; Coniglione, Rosa; Costantini, Heide; Coyle, Paschal; Curtil, Christian; Decowski, Patrick; Dekeyser, Ivan; Deschamps, Anne; Donzaud, Corinne; Dornic, Damien; Dorosti, Hasankiadeh Q; Drouhin, Doriane; Eberl, Thomas; Emanuele, Umberto; Ernenwein, Jean-Pierre; Escoffier, Stéphanie; Fermani, Paolo; Ferri, Marcelino; Flaminio, Vincenzo; Folger, Florian; Fritsch, Ulf; Fuda, Jean-Luc; Galatà, Salvatore; Gay, Pascal; Giacomelli, Giorgio; Giordano, Valentina; Gómez-González, Juan-Pablo; Graf, Kay; Guillard, Goulven; Halladjian, Garadeb; Hallewell, Gregory; van Haren, Hans; Hartman, Joris; Heijboer, Aart J; Hello, Yann; Hernández-Rey, Juan Jose; Herold, Bjoern; Hößl, Jurgen; Hsu, Ching-Cheng; de Jong, Marteen; Kadler, Matthias; Kalekin, Oleg; Kappes, Alexander; Katz, Uli; Kavatsyuk, Oksana; Kooijman, Paul; Kopper, Claudio; Kouchner, Antoine; Kreykenbohm, Ingo; Kulikovskiy, Vladimir; Lahmann, Robert; Lamare, Patrick; Larosa, Giuseppina; Lattuada, Dario; Lim, Gordon; Presti, Domenico Lo; Loehner, Herbert; Loucatos, Sotiris; Mangano, Salvatore; Marcelin, Michel; Margiotta, Annarita; Martinez-Mora, Juan Antonio; Meli, Athina; Montaruli, Teresa; Moscoso, Luciano; Motz, Holger; Neff, Max; Nezri, Emma Nuel; Palioselitis, Dimitris; Păvălaş, Gabriela E; Payet, Kevin; Payre, Patrice; Petrovic, Jelena; Piattelli, Paolo; Picot-Clemente, Nicolas; Popa, Vlad; Pradier, Thierry; Presani, Eleonora; Racca, Chantal; Reed, Corey; Riccobene, Giorgio; Richardt, Carsten; Richter, Roland; Rivière, Colas; Roensch, Kathrin; Rostovtsev, Andrei; Ruiz-Rivas, Joaquin; Rujoiu, Marius; Russo, Valerio G; Salesa, Francisco; Sánchez-Losa, Augustin; Sapienza, Piera; Schöck, Friederike; Schuller, Jean-Pierre; Schussler, Fabian; Shanidze, Rezo; Simeone, Francesco; Spies, Andreas; Spurio, Maurizio; Steijger, Jos J M; Stolarczyk, Thierry; Taiuti, Mauro G F; Toscano, Simona; Vallage, Bertrand; Van Elewyck, Véronique; Vannoni, Giulia; Vecchi, Manuela; Vernin, Pascal; Wijnker, Guus; Wilms, Jorn; de Wolf, Els; Yepes, Harold; Zaborov, Dmitry; De Dios Zornoza, Juan; Zúñiga, Juan</p> <p>2013-01-01</p> <p>The deep <span class="hlt">ocean</span> is the largest and least known ecosystem on Earth. It hosts numerous pelagic organisms, most of which are able to emit light. Here we present a unique data set consisting of a 2.5-year long record of light emission by deep-sea pelagic organisms, measured from December 2007 to June 2010 at the ANTARES underwater neutrino telescope in the deep NW Mediterranean Sea, jointly with synchronous hydrological records. This is the longest continuous time-series of deep-sea bioluminescence ever recorded. Our record reveals several weeks long, seasonal bioluminescence blooms with light intensity up to two orders of magnitude higher than background values, which correlate to changes in the properties of deep <span class="hlt">waters</span>. Such changes are triggered by the winter cooling and evaporation experienced by the upper <span class="hlt">ocean</span> layer in the Gulf of Lion that leads to the formation and subsequent sinking of dense <span class="hlt">water</span> through a process known as "<span class="hlt">open</span>-sea convection". It episodically renews the deep <span class="hlt">water</span> of the study area and conveys fresh organic matter that fuels the deep ecosystems. Luminous bacteria most likely are the main contributors to the observed deep-sea bioluminescence blooms. Our observations demonstrate a consistent and rapid connection between deep <span class="hlt">open</span>-sea convection and bathypelagic biological activity, as expressed by bioluminescence. In a setting where dense <span class="hlt">water</span> formation events are likely to decline under global warming scenarios enhancing <span class="hlt">ocean</span> stratification, in situ observatories become essential as environmental sentinels for the monitoring and understanding of deep-sea ecosystem shifts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA623471','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA623471"><span>Do <span class="hlt">Open</span> Source Tools Rival Heritage Systems? A Comparison of Tide Models in <span class="hlt">OCEAN</span> and Orekit</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2014-08-01</p> <p>Do <span class="hlt">Open</span> Source Tools Rival Heritage Systems? A comparison of tide models in <span class="hlt">OCEAN</span> and Orekit Evan M. Ward∗ and John G. Warner∗ U.S. Naval Research...CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Maisonobe /Evan M. Ward John G. Warner Luc 5d. PROJECT NUMBER 5e...2012. 4Vetter, J. R., “Fifty Years of Orbit Determination: Development of Modern Astrydynamics Methods,” Johns Hopkins APL technical digest , Vol. 27, No</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011DSRII..58..734H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011DSRII..58..734H"><span>Defining dynamic pelagic habitats in <span class="hlt">oceanic</span> <span class="hlt">waters</span> off eastern Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hobday, A. J.; Young, J. W.; Moeseneder, C.; Dambacher, J. M.</p> <p>2011-03-01</p> <p>Although many species in the pelagic <span class="hlt">ocean</span> are widespread, they are not randomly distributed. These species may have associations with particular <span class="hlt">water</span> masses or habitats, but to best understand patterns in the <span class="hlt">ocean</span>, these habitats must be identified. Previous efforts have produced static or seasonal climatologies, which still represent smearing over habitats. The Eastern Tuna and Billfish Longline Fishery (ETBF) targets a range of high trophic level species in <span class="hlt">oceanic</span> <span class="hlt">waters</span> off eastern Australia. In this study, dynamic <span class="hlt">ocean</span> habitats in the region were identified for each month based on cluster analysis of five oceanographic variables averaged at a monthly time scale and a spatial scale of 0.5° for the period 1995-2006. A total of seven persistent habitats were identified off eastern Australia with intra and interannual variation in size and location, indicating the importance of spatial and temporal variation in the dynamics of the region. The degree to which these dynamic habitats were distinguished was tested using (i) stable isotope analysis of top fish predators caught in the region and (ii) estimates of variation in estimated abundance generated from catch data from the fishery. More precise estimates (measured as lower total CV) of isotopic values from swordfish ( Xiphias gladius), yellowfin tuna ( Thunnus albacares) and albacore ( Thunnus alalunga) were obtained for 4 of 6 isotope comparisons using the dynamic habitat groupings, which indicate that stratifying by pelagic habitat improved precision. Dynamic habitats produced more precise abundance estimates for 7 of 8 large pelagic species examined, with an average reduction in total CV of 19% compared to when abundance was estimated based on static habitat stratification. These findings could be used to guide development of effective monitoring strategies that can distinguish patterns due to environmental variation, and in the longer term, climate change.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=337050','PESTICIDES'); return false;" href="https://cfpub.epa.gov/si/si_public_record_report.cfm?direntryid=337050"><span>Assessment of the urban <span class="hlt">water</span> system with an <span class="hlt">open</span> ...</span></a></p> <p><a target="_blank" href="http://www.epa.gov/pesticides/search.htm">EPA Pesticide Factsheets</a></p> <p></p> <p></p> <p>Urban <span class="hlt">water</span> systems convey complex environmental and man-made flows. The relationships among <span class="hlt">water</span> flows and networked storages remains difficult to comprehensively evaluate. Such evaluation is important, however, as interventions are designed (e.g, conservation measures, green infrastructure) to modify specific flows of urban <span class="hlt">water</span> (e.g. drinking <span class="hlt">water</span>, stormwater) that may have systemic effects. We have developed a general model that specifies the relationships among urban <span class="hlt">water</span> system components, and a set of tools for evaluating the model for any city as the R package City<span class="hlt">Water</span>Balance. City<span class="hlt">Water</span>Balance provides a reproducible workflow for assessing urban <span class="hlt">water</span> system(s) by facilitating the retrieval of <span class="hlt">open</span> data, largely via web services, and analysis of these data using <span class="hlt">open</span>-source R functions. It allows the user to 1) quickly assemble a quantitative, unified picture of flows thorough an urban area, and 2) easily change the spatial and temporal boundaries of analysis to match scales relevant to local decision-making. We used City<span class="hlt">Water</span>Balance to evaluate the <span class="hlt">water</span> system in the Chicago metropolitan area on a monthly basis for <span class="hlt">water</span> years 2001-2010. Results, including the relative magnitudes and temporal variability of major <span class="hlt">water</span> flows in greater Chicago, are used to consider 1) trade-offs associated with management alternatives for stormwater and combined sewer overflows and 2) the significance of future changes in precipitation, which is the largest</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24554022','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24554022"><span>Monitoring of <span class="hlt">ocean</span> surface algal blooms in coastal and <span class="hlt">oceanic</span> <span class="hlt">waters</span> around India.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tholkapiyan, Muniyandi; Shanmugam, Palanisamy; Suresh, T</p> <p>2014-07-01</p> <p>The National Aeronautics and Space Administration's (NASA) sensor MODIS-Aqua provides an important tool for reliable observations of the changing <span class="hlt">ocean</span> surface algal bloom paradigms in coastal and <span class="hlt">oceanic</span> <span class="hlt">waters</span> around India. A time series of the MODIS-Aqua-derived OSABI (<span class="hlt">ocean</span> surface algal bloom index) and its seasonal composite images report new information and comprehensive pictures of these blooms and their evolution stages in a wide variety of events occurred at different times of the years from 2003 to 2011, providing the first large area survey of such phenomena around India. For most of the years, the results show a strong seasonal pattern of surface algal blooms elucidated by certain physical and meteorological conditions. The extent of these blooms reaches a maximum in winter (November-February) and a minimum in summer (June-September), especially in the northern Arabian Sea. Their spatial distribution and retention period are also significantly increased in the recent years. The increased spatial distribution and intensity of these blooms in the northern Arabian Sea in winter are likely caused by enhanced cooling, increased convective mixing, favorable winds, and atmospheric deposition of the mineral aerosols (from surrounding deserts) of the post-southwest monsoon period. The southward Oman coastal current and southwestward winds become apparently responsible for their extension up to the central Arabian Sea. Strong upwelling along this coast further triggers their initiation and growth. Though there is a warming condition associated with increased sea surface height anomalies along the coasts of India and Sri Lanka in winter, surface algal bloom patches are still persistent along these coasts due to northeast monsoonal winds, enhanced precipitation, and subsequent nutrient enrichment in these areas. The occurrence of the surface algal blooms in the northern Bay of Bengal coincides with a region of the well-known Ganges-Brahmaputra Estuarine Frontal</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.9653I','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.9653I"><span>Coastal <span class="hlt">water</span> quality estimation from Geostationary <span class="hlt">Ocean</span> Color Imager (GOCI) satellite data using machine learning approaches</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Im, Jungho; Ha, Sunghyun; Kim, Yong Hoon; Ha, Hokyung; Choi, Jongkuk; Kim, Miae</p> <p>2014-05-01</p> <p>It is important to monitor coastal <span class="hlt">water</span> quality using key parameters such as chlorophyll-a concentration and suspended sediment to better manage coastal areas as well as to better understand the nature of biophysical processes in coastal seawater. Remote sensing technology has been commonly used to monitor coastal <span class="hlt">water</span> quality due to its ability of covering vast areas at high temporal resolution. While it is relatively straightforward to estimate <span class="hlt">water</span> quality in <span class="hlt">open</span> <span class="hlt">ocean</span> (i.e., Case I <span class="hlt">water</span>) using remote sensing, coastal <span class="hlt">water</span> quality estimation is still challenging as many factors can influence <span class="hlt">water</span> quality, including various materials coming from inland <span class="hlt">water</span> systems and tidal circulation. There are continued efforts to accurately estimate <span class="hlt">water</span> quality parameters in coastal seawater from remote sensing data in a timely manner. In this study, two major <span class="hlt">water</span> quality indicators, chlorophyll-a concentration and the amount of suspended sediment, were estimated using Geostationary <span class="hlt">Ocean</span> Color Imager (GOCI) satellite data. GOCI, launched in June 2010, is the first geostationary <span class="hlt">ocean</span> color observation satellite in the world. GOCI collects data hourly for 8 hours a day at 6 visible and 2 near-infrared bands at a 500 m resolution with 2,500 x 2,500 km square around Korean peninsula. Along with conventional statistical methods (i.e., various linear and non-linear regression), three machine learning approaches such as random forest, Cubist, and support vector regression were evaluated for coastal <span class="hlt">water</span> quality estimation. In situ measurements (63 samples; including location, two <span class="hlt">water</span> quality parameters, and the spectra of surface <span class="hlt">water</span> using a hand-held spectroradiometer) collected during four days between 2011 and 2012 were used as reference data. Due to the small sample size, leave-one-out cross validation was used to assess the performance of the <span class="hlt">water</span> quality estimation models. Atmospherically corrected radiance data and selected band-ratioed images were used</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004IJTPE.124.1021A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004IJTPE.124.1021A"><span><span class="hlt">Open</span> Cycle OTEC System with Fresh <span class="hlt">Water</span> Product</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Amano, Masatugu; Tanaka, Tadayosi</p> <p></p> <p>An <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) system is one of energy conversion methods to generate electricity from <span class="hlt">ocean</span> thermal energy. For OC-OTEC system, steam evaporated from the surface seawater due to flash evaporation drives the turbine. At that time, dissolved gas such as air is introduced into the low-pressure system (OC-OTEC system) as the non-condensable gas, which degrades the performance of condensation heat transfer. In this paper, a small scale OC-OTEC experimental unit experimentally investigates the effect of non-condensable gas on the heat transfer performance in a condenser. The experimental results are discussed in comparison with theoretical estimation by Sparrow-Lin method. It is shown that the condensation is occupied by heat and mass transfer near a condensation surface and that the condensation efficiency is affected by exhaust quantity of non-condensable gas at relative high concentration ratio of condensable gas.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989asme.conf....1P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989asme.conf....1P"><span>Experiments on oxygen desorption from surface warm seawater under <span class="hlt">Open</span>-Cycle <span class="hlt">Ocean</span> Thermal Energy Conversion (OC-OTEC) conditions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pesaran, Ahmad A.</p> <p>1989-12-01</p> <p>This paper reports the results of scoping deaeration experiments conducted with warm surface seawater under <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC). Concentrations of dissolved oxygen in seawater at three locations (in the supply <span class="hlt">water</span>, <span class="hlt">water</span> leaving a predeaerator, and discharge <span class="hlt">water</span> from an evaporator) were measured and used to estimate oxygen desorption levels. The results suggest that 7 pct to 60 pct of dissolved oxygen in the supply <span class="hlt">water</span> was desorbed from seawater in the predeaerator for pressures ranging from 9 to 35 kPa. Bubble injection in the upcomer increased the oxygen desorption rate by 20 pct to 60 pct. The dependence of oxygen desorption with flow rate could not be determined. The data also indicated that at typical OC-OTEC evaporator pressures when flashing occurred, 75 pct to 95 pct of dissolved oxygen was desorbed overall from the warm seawater. The uncertainty in results is larger than one would desire. These uncertainties are attributed to the uncertainties and difficulties in the dissolved oxygen measurements. Methods to improve the measurements for future gas desorption studies for warm surface and cold deep seawater under OC-OTEC conditions are recommended.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/7024705','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/7024705"><span>Experiments on oxygen desorption from surface warm seawater under <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Pesaran, A A</p> <p>1989-12-01</p> <p>This paper reports the results of scoping deaeration experiments conducted with warm surface seawater under <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC). Concentrations of dissolved oxygen in seawater at three locations (in the supply <span class="hlt">water</span>, <span class="hlt">water</span> leaving a predeaerator, and discharge <span class="hlt">water</span> from an evaporator) were measured and used to estimate oxygen desorption levels. The results suggest that 7% to 60% of dissolved oxygen in the supply <span class="hlt">water</span> was desorbed from seawater in the predeaerator for pressures ranging from 9 to 35 kPa. Bubble injection in the upcomer increased the oxygen desorption rate by 20% to 60%. The dependence of oxygen desorption with flow rate could not be determined. The data also indicated that at typical OC-OTEC evaporator pressures when flashing occurred, 75% to 95% of dissolved oxygen was desorbed overall from the warm seawater. The uncertainty in results is larger than one would desire. These uncertainties are attributed to the uncertainties and difficulties in the dissolved oxygen measurements. Methods to improve the measurements for future gas desorption studies for warm surface and cold deep seawater under OC-OTEC conditions are recommended. 14 refs., 5 figs., 2 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PrOce.120..230P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PrOce.120..230P"><span>Anthropogenic CO2 estimates in the Southern <span class="hlt">Ocean</span>: Storage partitioning in the different <span class="hlt">water</span> masses</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pardo, Paula C.; Pérez, F. F.; Khatiwala, S.; Ríos, A. F.</p> <p>2014-01-01</p> <p>The role of the Southern <span class="hlt">Ocean</span> (SO) remains a key issue in our understanding of the global carbon cycle and for predicting future climate change. A number of recent studies suggest that 30 to 40% of <span class="hlt">ocean</span> uptake of anthropogenic carbon (CANT) occurs in the SO, accompanied by highly efficient transport of CANT by intermediate-depth <span class="hlt">waters</span> out of that region. In contrast, storage of CANT in deep and bottom layers is still an <span class="hlt">open</span> question. Significant discrepancies can be found between results from several indirect techniques and <span class="hlt">ocean</span> models. Even though reference methodologies state that CANT concentrations in deep and bottom layers of the SO are negligible, recent results from tracer-based methods and <span class="hlt">ocean</span> models as well as accurate measurements of 39Ar, CCl4 and CFCs along the continental slope and in the Antarctic deep and bottom <span class="hlt">waters</span> contradict this conclusion. The role of the SO in the uptake, storage and transport of CANT has proved to be really important for the global <span class="hlt">ocean</span> and there is a need for agreement between the different techniques. A CO2-data-based ("back-calculation") method, the CT0 method, was developed with the aim of obtaining more accurate CANT concentration and inventory estimates in the SO region (south of 45°S). Data from the GLODAP (Global <span class="hlt">Ocean</span> Data Analysis Project) and CARINA databases were used. The CT0 method tries to reduce at least two of the main caveats attributed to the back-calculation methods: the need for a better definition of <span class="hlt">water</span> mass mixing and, most importantly, the unsteady state of the air-sea CO2 disequilibrium (ΔCdis) term. <span class="hlt">Water</span> mass mixing was computed on the basis of results from an extended Optimum Multi-Parametric (eOMP) analysis applied to the main <span class="hlt">water</span> masses of the SO. Recently published parameterizations were used to obtain more reliable values of ΔCdis and also of preformed alkalinity. The variability of the ΔCdis term (δCdis) was approximated using results from an <span class="hlt">ocean</span> carbon cycle model</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/82979','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/82979"><span>Successful <span class="hlt">water</span> reuse in <span class="hlt">open</span> recirculating cooling systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Vaska, M.; Lee, B.</p> <p>1994-12-31</p> <p><span class="hlt">Water</span> reuse in <span class="hlt">open</span> recirculating cooling <span class="hlt">water</span> systems is becoming increasingly prevalent in industry. Reuse can incorporate a number of varied approaches with the primary goal being <span class="hlt">water</span> conservation. Market forces driving this trend include scarcity of fresh <span class="hlt">water</span> makeup sources and higher costs associated with pretreatment of natural <span class="hlt">waters</span>. Utilization of reuse <span class="hlt">water</span> for cooling tower makeup has especially detrimental effects on corrosion and deposit rates. Additionally, once the reuse <span class="hlt">water</span> is cycled and treated with inhibitors, dispersants and microbiocides, acceptability for discharge to a public waterway can be a concern. The task for <span class="hlt">water</span> treatment suppliers is to guide industry in the feasibility and procedures for successfully achieving these goals. This paper focuses particularly on reuse of municipal wastewater for cooling tower makeup and explores techniques which have been found especially effective. Case histories are described where these concepts have been successfully applied in practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4585736','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4585736"><span>Fast Episodes of West-Mediterranean-Tyrrhenian <span class="hlt">Oceanic</span> <span class="hlt">Opening</span> and Revisited Relations with Tectonic Setting</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Savelli, Carlo</p> <p>2015-01-01</p> <p>Extension and calc-alkaline volcanism of the submerged orogen of alpine age (OAA) initiated in Early Oligocene (~33/32 Ma) and reached the stage of <span class="hlt">oceanic</span> <span class="hlt">opening</span> in Early-Miocene (Burdigalian), Late-Miocene and Late-Pliocene. In the Burdigalian (~20–16 Ma) period of widespread volcanism of calcalkaline type on the margins of <span class="hlt">oceanic</span> domain, seafloor spreading originated the deep basins of north Algeria (western part of OAA) and Sardinia/Provence (European margin). Conversely, when conjugate margins’ volcanism has been absent or scarce seafloor spreading formed the plains Vavilov (7.5–6.3 Ma) and Marsili (1.87–1.67 Ma) within OAA eastern part (Tyrrhenian Sea). The contrast between occurrence and lack of margin’s igneous activity probably implies the diversity of the geotectonic setting at the times of <span class="hlt">oceanization</span>. It appears that the Burdigalian calcalkaline volcanism on the continental margins developed in the absence of subduction. The WNW-directed subduction of African plate probably commenced at ~16/15 Ma (waning Burdigalian seafloor spreading) after ~18/16 Ma of rifting. Space-time features indicate that calcalkaline volcanism is not linked only to subduction. From this view, temporal gap would exist between the steep subduction beneath the Apennines and the previous, flat-type plunge of European plate with opposite direction producing the OAA accretion and double vergence. PMID:26391973</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26391973','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26391973"><span>Fast Episodes of West-Mediterranean-Tyrrhenian <span class="hlt">Oceanic</span> <span class="hlt">Opening</span> and Revisited Relations with Tectonic Setting.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Savelli, Carlo</p> <p>2015-09-22</p> <p>Extension and calc-alkaline volcanism of the submerged orogen of alpine age (OAA) initiated in Early Oligocene (~33/32 Ma) and reached the stage of <span class="hlt">oceanic</span> <span class="hlt">opening</span> in Early-Miocene (Burdigalian), Late-Miocene and Late-Pliocene. In the Burdigalian (~20-16 Ma) period of widespread volcanism of calcalkaline type on the margins of <span class="hlt">oceanic</span> domain, seafloor spreading originated the deep basins of north Algeria (western part of OAA) and Sardinia/Provence (European margin). Conversely, when conjugate margins' volcanism has been absent or scarce seafloor spreading formed the plains Vavilov (7.5-6.3 Ma) and Marsili (1.87-1.67 Ma) within OAA eastern part (Tyrrhenian Sea). The contrast between occurrence and lack of margin's igneous activity probably implies the diversity of the geotectonic setting at the times of <span class="hlt">oceanization</span>. It appears that the Burdigalian calcalkaline volcanism on the continental margins developed in the absence of subduction. The WNW-directed subduction of African plate probably commenced at ~16/15 Ma (waning Burdigalian seafloor spreading) after ~18/16 Ma of rifting. Space-time features indicate that calcalkaline volcanism is not linked only to subduction. From this view, temporal gap would exist between the steep subduction beneath the Apennines and the previous, flat-type plunge of European plate with opposite direction producing the OAA accretion and double vergence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatSR...514271S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatSR...514271S"><span>Fast Episodes of West-Mediterranean-Tyrrhenian <span class="hlt">Oceanic</span> <span class="hlt">Opening</span> and Revisited Relations with Tectonic Setting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Savelli, Carlo</p> <p>2015-09-01</p> <p>Extension and calc-alkaline volcanism of the submerged orogen of alpine age (OAA) initiated in Early Oligocene (~33/32 Ma) and reached the stage of <span class="hlt">oceanic</span> <span class="hlt">opening</span> in Early-Miocene (Burdigalian), Late-Miocene and Late-Pliocene. In the Burdigalian (~20-16 Ma) period of widespread volcanism of calcalkaline type on the margins of <span class="hlt">oceanic</span> domain, seafloor spreading originated the deep basins of north Algeria (western part of OAA) and Sardinia/Provence (European margin). Conversely, when conjugate margins’ volcanism has been absent or scarce seafloor spreading formed the plains Vavilov (7.5-6.3 Ma) and Marsili (1.87-1.67 Ma) within OAA eastern part (Tyrrhenian Sea). The contrast between occurrence and lack of margin’s igneous activity probably implies the diversity of the geotectonic setting at the times of <span class="hlt">oceanization</span>. It appears that the Burdigalian calcalkaline volcanism on the continental margins developed in the absence of subduction. The WNW-directed subduction of African plate probably commenced at ~16/15 Ma (waning Burdigalian seafloor spreading) after ~18/16 Ma of rifting. Space-time features indicate that calcalkaline volcanism is not linked only to subduction. From this view, temporal gap would exist between the steep subduction beneath the Apennines and the previous, flat-type plunge of European plate with opposite direction producing the OAA accretion and double vergence.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150003055','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150003055"><span><span class="hlt">Water</span> Distribution in the Continental and <span class="hlt">Oceanic</span> Upper Mantle</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Peslier, Anne H.</p> <p>2015-01-01</p> <p>Nominally anhydrous minerals such as olivine, pyroxene and garnet can accommodate tens to hundreds of ppm H2O in the form of hydrogen bonded to structural oxygen in lattice defects. Although in seemingly small amounts, this <span class="hlt">water</span> can significantly alter chemical and physical properties of the minerals and rocks. <span class="hlt">Water</span> in particular can modify their rheological properties and its distribution in the mantle derives from melting and metasomatic processes and lithology repartition (pyroxenite vs peridotite). These effects will be examined here using Fourier transform infrared spectrometry (FTIR) <span class="hlt">water</span> analyses on minerals from mantle xenoliths from cratons, plume-influenced cratons and <span class="hlt">oceanic</span> settings. In particular, our results on xenoliths from three different cratons will be compared. Each craton has a different <span class="hlt">water</span> distribution and only the mantle root of Kaapvaal has evidence for dry olivine at its base. This challenges the link between olivine <span class="hlt">water</span> content and survival of Archean cratonic mantle, and questions whether xenoliths are representative of the whole cratonic mantle. We will also present our latest data on Hawaii and Tanzanian craton xenoliths which both suggest the intriguing result that mantle lithosphere is not enriched in <span class="hlt">water</span> when it interacts with melts from deep mantle upwellings (plumes).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18365803','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18365803"><span>Effect of the South Bay <span class="hlt">Ocean</span> Outfall (SBOO) on <span class="hlt">ocean</span> beach <span class="hlt">water</span> quality near the USA-Mexico border.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gersberg, Richard; Tiedge, Jürgen; Gottstein, Dana; Altmann, Sophie; Watanabe, Kayo; Lüderitz, Volker</p> <p>2008-04-01</p> <p>In early 1999, primary treatment and discharge of sewage from Tijuana, Mexico (approximately 95 million liters per day) began through South Bay <span class="hlt">Ocean</span> Outfall (SBOO) into the <span class="hlt">ocean</span> 4.3 km offshore. In this study, statistical comparisons were made of the bacterial <span class="hlt">water</span> quality (total and fecal coliforms and enterococci densities) of the <span class="hlt">ocean</span>, both before and after discharge of sewage to the SBOO began, so that the effect of this <span class="hlt">ocean</span> discharge on nearshore <span class="hlt">ocean</span> <span class="hlt">water</span> quality could be quantitatively assessed. The frequency of exceedence of bacterial indicator thresholds was statistically analyzed for 11 shore (surfzone) stations throughout US and Mexico using the Fisher's exact test, for the years before (1995-1998) as compared to after the SBOO discharge began (1999-2003). Only four of the 11 shoreline stations (S2, S3, S11, and S12) showed significant improvement (decreased frequency of exceedence of bacterial indicator thresholds) after SBOO discharge began.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3197170','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3197170"><span>Enrichment and characterization of ammonia-oxidizing archaea from the <span class="hlt">open</span> <span class="hlt">ocean</span>: phylogeny, physiology and stable isotope fractionation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Santoro, Alyson E; Casciotti, Karen L</p> <p>2011-01-01</p> <p>Archaeal genes for ammonia oxidation are widespread in the marine environment, but direct physiological evidence for ammonia oxidation by marine archaea is limited. We report the enrichment and characterization of three strains of pelagic ammonia-oxidizing archaea (AOA) from the North Pacific <span class="hlt">Ocean</span> that have been maintained in laboratory culture for over 3 years. Phylogenetic analyses indicate the three strains belong to a previously identified clade of <span class="hlt">water</span> column-associated AOA and possess 16S ribosomal RNA genes and ammonia monooxygenase subunit a (amoA) genes highly similar (98–99% identity) to those recovered in DNA and complementary DNA clone libraries from the <span class="hlt">open</span> <span class="hlt">ocean</span>. The strains grow in natural seawater-based liquid medium while stoichiometrically converting ammonia (NH3) to nitrite (NO2−). Ammonia oxidation by the enrichments is only partially inhibited by allylthiourea at concentrations known to completely inhibit cultivated ammonia-oxidizing bacteria. The three strains were used to determine the nitrogen stable isotope effect (15ɛNH3) during archaeal ammonia oxidation, an important parameter for interpreting stable isotope ratios in the environment. Archaeal 15ɛNH3 ranged from 13‰ to 41‰, within the range of that previously reported for ammonia-oxidizing bacteria. Despite low amino acid identity between the archaeal and bacterial Amo proteins, their functional diversity as captured by 15ɛNH3 is similar. PMID:21562601</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4826011','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4826011"><span>Diatom Phytochromes Reveal the Existence of Far-Red-Light-Based Sensing in the <span class="hlt">Ocean[OPEN</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Enomoto, Gen; Bouly, Jean-Pierre; Thaler, Michael; Malviya, Shruti; Bernardes, Juliana Silva; Rappaport, Fabrice; Gentili, Bernard; Huysman, Marie J.J.; Carbone, Alessandra; Bowler, Chris; Ikeuchi, Masahiko; Falciatore, Angela</p> <p>2016-01-01</p> <p>The absorption of visible light in aquatic environments has led to the common assumption that aquatic organisms sense and adapt to penetrative blue/green light wavelengths but show little or no response to the more attenuated red/far-red wavelengths. Here, we show that two marine diatom species, Phaeodactylum tricornutum and Thalassiosira pseudonana, possess a bona fide red/far-red light sensing phytochrome (DPH) that uses biliverdin as a chromophore and displays accentuated red-shifted absorbance peaks compared with other characterized plant and algal phytochromes. Exposure to both red and far-red light causes changes in gene expression in P. tricornutum, and the responses to far-red light disappear in DPH knockout cells, demonstrating that P. tricornutum DPH mediates far-red light signaling. The identification of DPH genes in diverse diatom species widely distributed along the <span class="hlt">water</span> column further emphasizes the ecological significance of far-red light sensing, raising questions about the sources of far-red light. Our analyses indicate that, although far-red wavelengths from sunlight are only detectable at the <span class="hlt">ocean</span> surface, chlorophyll fluorescence and Raman scattering can generate red/far-red photons in deeper layers. This study <span class="hlt">opens</span> up novel perspectives on phytochrome-mediated far-red light signaling in the <span class="hlt">ocean</span> and on the light sensing and adaptive capabilities of marine phototrophs. PMID:26941092</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMPP33B2313C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMPP33B2313C"><span>Fish Productivity in <span class="hlt">Open-Ocean</span> Gyre Systems in the Late Oligocene and Miocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cuevas, J. M.; Sibert, E. C.; Norris, R. D.</p> <p>2015-12-01</p> <p>Understanding how marine ecosystems respond to climate change is very important as we continue to warm the climate. Fish represent a critical protein source for a significant portion of the global population, and as such, an understanding of fish production and its interactions with climate change may help better prepare for the future. Ichthyoliths, fossil fish teeth and shark scales, are a novel fossil group which can be used as an indicator for fish productivity. Several important climate events occurred during the Miocene (7 to 23 Ma), including the Middle Miocene Climatic Optimum. Here we reconstruct fish production from across the Miocene from Pacific and Atlantic <span class="hlt">Ocean</span> gyres. South Atlantic samples, from Deep Sea Drilling Program (DSDP) Site 522 spanning from 30 to 20 Ma, show fairly variable numbers in the Oligocene (ranging from 100 to 800 ich/cm2/yr), but stabilization in the Early Miocene (around 400 ich/cm2/yr), suggesting that the beginning of the Miocene brought consistent conditions for fish production. In the North Pacific, our record from <span class="hlt">Ocean</span> Drilling Program (ODP) Site 886 shows a distinct crash in fish productivity at 11 Ma, from 3500 ich/cm2/yr to a steady decline around 100 ich/cm2/yr for the next million years. This crash is followed by a marked increase in the presence of diatoms and biogenous opal. This is somewhat surprising, since in modern <span class="hlt">oceanic</span> systems, an increase in diatoms and other large-celled phytoplankton is associated with shorter, more efficient food chains and higher levels of fish. It is also interesting to note that denticles remain consistently low at both sites, indicating consistently low shark populations through this time period. Together, these results suggest that the Late Oligocene and Miocene was a time of variable fish production and provide a window into understanding of dynamic ecosystem changes through the Miocene in <span class="hlt">open-ocean</span> gyre ecosystems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..1711616B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..1711616B"><span>FixO3: Advancement towards <span class="hlt">Open</span> <span class="hlt">Ocean</span> Observatory Data Management Harmonisation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Behnken, Andree; Pagnani, Maureen; Huber, Robert; Lampitt, Richard</p> <p>2015-04-01</p> <p>Since 2002 there has been a sustained effort, supported as European framework projects, to harmonise both the technology and the data management of <span class="hlt">Open</span> <span class="hlt">Ocean</span> fixed observatories run by European nations. FixO3 started in September 2013, and for 3 more years will coordinate the convergence of data management best practice across a constellation of moorings in the Atlantic, in both hemispheres, and in the Mediterranean. To ensure the continued existence of these unique sources of oceanographic data as sustained observatories it is vital to improve access to the data collected, both in terms of methods of presentation, real-time availability, long-term archiving and quality assurance. The data management component of FixO3 improves access to marine observatory data by harmonising data management standards, formats and workflows covering the complete life cycle of data from real time data acquisition to long-term archiving. Legal and data policy aspects have been examined and discussed to identify transnational barriers to <span class="hlt">open</span>-access to marine observatory data. As a result, a harmonised FixO3 data policy was drafted, which provides a formal basis for data exchange between FixO3 infrastructures, and also enables <span class="hlt">open</span> access to data for the general public. FixO3 interacts with other European infrastructures such as EMODnet, SeaDataNet, PANGAEA, and especially aims to harmonise efforts with <span class="hlt">Ocean</span>Sites and My<span class="hlt">Ocean</span>. The project landing page (www.fixo3.eu) offers detailed information about every observatory as well as data visualisations and direct downloads. In addition to this, metadata for all FixO3 - relevant data are available from the searchable FixO3 metadata catalogue, which is also accessible from the project web page. This catalogue is hosted by PANGAEA and receives updates in regular intervals. The FixO3 Standards & Services registry ties in with the GEOSS Components and Services Registry (CSR) and provides additional observatory information. The data management</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMOS53C1997R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMOS53C1997R"><span>Changing carbonate chemistry in <span class="hlt">ocean</span> <span class="hlt">waters</span> surrounding coral reefs in the CMIP5 ensemble</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ricke, K.; Schneider, K.; Cao, L.; Caldeira, K.</p> <p>2012-12-01</p> <p>Coral reefs comprise some of the most biodiverse ecosystems in the world. Today they are threatened by a number of stressors, including pollution, bleaching from global warming and <span class="hlt">ocean</span> acidification. In this study, we focus on the implications of <span class="hlt">ocean</span> acidification for the <span class="hlt">open</span> <span class="hlt">ocean</span> chemistry surrounding coral reefs. We use results from 13 Earth System Models included in the Coupled Model Intercomparison Project 5 (CMIP5) to examine the changing aragonite saturations (Ωa) of <span class="hlt">open</span> <span class="hlt">ocean</span> <span class="hlt">waters</span> surrounding approximately 6,000 coral reefs. These 13 Earth System Models participating in CMIP5 each have interactive <span class="hlt">ocean</span> biogeochemistry models that output state variables including DIC, alkalinity, SST, and salinity. Variation in these values were combined with values from the GLODAP database to calculate aragonite, the form of calcium carbonate that corals use to make their skeletons. We used reef locations from ReefBase that were within one degree (in latitude or longitude) of <span class="hlt">water</span> masses represented both in the GLODAP database and in the climate models. Carbonate chemistry calculations were performed by Dr. James C. Orr (IPSL) as part of a separate study. We find that in preindustrial times, 99.9 % of coral reefs were located in regions of the <span class="hlt">ocean</span> with aragonite saturations of 3.5 or more. The saturation threshold for viable reef ecosystems in uncertain, but the pre-industrial distribution of <span class="hlt">water</span> chemistry surrounding coral reefs may nevertheless provide some indication of viability. We examine the fate of coral reefs in the context of several potential aragonite saturation thresholds, i.e., when Ωa_crit equals 3, 3.25, or 3.5. We show that under a business-as-usual scenario Representative Concentration Pathway (RCP) 8.5, the specific value of Ωa_crit does not affect the long-term fate of coral reefs -- by the end of the 21st century, no coral reef considered is surrounded by <span class="hlt">water</span> with Ωa> 3. However, under scenarios with significant CO2 emissions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1988GeoRL..15.1393C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1988GeoRL..15.1393C"><span>Sulfide in surface <span class="hlt">waters</span> of the western Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cutter, Gregory A.; Krahforst, Christian F.</p> <p>1988-11-01</p> <p>Using newly developed techniques, some preliminary data on hydrogen sulfide in surface <span class="hlt">waters</span> of the western Atlantic have been obtained. Concentrations of total sulfide range from <0.1 to 1.1 nmol/L, and vary on a diel basis. At these concentrations, sulfide may affect the cycling of several trace metals via the formation of stable complexes. Production of sulfide in oxygenated seawater may occur through the hydrolysis of carbonyl sulfide or by sulfate reduction within macroscopic particles in the <span class="hlt">water</span> column. Removal mechanisms can include oxidation, complexation with particulate trace metals, and metal sulfide precipitation. However, the temporal and spatial distributions suggest a complex set of processes governing the behavior of sulfide in the surface <span class="hlt">ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015OcScD..12.1187D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015OcScD..12.1187D"><span><span class="hlt">Ocean</span> modelling for aquaculture and fisheries in Irish <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dabrowski, T.; Lyons, K.; Cusack, C.; Casal, G.; Berry, A.; Nolan, G. D.</p> <p>2015-06-01</p> <p>The Marine Institute, Ireland, runs a suite of operational regional and coastal <span class="hlt">ocean</span> models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. A shellfish model that includes growth and physiological interactions of mussels with the ecosystem and is fully embedded in the 3-D numerical modelling framework has been developed at the Marine Institute. This shellfish model has a microbial module designed to predict levels of coliform contamination in mussels. This model can also be used to estimate the carrying capacity of embayments, assess impacts of pollution on aquaculture grounds and help to classify shellfish <span class="hlt">waters</span>. The physical coastal model of southwest Ireland provides a three day forecast of shelf <span class="hlt">water</span> movement in the region. This is assimilated into a new harmful algal bloom alert system used to inform end-users of potential toxic shellfish events and high biomass blooms that include fish killing species. Further services include the use of models to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the marine fisheries resources. This paper demonstrates that <span class="hlt">ocean</span> models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016OcSci..12..101D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016OcSci..12..101D"><span><span class="hlt">Ocean</span> modelling for aquaculture and fisheries in Irish <span class="hlt">waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dabrowski, T.; Lyons, K.; Cusack, C.; Casal, G.; Berry, A.; Nolan, G. D.</p> <p>2016-01-01</p> <p>The Marine Institute, Ireland, runs a suite of operational regional and coastal <span class="hlt">ocean</span> models. Recent developments include several tailored products that focus on the key needs of the Irish aquaculture sector. In this article, an overview of the products and services derived from the models are presented. The authors give an overview of a shellfish model developed in-house and that was designed to predict the growth, the physiological interactions with the ecosystem, and the level of coliform contamination of the blue mussel. As such, this model is applicable in studies on the carrying capacity of embayments, assessment of the impacts of pollution on aquaculture grounds, and the determination of shellfish <span class="hlt">water</span> classes. Further services include the assimilation of the model-predicted shelf <span class="hlt">water</span> movement into a new harmful algal bloom alert system used to inform end users of potential toxic shellfish events and high biomass blooms that include fish-killing species. Models are also used to identify potential sites for offshore aquaculture, to inform studies of potential cross-contamination in farms from the dispersal of planktonic sea lice larvae and other pathogens that can infect finfish, and to provide modelled products that underpin the assessment and advisory services on the sustainable exploitation of the resources of marine fisheries. This paper demonstrates that <span class="hlt">ocean</span> models can provide an invaluable contribution to the sustainable blue growth of aquaculture and fisheries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15666678','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15666678"><span>Declining extent of <span class="hlt">open-water</span> refugia for top predators in Baffin Bay and adjacent <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Heide-Jørgensen, Mads Peter; Laidre, Kristin L</p> <p>2004-12-01</p> <p>Global climate change is expected to severely impact Arctic ecosystems, yet predictions of impacts are complicated by region-specific patterns and nonuniform trends. Twentyfour <span class="hlt">open-water</span> overwintering areas (or "microhabitats") were identified to be of particular importance for eight seabird and marine mammal species in the eastern Canadian High Arctic and Baffin Bay. Localized trends in the available fraction of <span class="hlt">open-water</span> were examined in March during 1979--2001, derived from approximate sea ice concentrations from satellite-based microwave telemetry. Declines in the fraction of <span class="hlt">open-water</span> were identified at microhabitats in Baffin Bay, Davis Strait, coastal West Greenland, and Lancaster Sound. Increases in <span class="hlt">open-water</span> were observed in Hudson Bay, Hudson Strait, and Foxe Basin. The biological importance of each microhabitat was examined based on species distribution and abundance. Potential consequences of reduced <span class="hlt">open-water</span> for top marine predators include impacts on foraging efficiency and oxygen and prey availability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.P11A2055F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.P11A2055F"><span>Where did the <span class="hlt">Water</span> in Earth's <span class="hlt">Oceans</span> Come from?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Freund, F. T.; Freund, M. M.</p> <p>2015-12-01</p> <p>How did Earth get the <span class="hlt">water</span> to fill its <span class="hlt">oceans</span>? Upper mantle minerals, in particular olivine, pyroxenes and others, retrieved at the Earth's surface, have consistently been found to contain low hydroxyl concentrations, indicative of a low to very low solute H2O contents. This has been interpreted for decades to mean that the upper mantle of the early Earth may not have had enough <span class="hlt">water</span> to fill the <span class="hlt">oceans</span> through volcanic and other degassing. To overcome this dilemma, large-scale cometary impacts are thought to have been necessary to supply the missing <span class="hlt">water</span>. This interpretation is based on a misinterpretation of laboratory data obtained primarily by infrared absorption but also SIMS and related techniques. This interpretation disregards a pervasive redox conversion that takes place in the solid state, during cooling, changing pairs of solute hydroxyls into peroxy plus H2. This redox conversion simply rearranges electrons within hydroxyl pairs. It takes place under thermodynamic non-equilibrium conditions, at temperatures so low that diffusional processes in the mineral matrix are already frozen. As a result every mineral and rock brought to the surface of the Earth and retrievable for analysis has undergone this redox conversion. Its importance is that it produces molecular H2, interstitial in the matrix of minerals, difficult to assess analytically. It produces peroxy defects, which have been overlooked for a long time. H2 molecules may diffuse out of mineral grains, leaving behind the peroxy as a memory of the former solute <span class="hlt">water</span> content. In order to fully assess the true solute H2O content in the Earth's upper mantle it is necessary to take the peroxy contents into consideration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009AGUFM.V44C..05V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009AGUFM.V44C..05V"><span>Little Drops of (<span class="hlt">Ocean</span>) <span class="hlt">Water</span>, Little Grains of (Zircon) Sand</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Valley, J. W.; Grimes, C. B.; Ortiz, D. M.; Ushikubo, T.; Bouvier, A.; Kita, N.; Cavosie, A. J.</p> <p>2009-12-01</p> <p>Little detrital grains of zircon in the ~3 Ga Jack Hills metaconglomerate yield concordant U-Pb ages up to 4.4 Ga and provide the only direct evidence of conditions on the Early Earth. Parent rocks were destroyed by weathering and erosion; ages >4 Ga are known only from isolated zircons. These zircons and their mineral inclusions represent very small rocks and analysis is a technical challenge. Zircons have been imaged by CL and BSE, and analyzed for U-Pb age; isotope ratios of O, Li, Si, & Hf; trace elements; and inclusions. Ion microprobes in many labs have proven unique capability to unlock the evidence in these small, precious, zoned “time capsules”. What is the genesis of the pre-4 Ga zircon suite? In situ analyses argue against meteorites (δ18O, Δ17O) including the Moon (δ18O, Ti), and also the Earth’s mantle (δ18O, REEs, U+Th, Li, δ7Li). The question of <span class="hlt">oceanic</span> vs. continental crust is more contentious. Zircons are common in <span class="hlt">oceanic</span> plagiogranites and oxide gabbros leading to speculation that the pre-4 Ga samples originated in dominantly mafic crust. However, <span class="hlt">oceanic</span> zircons are significantly different in trace elements (Grimes et al. 2007); [Li] and δ7Li (<0.1ppm vs. >10ppm, Ushikubo et al. 2008, Bouvier et al. 2009); and δ18O (5.2±0.5‰, 221 zircons from 40 <span class="hlt">oceanic</span> plagiogranites and gabbros, Cavosie et al. 2009, Grimes et al. 2009). There is no known modern <span class="hlt">oceanic</span> or ophiolitic analog for the pre-4 Ga zircons. In contrast, similarities are strong to Archean continental crust, esp. TTGs. We see no compelling evidence for true granites (many gabbros have similar Ti-in-zircon; inclusions in zircon are typically altered: Δ18O(Qt-Zrc)=3.2-8‰, muscovites have 0.03-1.03wt‰ Cr2O3). Was the surface of Early Earth Hadean? Mildly elevated values of δ18O(Zrc) (6 to 7.5) indicate low temperature interaction of protoliths with liquid <span class="hlt">water</span> during weathering or diagenesis. Thus, steam atmospheres condensed to liquid <span class="hlt">water</span> <span class="hlt">oceans</span> (possibly ice</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011AGUFM.C53F..05P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011AGUFM.C53F..05P"><span>Accurate numerical forward model for optimal retracking of SIRAL2 SAR echoes over <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Phalippou, L.; Demeestere, F.</p> <p>2011-12-01</p> <p>The SAR mode of SIRAL-2 on board Cryosat-2 has been designed to measure primarily sea-ice and continental ice (Wingham et al. 2005). In 2005, K. Raney (KR, 2005) pointed out the improvements brought by SAR altimeter for <span class="hlt">open</span> <span class="hlt">ocean</span>. KR results were mostly based on 'rule of thumb' considerations on speckle noise reduction due to the higher PRF and to speckle decorrelation after SAR processing. In 2007, Phalippou and Enjolras (PE,2007) provided the theoretical background for optimal retracking of SAR echoes over <span class="hlt">ocean</span> with a focus on the forward modelling of the power-waveforms. The accuracies of geophysical parameters (range, significant wave heights, and backscattering coefficient) retrieved from SAR altimeter data were derived accounting for SAR echo shape and speckle noise accurate modelling. The step forward to optimal retracking using numerical forward model (NFM) was also pointed out. NFM of the power waveform avoids analytical approximation, a warranty to minimise the geophysical dependent biases in the retrieval. NFM have been used for many years, in operational meteorology in particular, for retrieving temperature and humidity profiles from IR and microwave radiometers as the radiative transfer function is complex (Eyre, 1989). So far this technique was not used in the field of <span class="hlt">ocean</span> conventional altimetry as analytical models (e.g. Brown's model for instance) were found to give sufficient accuracy. However, although NFM seems desirable even for conventional nadir altimetry, it becomes inevitable if one wish to process SAR altimeter data as the transfer function is too complex to be approximated by a simple analytical function. This was clearly demonstrated in PE 2007. The paper describes the background to SAR data retracking over <span class="hlt">open</span> <span class="hlt">ocean</span>. Since PE 2007 improvements have been brought to the forward model and it is shown that the altimeter on-ground and in flight characterisation (e.g antenna pattern range impulse response, azimuth impulse response</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=330319','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=330319"><span><span class="hlt">Open</span> inlet conversion: <span class="hlt">Water</span> quality benefits of two designs</span></a></p> <p><a target="_blank" href="https://www.ars.usda.gov/research/publications/find-a-publication/">USDA-ARS?s Scientific Manuscript database</a></p> <p></p> <p></p> <p><span class="hlt">Open</span> surface inlets that connect to subsurface tile drainage systems provide a direct pathway for movement of sediment, nutrients, and agrochemicals to surface <span class="hlt">waters</span>. This study was conducted to determine the reduction in drainage effluent total suspended sediment (TSS) and phosphorus (P) concentr...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006GeCoA..70.2790R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006GeCoA..70.2790R"><span>Enhancement and inhibition of iron photoreduction by individual ligands in <span class="hlt">open</span> <span class="hlt">ocean</span> seawater</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rijkenberg, Micha J. A.; Gerringa, Loes J. A.; Carolus, Vicky E.; Velzeboer, Ilona; de Baar, Hein J. W.</p> <p>2006-06-01</p> <p>In laboratory experiments, we investigated the effect of five individual Fe-binding ligands: phaeophytin, ferrichrome, desferrioxamine B (DFOB), inositol hexaphosphate (phytic acid), and protoporphyrin IX (PPIX) on the Fe(II) photoproduction using seawater of the <span class="hlt">open</span> Southern <span class="hlt">Ocean</span>. Addition of 10-100 nM Fe(III) to <span class="hlt">open</span> Southern <span class="hlt">Ocean</span> seawater without the model ligands and containing; 1.1 nM dissolved Fe(III), 1.75 ± 0.28 equivalents of nM Fe of natural ligands with a conditional stability constant (log K') of 21.75 ± 0.34 and a concentration DOC of 86.8 ± 1.13 μM C leads to the formation of amorphous Fe(III) hydroxides. These amorphous Fe(III) hydroxides are the major source for the photoproduction of Fe(II). The addition of the model ligands changed the Fe(II) photoproduction considerably and in various ways. Phaeophytin showed higher Fe(II) photoproduction than ferrichrome and the control, i.e., amorphous Fe(III) hydroxides. Additions of phytic acid between 65 and 105 nM increased the concentration of photoproduced Fe(II) with 0.16 nM Fe(II) per nM phytic acid, presumably due to the co-aggregation of Fe(III) and phytic acid leading via an increasing colloidal surface to an increasing photoreducible Fe(III) fraction. DFOB and PPIX strongly decreased the photoproduced Fe(II) concentration. The low Fe(II) photoproduction with DFOB confirmed reported observations that Fe(III) complexed to DFOB is photo-stable. The PPIX hardly binds Fe(III) in the <span class="hlt">open</span> Southern <span class="hlt">Ocean</span> seawater but decreased the photoproduced Fe(II) concentration by complexing the Fe(II) with a binding rate constant of kFe(II)PPIX = 1.04 × 10 -4 ± 1.53 × 10 -5 s -1 nM -1 PPIX. Subsequently, PPIX is suggested to act as a photosensitizing producer of superoxide, thus increasing the dark reduction of Fe(III) to Fe(II). Our research shows that the photochemistry of Fe(III) and the resulting photoproduced Fe(II) concentration is strongly depending on the identity of the Fe-binding organic ligands</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/495430','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/495430"><span>Modeling sea-<span class="hlt">water</span> intrusion with <span class="hlt">open</span> boundary conditions</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Padilla, F.; Cruz-Sanjulian, J.</p> <p>1997-07-01</p> <p>The present study concerns the application of a new numerical approach to describe the fresh-<span class="hlt">water/sea-water</span> relationships in coastal aquifers. Essentially, a solution to the partial differential equation governing the regional motion of a phreatic surface and the resulting interface between fresh <span class="hlt">water</span> and salt <span class="hlt">water</span> is analyzed by a Galerkin finite-element formulation. A single-phase steady numerical model was applied to approximate, with simple triangular elements, the regional behavior of a coastal aquifer under appropriate sinks, sources, Neumann, outflow face, and <span class="hlt">open</span> boundary conditions. On the one hand, outflow <span class="hlt">open</span> boundaries at the coastline were not treated with other classical boundary conditions, but instead with a formal numerical approach for <span class="hlt">open</span> boundaries inspired in this particular case by the Dupuit approximation of horizontal outflow at the boundary. The solution to this numerical model, together with the Ghyben-Herzberg principle, allows the correct simulation of fresh-<span class="hlt">water</span> heads and the position of the salt-<span class="hlt">water</span> interface for a steeply sloping coast. Although the solutions were precise and do not present classical numerical oscillations, this approach requires a previous solution with Dirichlet boundary conditions at the coastline in order to find a good convergence of the solution algorithm. On the other hand, the same precise results were obtained with a more restrictive <span class="hlt">open</span> boundary condition, similar in a way to the outflow face approach, which required less computer time, did not need a prior numerical solution and could be extended to different coastline conditions. The steady-state problem was solved for different hypothetical coastal aquifers and fresh-<span class="hlt">water</span> usage through three types of numerical tests.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012JGRD..117.7210N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012JGRD..117.7210N"><span>Eddy covariance measurements of the sea spray aerosol flux over the <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Norris, Sarah J.; Brooks, Ian M.; Hill, Martin K.; Brooks, Barbara J.; Smith, Michael H.; Sproson, David A. J.</p> <p>2012-04-01</p> <p>Direct eddy covariance measurements of size-segregated sea spray aerosol fluxes over the <span class="hlt">open</span> Atlantic <span class="hlt">Ocean</span> are presented, along with a source function derived from them for a wind speed range of 4 to 18 m s-1 and a size range of 0.176 < R80 < 6.61 μm. This is in broad agreement with other recent estimates of the source function over this size range but shows a more rapid decrease with size above R80 = 2 μm than most other functions. The measurements were made during a 3 week cruise in the North Atlantic as part of the UK contribution to the international Surface <span class="hlt">Ocean</span>-Lower Atmosphere Study (SOLAS) program. They utilized the new high-rate Compact Lightweight Aerosol Spectrometer Probe (CLASP), providing a 16-channel size spectrum (0.17 <Ramb < 9.5 μm) at 10 Hz, collocated with a sonic anemometer. The measurements demonstrate the high variability in sea spray aerosol flux compared with other air-sea fluxes, both between individual estimates and in the scales contributing to the flux.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMOS41E..01C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMOS41E..01C"><span>Air-sea Fluxes and Mode <span class="hlt">Waters</span> in an Eddy Resolving <span class="hlt">Ocean</span> Data Assimilating Southern <span class="hlt">Ocean</span> State Estimate (SOSE) (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cerovecki, I.; Talley, L. D.; Mazloff, M. R.</p> <p>2010-12-01</p> <p>An eddy-permitting data assimilating system, the Southern <span class="hlt">Ocean</span> State Estimate (SOSE), has been developed by Mazloff et al. (2010) to estimate the Southern <span class="hlt">Ocean</span> circulation in years 2005 and 2006. We assess the accuracy of SOSE air-sea heat and freshwater flux estimates by comparing them to widely used flux products (the National Center for Environmental Prediction-National Center for Atmospheric Reanalysis 1 (NCEP1), European Centre for Medium-Range Weather Forecasts operational model) and to a recently developed flux product constructed by Large and Yeager (2009). SOSE and Large and Yeager (2009) estimates show remarkable similarity in the large scale pattern of air-sea fluxes when compared to the NCEP1 fields that SOSE uses as an initial guess and constraint. Having verified that the accuracy of SOSE air-sea buoyancy flux estimate is satisfactory, we use SOSE fluxes and three-dimensional <span class="hlt">oceanic</span> fields to investigate Subantarctic Mode <span class="hlt">Water</span> (SAMW) formation and destruction by diapycnal buoyancy exchange at the <span class="hlt">ocean</span> surface and in the <span class="hlt">ocean</span> interior as well as identify and quantify SAMW transport pathways. Surface buoyancy fluxes produce on average 6.9 +/-1.6 Sv of Southeast Indian SAMW (SEISAMW) and 4.8 +/- 2.2 Sv of East Pacific SAMW, averaged over years 2005 and 2006. This transformation is largely compensated by diapycnal mixing in the <span class="hlt">ocean</span> interior where SAMW gets mostly transformed into denser <span class="hlt">water</span>, especially in the Pacific sector of the Southern <span class="hlt">Ocean</span>. There is also a net conversion of lighter thermocline <span class="hlt">water</span> into SAMW in the <span class="hlt">ocean</span> interior (occurring mostly in the Indian <span class="hlt">Ocean</span>), which is part of the shallow overturning. The zonally integrated export of SAMW across 30S is thus relatively small and on average equals approximately 3.5 Sv of (SEISAMW) and 2.0 Sv of East Pacific SAMW.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2010-title33-vol3/pdf/CFR-2010-title33-vol3-sec336-2.pdf','CFR'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2010-title33-vol3/pdf/CFR-2010-title33-vol3-sec336-2.pdf"><span>33 CFR 336.2 - Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2010&page.go=Go">Code of Federal Regulations, 2010 CFR</a></p> <p></p> <p>2010-07-01</p> <p>... material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. 336.2 Section 336.2 Navigation and Navigable <span class="hlt">Waters</span>... <span class="hlt">WATERS</span> OF THE U.S. AND <span class="hlt">OCEAN</span> <span class="hlt">WATERS</span> § 336.2 Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. (a) Applicable law. Section 103(a) of the ODA provides that the Corps of...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title33-vol3/pdf/CFR-2013-title33-vol3-sec336-2.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title33-vol3/pdf/CFR-2013-title33-vol3-sec336-2.pdf"><span>33 CFR 336.2 - Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-07-01</p> <p>... material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. 336.2 Section 336.2 Navigation and Navigable <span class="hlt">Waters</span>... <span class="hlt">WATERS</span> OF THE U.S. AND <span class="hlt">OCEAN</span> <span class="hlt">WATERS</span> § 336.2 Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. (a) Applicable law. Section 103(a) of the ODA provides that the Corps of...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title33-vol3/pdf/CFR-2011-title33-vol3-sec336-2.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title33-vol3/pdf/CFR-2011-title33-vol3-sec336-2.pdf"><span>33 CFR 336.2 - Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-07-01</p> <p>... material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. 336.2 Section 336.2 Navigation and Navigable <span class="hlt">Waters</span>... <span class="hlt">WATERS</span> OF THE U.S. AND <span class="hlt">OCEAN</span> <span class="hlt">WATERS</span> § 336.2 Transportation of dredged material for the purpose of disposal into <span class="hlt">ocean</span> <span class="hlt">waters</span>. (a) Applicable law. Section 103(a) of the ODA provides that the Corps of...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18992005','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18992005"><span><span class="hlt">Open-ocean</span> barriers to dispersal: a test case with the Antarctic Polar Front and the ribbon worm Parborlasia corrugatus (Nemertea: Lineidae).</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Thornhill, Daniel J; Mahon, Andrew R; Norenburg, Jon L; Halanych, Kenneth M</p> <p>2008-12-01</p> <p><span class="hlt">Open-ocean</span> environments provide few obvious barriers to the dispersal of marine organisms. Major currents and/or environmental gradients potentially impede gene flow. One system hypothesized to form an <span class="hlt">open-ocean</span> dispersal barrier is the Antarctic Polar Front, an area characterized by marked temperature change, deep <span class="hlt">water</span>, and the high-flow Antarctic Circumpolar current. Despite these potential isolating factors, several invertebrate species occur in both regions, including the broadcast-spawning nemertean worm Parborlasia corrugatus. To empirically test for the presence of an <span class="hlt">open-ocean</span> dispersal barrier, we sampled P. corrugatus and other nemerteans from southern South America, Antarctica, and the sub-Antarctic islands. Diversity was assessed by analyzing mitochondrial 16S rRNA and cytochrome c oxidase subunit I sequence data with Bayesian inference and tcs haplotype network analysis. Appropriate neutrality tests were also employed. Although our results indicate a single well-mixed lineage in Antarctica and the sub-Antarctic, no evidence for recent gene flow was detected between this population and South American P. corrugatus. Thus, even though P. corrugatus can disperse over large geographical distances, physical oceanographic barriers (i.e. Antarctic Polar Front and Antarctic Circumpolar Current) between continents have likely restricted dispersal over evolutionary time. Genetic distances and haplotype network analysis between South American and Antarctic/sub-Antarctic P. corrugatus suggest that these two populations are possibly two cryptic species.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26511427','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26511427"><span>To Madagascar and back: long-distance, return migration across <span class="hlt">open</span> <span class="hlt">ocean</span> by a pregnant female bull shark Carcharhinus leucas.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Lea, J S E; Humphries, N E; Clarke, C R; Sims, D W</p> <p>2015-12-01</p> <p>A large, pregnant, female bull shark Carcharhinus leucas was tracked migrating from Seychelles across <span class="hlt">open</span> <span class="hlt">ocean</span> to south-east Madagascar, c. 2000 km away, and back again. In Madagascar, the shark spent a prolonged period shallower than 5 m, consistent with entering estuarine habitat to pup, and upon return to Seychelles the shark was slender and no longer gravid. This represents an unprecedented return migration across the <span class="hlt">open</span> <span class="hlt">ocean</span> for a C. leucas and highlights the need for international collaboration to manage the regional C. leucas population sustainably.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70170185','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70170185"><span>An analysis of <span class="hlt">water</span> data systems to inform the <span class="hlt">Open</span> <span class="hlt">Water</span> Data Initiative</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Blodgett, David L.; Read, Emily K.; Lucido, Jessica M.; Slawecki, Tad; Young, Dwane</p> <p>2016-01-01</p> <p>Improving access to data and fostering <span class="hlt">open</span> exchange of <span class="hlt">water</span> information is foundational to solving <span class="hlt">water</span> resources issues. In this vein, the Department of the Interior's Assistant Secretary for <span class="hlt">Water</span> and Science put forward the charge to undertake an <span class="hlt">Open</span> <span class="hlt">Water</span> Data Initiative (OWDI) that would prioritize and accelerate work toward better <span class="hlt">water</span> data infrastructure. The goal of the OWDI is to build out the <span class="hlt">Open</span> <span class="hlt">Water</span> Web (OWW). We therefore considered the OWW in terms of four conceptual functions: <span class="hlt">water</span> data cataloging, <span class="hlt">water</span> data as a service, enriching <span class="hlt">water</span> data, and community for <span class="hlt">water</span> data. To describe the current state of the OWW and identify areas needing improvement, we conducted an analysis of existing systems using a standard model for describing distributed systems and their business requirements. Our analysis considered three OWDI-focused use cases—flooding, drought, and contaminant transport—and then examined the landscape of other existing applications that support the <span class="hlt">Open</span> <span class="hlt">Water</span> Web. The analysis, which includes a discussion of observed successful practices of cataloging, serving, enriching, and building community around <span class="hlt">water</span> resources data, demonstrates that we have made significant progress toward the needed infrastructure, although challenges remain. The further development of the OWW can be greatly informed by the interpretation and findings of our analysis.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990STIN...9119501Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990STIN...9119501Z"><span>Results of scoping tests for <span class="hlt">open</span>-cycle OTEC (<span class="hlt">Ocean</span> Thermal Energy Conversion) components operating with seawater</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zangrando, F.; Bharathan, D.; Green, H. J.; Link, H. F.; Parsons, B. K.; Parsons, J. M.; Pesaran, A. A.; Panchal, C. B.</p> <p>1990-09-01</p> <p>This report presents comprehensive documentation of the experimental research conducted on <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) components operating with seawater as a working fluid. The results of this research are presented in the context of previous analysis and fresh-<span class="hlt">water</span> testing; they provide a basis for understanding and predicting with confidence the performance of all components of an OC-OTEC system except the turbine. Seawater tests have confirmed the results that were obtained in fresh-<span class="hlt">water</span> tests and predicted by the analytical models of the components. A sound technical basis has been established for the design of larger systems in which net power will be produced for the first time from OC-OTEC technology. Design and operation of a complete OC-OTEC system that produces power will provide sufficient confidence to warrant complete transfer of OC-OTEC technology to the private sector. Each components performance is described in a separate chapter written by the principal investigator responsible for technical aspects of the specific tests. Chapters have been indexed separately for inclusion on the data base.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6193607','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6193607"><span>Results of scoping tests for <span class="hlt">open</span>-cycle OTEC (<span class="hlt">ocean</span> thermal energy conversion) components operating with seawater</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zangrando, F; Bharathan, D; Green, H J; Link, H F; Parsons, B K; Parsons, J M; Pesaran, A A; Panchal, C B</p> <p>1990-09-01</p> <p>This report presents comprehensive documentation of the experimental research conducted on <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC) components operating with seawater as a working fluid. The results of this research are presented in the context of previous analysis and fresh-<span class="hlt">water</span> testing; they provide a basis for understanding and predicting with confidence the performance of all components of an OC-OTEC system except the turbine. Seawater tests have confirmed the results that were obtained in fresh-<span class="hlt">water</span> tests and predicted by the analytical models of the components. A sound technical basis has been established for the design of larger systems in which net power will be produced for the first time from OC-OTEC technology. Design and operation of a complete OC-OTEC system that produces power will provide sufficient confidence to warrant complete transfer of OC-OTEC technology to the private sector. Each components performance is described in a separate chapter written by the principal investigator responsible for technical aspects of the specific tests. Chapters have been indexed separately for inclusion on the data base.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1814515Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1814515Y"><span>Observed microphysical changes in Arctic mixed-phase clouds when transitioning from sea-ice to <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Young, Gillian; Jones, Hazel M.; Crosier, Jonathan; Bower, Keith N.; Darbyshire, Eoghan; Taylor, Jonathan W.; Liu, Dantong; Allan, James D.; Williams, Paul I.; Gallagher, Martin W.; Choularton, Thomas W.</p> <p>2016-04-01</p> <p>The Arctic sea-ice is intricately coupled to the atmosphere[1]. The decreasing sea-ice extent with the changing climate raises questions about how Arctic cloud structure will respond. Any effort to answer these questions is hindered by the scarcity of atmospheric observations in this region. Comprehensive cloud and aerosol measurements could allow for an improved understanding of the relationship between surface conditions and cloud structure; knowledge which could be key in validating weather model forecasts. Previous studies[2] have shown via remote sensing that cloudiness increases over the marginal ice zone (MIZ) and <span class="hlt">ocean</span> with comparison to the sea-ice; however, to our knowledge, detailed in-situ data of this transition have not been previously presented. In 2013, the Aerosol-Cloud Coupling and Climate Interactions in the Arctic (ACCACIA) campaign was carried out in the vicinity of Svalbard, Norway to collect in-situ observations of the Arctic atmosphere and investigate this issue. Fitted with a suite of remote sensing, cloud and aerosol instrumentation, the FAAM BAe-146 aircraft was used during the spring segment of the campaign (Mar-Apr 2013). One case study (23rd Mar 2013) produced excellent coverage of the atmospheric changes when transitioning from sea-ice, through the MIZ, to the <span class="hlt">open</span> <span class="hlt">ocean</span>. Clear microphysical changes were observed, with the cloud liquid-<span class="hlt">water</span> content increasing by almost four times over the transition. Cloud base, depth and droplet number also increased, whilst ice number concentrations decreased slightly. The surface warmed by ~13 K from sea-ice to <span class="hlt">ocean</span>, with minor differences in aerosol particle number (of sizes corresponding to Cloud Condensation Nuclei or Ice Nucleating Particles) observed, suggesting that the primary driver of these microphysical changes was the increased heat fluxes and induced turbulence from the warm <span class="hlt">ocean</span> surface as expected. References: [1] Kapsch, M.L., Graversen, R.G. and Tjernström, M. Springtime</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=547478','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=547478"><span>Heat Sterilization of <span class="hlt">Water</span> in a Large <span class="hlt">Open</span> Vessel</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Yale, Charles E.; Linsley, James G.; Anderson, Lawrence C.</p> <p>1968-01-01</p> <p>A safe, convenient, and economical method of preparing and dispensing a large volume of sterile <span class="hlt">water</span> in a movable container is described. A caster-mounted, rectangular, 100-gal, stainless-steel <span class="hlt">water</span> tank was fabricated. An audible, solid-state <span class="hlt">water</span>-level alarm was developed for use with a detachable sensing probe that could be autoclaved. A filter system was constructed to allow the tank to be autoclaved as an <span class="hlt">open</span> vessel. Thermocouples were mounted within the tank of <span class="hlt">water</span> to study the time-temperature relationships of the <span class="hlt">water</span> during the sterilization cycle. In a downward displacement autoclave with a hot jacket, 75 min were required for the <span class="hlt">water</span> temperature to rise from 140 to 240 F (60 to 116 C). A total of 3 hr for heating and holding includes an adequate safety factor to insure the sterility of the <span class="hlt">water</span> immediately after autoclaving. The long-term sterility of the <span class="hlt">water</span> and the safety of the system were verified by using the <span class="hlt">water</span> to maintain a germ-free animal colony. Images Fig. 1 Fig. 2 PMID:5647520</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JAESc.135...35F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JAESc.135...35F"><span>Remnants of a Late Triassic <span class="hlt">ocean</span> island in the Gufeng area, northern Tibet: Implications for the <span class="hlt">opening</span> and early evolution of the Bangong-Nujiang Tethyan <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fan, Jian-Jun; Li, Cai; Wang, Ming; Liu, Yi-Ming; Xie, Chao-Ming</p> <p>2017-03-01</p> <p>In this paper we present new major and trace element compositions of basaltic rocks in the Gufeng <span class="hlt">ocean</span> island (GFOI) area in the western segment of the Bangong-Nujiang Suture Zone, northern Tibet. Our aim was to assess the genesis of these rocks and discuss the implications of this new dataset for the evolution of the Bangong-Nujiang Tethyan <span class="hlt">Ocean</span>. An <span class="hlt">ocean</span>-island-type double-layer structure comprising a basaltic basement and an <span class="hlt">oceanic</span> sedimentary cover sequence found within the GFOI provides direct evidence for the interpretation that the assemblage is a typical <span class="hlt">ocean</span> island. The basalts in the GFOI can be divided into three types (named G1, G2 and G3 basalts), and these basalts range in composition from MORB to OIB types, which is typical of <span class="hlt">ocean</span> islands. The G1 basalts have MORB-type affinities, possibly indicating the existence of MORB <span class="hlt">oceanic</span> crust under the GFOI. The G2 basalts represent the early stage of formation of the GFOI, and are produced by the interaction of rising OIB-type basaltic magma and the existing MORB <span class="hlt">oceanic</span> crust. The G3 basalts are typical OIB basalts and they are the products of the direct eruption of OIB-type basaltic magmas. The G3 basalts have high (La/Yb)N (12.3-14.4), (Ce/Yb)N (10.8-11.8), (La/Sm)N (2.39-2.76), and (Sm/Yb)N (4.89-5.23) ratios, indicating the presence of <span class="hlt">oceanic</span> lithosphere below the GFOI with a thickness of 50-60 km. Geochemical analyses of the GFOI cherts show that they contain terrigenous material, indicating the GFOI formed close to a continental margin. Norian conodont fossils within the GFOI limestones indicate the GFOI formed during the Late Triassic. These data, combined with geological evidence and a half-space model of lithosphere cooling, where the thickness of the <span class="hlt">oceanic</span> lithosphere is determined from the age of the lithosphere, indicate that the western segment of the Bangong-Nujiang Tethyan <span class="hlt">Ocean</span> <span class="hlt">opened</span> initially in the late Permian, expanded rapidly during the Early-Middle Triassic, and was a</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1989STIN...9020493.','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1989STIN...9020493."><span>Innovative turbine concepts for <span class="hlt">open</span>-cycle OTEC (<span class="hlt">Ocean</span> Thermal Energy Conversion)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p></p> <p>1989-12-01</p> <p>The results are summarized of preliminary studies conducted to identify and evaluate three innovative concepts for an <span class="hlt">open</span> cycle <span class="hlt">ocean</span> thermal energy conversion (OTEC) steam turbine that could significantly reduce the cost of OTEC electrical power plants. The three concepts are: (1) a crossflow turbine, (2) a vertical axis, axial flow turbine, and (3) a double flow, radial inflow turbine with mixed flow blading. In all cases, the innovation involves the use of lightweight, composite plastic blading and a physical geometry that facilitates efficient fluid flow to and from the other major system components and reduces the structural requirements for both the turbine or the system vacuum enclosure, or both. The performance, mechanical design, and cost of each of the concepts are developed to varying degrees but in sufficient detail to show that the potential exists for cost reductions to the goals established in the U.S. Department of Energy's planning documents. Specifically, results showed that an axial turbine operating with 33 percent higher steam throughput and 7 percent lower efficiency than the most efficient configuration provides the most cost effective <span class="hlt">open</span>-cycle OTEC system. The vacuum enclosure can be significantly modified to reduce costs by establishing better interfaces with the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/7109796','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/7109796"><span>Innovative turbine concepts for <span class="hlt">open</span>-cycle OTEC (<span class="hlt">ocean</span> thermal energy conversion)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Not Available</p> <p>1989-12-01</p> <p>This report summarizes the results of preliminary studies conducted to identify and evaluate three innovative concepts for an <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OTEC) steam turbine that could significantly reduce the cost of OTEC electrical power plants. The three concepts are (1) a crossflow turbine, (2) a vertical-axis, axial-flow turbine, and (3) a double-flow, radial-inflow turbine with mixed-flow blading. In all cases, the innovation involves the use of lightweight, composite plastic blading and a physical geometry that facilitates efficient fluid flow to and from the other major system components and reduces the structural requirements for both the turbine or the system vacuum enclosure, or both. The performance, mechanical design, and cost of each of the concepts are developed to varying degrees but in sufficient detail to show that the potential exists for cost reductions to the goals established in the US Department of Energy's planning documents. Specifically, results showed that an axial turbine operating with 33% higher steam throughput and 7% lower efficiency than the most efficient configuration provides the most cost-effective <span class="hlt">open</span>-cycle OTEC system. The vacuum enclosure can be significantly modified to reduce costs by establishing better interfaces with the system. 33 refs., 26 figs., 11 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1985STIN...8623043P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1985STIN...8623043P"><span>Thermodynamic systems analysis of <span class="hlt">open</span>-cycle <span class="hlt">Ocean</span> Thermal Energy Conversion (OTEC)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parsons, B. K.; Bharathan, D.; Althof, J. A.</p> <p>1985-09-01</p> <p>This report describes an updated thermal-hydraulic systems analysis program called OTECSYS that studies the integrated performance of an <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OTEC) plant, specifically, the effects of component performance, design parameters, and site specific resource data on the total system performance and plant size. OTECSYS can size the various <span class="hlt">open</span>-cycle power cycle and hydraulic components. Models for the evaporator, mist eliminator, turbine-generator diffuser, direct-contact condenser, exhaust compressors, seawater pumps, and seawater piping are included, as are evaluations of the pressure drops associated with the intercomponent connections. It can also determine the required steam, cold seawater, and warm seawater flow rates. OTECSYS uses an approach similar to earlier work and integrates the most up-to-date developments in component performance and configuration. The program format allows the user to examine subsystem concepts not currently included by creating new component models. It will be useful to the OTEC plant designer who wants to quantify the design point sizing, performance, and power production using site-specific resource data. Detailed design trade-offs are easily evaluated, and several examples of these types of investigations are presented using plant size and power as criteria.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015NatCC...5..877M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015NatCC...5..877M"><span>Decreasing intensity of <span class="hlt">open-ocean</span> convection in the Greenland and Iceland seas</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Moore, G. W. K.; Våge, K.; Pickart, R. S.; Renfrew, I. A.</p> <p>2015-09-01</p> <p>The air-sea transfer of heat and fresh <span class="hlt">water</span> plays a critical role in the global climate system. This is particularly true for the Greenland and Iceland seas, where these fluxes drive <span class="hlt">ocean</span> convection that contributes to Denmark Strait overflow <span class="hlt">water</span>, the densest component of the lower limb of the Atlantic Meridional Overturning Circulation (AMOC; ref. ). Here we show that the wintertime retreat of sea ice in the region, combined with different rates of warming for the atmosphere and sea surface of the Greenland and Iceland seas, has resulted in statistically significant reductions of approximately 20% in the magnitude of the winter air-sea heat fluxes since 1979. We also show that modes of climate variability other than the North Atlantic Oscillation (NAO; refs , , , , ) are required to fully characterize the regional air-sea interaction. Mixed-layer model simulations imply that further decreases in atmospheric forcing will exceed a threshold for the Greenland Sea whereby convection will become depth limited, reducing the ventilation of mid-depth <span class="hlt">waters</span> in the Nordic seas. In the Iceland Sea, further reductions have the potential to decrease the supply of the densest overflow <span class="hlt">waters</span> to the AMOC (ref. ).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1813993S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1813993S"><span>The influence of the distribution of sea-<span class="hlt">water</span> conductivity on the <span class="hlt">ocean</span> induced magnetic field</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Saynisch, Jan; Irrgang, Christopher; Hagedoorn, Jan; Thomas, Maik</p> <p>2016-04-01</p> <p>The variability of <span class="hlt">oceanic</span> contributions to Earth's magnetic field ranges from sub-daily scales to thousands of years. To study the sensitivity and the range of <span class="hlt">oceanic</span> magnetic signals, an induction model is coupled to an <span class="hlt">ocean</span> general circulation model. In the presented study, the sensitivity of the induction process to spatial and temporal variations in sea-<span class="hlt">water</span> conductivity is investigated. In current calculations of <span class="hlt">ocean</span> induced magnetic fields, a realistic distribution of sea-<span class="hlt">water</span> conductivity is often neglected. We shown that assuming an <span class="hlt">ocean</span>-wide constant conductivity is insufficient to accurately capture the spatial and, more important, the temporal variability of the magnetic signal. Using a realistic global sea-<span class="hlt">water</span> conductivity distribution changes the temporal variability of the magnetic field up to 45%. Vertical gradients in sea-<span class="hlt">water</span> conductivity prove to be a key factor for the variability of the <span class="hlt">oceanic</span> induced magnetic field.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24889419','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24889419"><span>Redox heterogeneity of subsurface <span class="hlt">waters</span> in the Mesoproterozoic <span class="hlt">ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sperling, E A; Rooney, A D; Hays, L; Sergeev, V N; Vorob'eva, N G; Sergeeva, N D; Selby, D; Johnston, D T; Knoll, A H</p> <p>2014-09-01</p> <p>A substantial body of evidence suggests that subsurface <span class="hlt">water</span> masses in mid-Proterozoic marine basins were commonly anoxic, either euxinic (sulfidic) or ferruginous (free ferrous iron). To further document redox variations during this interval, a multiproxy geochemical and paleobiological investigation was conducted on the approximately 1000-m-thick Mesoproterozoic (Lower Riphean) Arlan Member of the Kaltasy Formation, central Russia. Iron speciation geochemistry, supported by organic geochemistry, redox-sensitive trace element abundances, and pyrite sulfur isotope values, indicates that basinal calcareous shales of the Arlan Member were deposited beneath an oxygenated <span class="hlt">water</span> column, and consistent with this interpretation, eukaryotic microfossils are abundant in basinal facies. The Rhenium-Osmium (Re-Os) systematics of the Arlan shales yield depositional ages of 1414±40 and 1427±43 Ma for two horizons near the base of the succession, consistent with previously proposed correlations. The presence of free oxygen in a basinal environment adds an important end member to Proterozoic redox heterogeneity, requiring an explanation in light of previous data from time-equivalent basins. Very low total organic carbon contents in the Arlan Member are perhaps the key--oxic deep <span class="hlt">waters</span> are more likely (under any level of atmospheric O2) in oligotrophic systems with low export production. Documentation of a full range of redox heterogeneity in subsurface <span class="hlt">waters</span> and the existence of local redox controls indicate that no single stratigraphic section or basin can adequately capture both the mean redox profile of Proterozoic <span class="hlt">oceans</span> and its variance at any given point in time.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1815059B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1815059B"><span>Splitting of Atlantic <span class="hlt">water</span> transport towards the Arctic <span class="hlt">Ocean</span> into the Fram Strait and Barents Sea Branches - mechanisms and consequences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Beszczynska-Möller, Agnieszka; Skagseth, Øystein; von Appen, Wilken-Jon; Walczowski, Waldemar; Lien, Vidar</p> <p>2016-04-01</p> <p>The heat content in the Arctic <span class="hlt">Ocean</span> is to a large extent determined by <span class="hlt">oceanic</span> advection from the south. During the last two decades the extraordinary warm Atlantic <span class="hlt">water</span> (AW) inflow has been reported to progress through the Nordic Seas into the Arctic <span class="hlt">Ocean</span>. Warm anomalies can result from higher air temperatures (smaller heat loss) in the Nordic Seas, and/or from an increased <span class="hlt">oceanic</span> advection. But the ultimate fate of warm anomalies of Atlantic origin depends strongly on their two possible pathways towards the Arctic <span class="hlt">Ocean</span>. The AW temperature changes from 7-10°C at the entrance to the Nordic Seas, to 6-6.5°C in the Barents Sea <span class="hlt">opening</span> and 3-3.5°C as the AW leaving Fram Strait enters the Arctic <span class="hlt">Ocean</span>. When AW passes through the shallow Barents Sea, nearly all its heat is lost due to atmospheric cooling and AW looses its signature. In the deep Fram Strait the upper part of Atlantic <span class="hlt">water</span> becomes transformed into a less saline and colder surface layer and thus AW preserves its warm core. A significant warming and high variability of AW volume transport was observed in two recent decades in the West Spitsbergen Current, representing the Fram Strait Branch of Atlantic inflow. The AW inflow through Fram Strait carries between 26 and 50 TW of heat into the Arctic <span class="hlt">Ocean</span>. While the <span class="hlt">oceanic</span> heat influx to the Barents Sea is of a similar order, the heat leaving it through the northern exit into the Arctic <span class="hlt">Ocean</span> is negligible. The relative strength of two Atlantic <span class="hlt">water</span> branches through Fram Strait and the Barents Sea governs the <span class="hlt">oceanic</span> heat transport into the Arctic <span class="hlt">Ocean</span>. According to recently proposed mechanism, the Atlantic <span class="hlt">water</span> flow in the Barents Sea Branch is controlled by the strength of atmospheric low over the northern Barents Sea, acting through a wind-induced Ekman divergence, which intensifies eastward AW flow. The Atlantic <span class="hlt">water</span> transport in the Fram Strait Branch is mainly forced by the large-scale low-pressure system over the eastern Norwegian and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70030249','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70030249"><span>Shelf and <span class="hlt">open-ocean</span> calcareous phytoplankton assemblages across the Paleocene-Eocene thermal maximum: Implications for global productivity gradients</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Gibbs, S.J.; Bralower, T.J.; Bown, P.R.; Zachos, J.C.; Bybell, L.M.</p> <p>2006-01-01</p> <p>Abrupt global warming and profound perturbation of the carbon cycle during the Paleocene-Eocene Thermal Maximum (PETM, ca. 55 Ma) have been linked to a massive release of carbon into the <span class="hlt">ocean</span>-atmosphere system. Increased phytoplankton productivity has been invoked to cause subsequent CO2 drawdown, cooling, and environmental recovery. However, interpretations of geochemical and biotic data differ on when and where this increased productivity occurred. Here we present high-resolution nannofossil assemblage data from a shelf section (the U.S. Geological Survey [USGS] drill hole at Wilson Lake, New Jersey) and an <span class="hlt">open-ocean</span> location (<span class="hlt">Ocean</span> Drilling Program [ODP] Site 1209, paleoequatorial Pacific). These data combined with published biotic records indicate a transient steepening of shelf-offshelf trophic gradients across the PETM onset and peak, with a decrease in <span class="hlt">open-ocean</span> productivity coeval with increased nutrient availability in shelf areas. Productivity levels recovered in the <span class="hlt">open</span> <span class="hlt">ocean</span> during the later stages of the event, which, coupled with intensified continental weathering rates, may have played an important role in carbon sequestration and CO2 drawdown. ?? 2006 Geological Society of America.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991STIN...9212336R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991STIN...9212336R"><span>Production of desalinated <span class="hlt">water</span> using <span class="hlt">ocean</span> thermal energy</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rabas, T.; Panchal, C.</p> <p></p> <p>This paper describes an <span class="hlt">Ocean</span> Thermal Energy Conversion (OTEC) desalination plant that consists of a multistage flash evaporator (MSF), a closed-cycle OTEC power plant, and an appropriate seawater system depending if the desalination plant is land based or floating. OTEC desalination plants of this type are preferred because the production of desalinated <span class="hlt">water</span> far exceeds that obtained from other OTEC plant types employing the same size seawater system. The focus of the paper is on the multistage flash evaporator. The similarities and differences between conventional MSF and OTEC multistage flash evaporators (OTEC-MSF) are first described. Then the details of the OTEC-MSF evaporator design are discussed and preliminary correlations are recommended for the three major elements: the flash chamber, the moisture removal device, and the condenser. Recent advances such as enhanced condenser tubes, condensers of the compact type, and corrugated-plate moisture separators are introduced into the design. Comparisons of the <span class="hlt">water</span> production capability, evaporator shell volume, and material cost are then presented for state-of-the-art and the new design concepts.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5291410','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5291410"><span>Production of desalinated <span class="hlt">water</span> using <span class="hlt">ocean</span> thermal energy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Rabas, T.; Panchal, C.</p> <p>1991-01-01</p> <p>This paper describes an <span class="hlt">Ocean</span> Thermal Energy Conversion (OTEC) desalination plant that consists of a multistage flash evaporator (MSF), a closed-cycle OTEC power plant, and an appropriate seawater system depending if the desalination plant is land based or floating. OTEC desalination plants of this type are preferred because the production of desalinated <span class="hlt">water</span> far exceeds that obtained from other OTEC plant types employing the same size seawater system. The focus of the paper is on the multistage flash evaporator. The similarities and differences between conventional MSF and OTEC multistage flash evaporators (OTEC-MSF) are first described. Then the details of the OTEC-MSF evaporator design are discussed and preliminary correlations are recommended for the three major elements: the flash chamber, the moisture removal device, and the condenser. Recent advances such as enhanced condenser tubes, condensers of the compact type, and corrugated-plate moisture separators are introduced into the design. Comparisons of the <span class="hlt">water</span> production capability, evaporator shell volume, and material cost are then presented for state-of-the-art and the new design concepts. 20 refs., 11 figs., 5 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1910971T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1910971T"><span>Pathways of upwelling deep <span class="hlt">waters</span> to the surface of the Southern <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tamsitt, Veronica; Drake, Henri; Morrison, Adele; Talley, Lynne; Dufour, Carolina; Gray, Alison; Griffies, Stephen; Mazloff, Matthew; Sarmiento, Jorge; Wang, Jinbo; Weijer, Wilbert</p> <p>2017-04-01</p> <p>Upwelling of Atlantic, Indian and Pacific deep <span class="hlt">waters</span> to the sea surface in the Southern <span class="hlt">Ocean</span> closes the global overturning circulation and is fundamentally important for <span class="hlt">oceanic</span> uptake of anthropogenic carbon and heat, nutrient resupply for sustaining <span class="hlt">oceanic</span> biological production, and the melt rate of ice shelves. Here we go beyond the two-dimensional view of Southern <span class="hlt">Ocean</span> upwelling, to show detailed Southern <span class="hlt">Ocean</span> upwelling pathways in three dimensions, using hydrographic observations and particle tracking in high-resolution <span class="hlt">ocean</span> and climate models. The northern deep <span class="hlt">waters</span> enter the Antarctic Circumpolar Current (ACC) via narrow southward currents along the boundaries of the three <span class="hlt">ocean</span> basins, before spiraling southeastward and upward through the ACC. Upwelling is greatly enhanced at five major topographic features, associated with vigorous mesoscale eddy activity. Deep <span class="hlt">water</span> reaches the upper <span class="hlt">ocean</span> predominantly south of the southern ACC boundary, with a spatially nonuniform distribution, regionalizing warm <span class="hlt">water</span> supply to Antarctic ice shelves and the delivery of nutrient and carbon-rich <span class="hlt">water</span> to the sea surface. The timescale for half of the deep <span class="hlt">water</span> to upwell from 30°S to the mixed layer is on the order of 60-90 years, which has important implications for the timescale for signals to propagate through the deep <span class="hlt">ocean</span>. In addition, we quantify the diabatic transformation along particle trajectories, to identify where diabatic processes are important along the upwelling pathways.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.S13B2017G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.S13B2017G"><span>Modeling microseism generation off Southern California with a numerical wave model: Coastal wave reflection and <span class="hlt">open</span> <span class="hlt">ocean</span> interactions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Graham, N.; Clayton, R. W.; Kedar, S.; Webb, F.; Jones, C. E.</p> <p>2010-12-01</p> <p>Application of correlation methods to monitoring temporal variations for relatively short time windows can lead to a violation of the underlying assumption of the technique, that the sources are distributed randomly off either end of the station-station path. If this assumption is not met, the technique estimate can be biased by a favored projection of the Green’s function, which would lead to an incorrect travel time estimate and consequently an incorrect velocity estimate. Since monitoring temporal changes in geological structures of crustal scale is dominated by the <span class="hlt">ocean</span> microseismic band (~3-10 seconds), analysis of the microseisms source distribution is of particular interest. We present the first ever parameterizations of microseism generation by coastal reflection of <span class="hlt">ocean</span> gravity waves. The parameterizations have been implemented in a numerical wave model covering the <span class="hlt">waters</span> off Southern California. Using the theory of Longuet-Higgins [1950], we modeled the microseisms generation by computing the wave-wave interaction component of the swell with its coastal-reflected component, modified by a depth-dependent resonance term, along the Southern California Coast. Three simulations were conducted covering September 2007 to July 2009. In one simulation, no coastal reflection of wave energy was included, with simulated microseism generation only via “<span class="hlt">open</span> ocean” wave-wave interactions. Two other simulations tested simple parameterizations of coastal wave reflection based on a) specular, and b) scattered reflection from coastline segments. We compare the time-dependent microseisms amplitude to seismic observations throughout Southern California. We also compare the modeled source locations to those obtained by a location method based on accumulating the zero-lag correlations between data and synthetic surface waves generated at a mesh of potential source locations. Preliminary results show good agreement between model results and observations, and indicate</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/6719204','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/6719204"><span>Energy conversion method in the <span class="hlt">ocean</span> using the density difference of <span class="hlt">water</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Mochizuki, H.; Mitsuhashi, W.</p> <p>1981-01-01</p> <p>A new method which produces energy from the <span class="hlt">ocean</span> by utilizing the density difference of <span class="hlt">water</span>, by means of a ''chimney effect'', is proposed. Density difference of <span class="hlt">water</span> in the <span class="hlt">ocean</span> occurs in two ways, namely differences of consistency and <span class="hlt">water</span> temperature. For instance, fresh river <span class="hlt">water</span> and melting flows and icebergs are pointed out as some origins of the former, while thermal effects of volcanoes and hot springs may account for the latter. 5 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010ECSS...86..587S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010ECSS...86..587S"><span>Contrasting effects of managed <span class="hlt">opening</span> regimes on <span class="hlt">water</span> quality in two intermittently closed and <span class="hlt">open</span> coastal lakes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schallenberg, M.; Larned, S. T.; Hayward, S.; Arbuckle, C.</p> <p>2010-03-01</p> <p>Intermittently closed and <span class="hlt">open</span> lakes and lagoons (ICOLLs) are shallow barrier lakes which are intermittently connected to the sea and experience saline intrusions. Many ICOLLs are mechanically <span class="hlt">opened</span> to prevent flooding of surrounding agricultural and urban land and to flush <span class="hlt">water</span> of poor quality. In this study, the effects of modified <span class="hlt">opening</span> regimes (frequency and duration of barrier <span class="hlt">openings</span> and closures) on <span class="hlt">water</span> quality and phytoplankton in two New Zealand ICOLLs were investigated over a number of <span class="hlt">opening</span>/closure cycles. <span class="hlt">Water</span> quality in Lake Ellesmere (Te Waihora) responded weakly to both <span class="hlt">opening</span> and closing events, indicating that sea-ICOLL exchange did not markedly improve <span class="hlt">water</span> quality. Conversely, <span class="hlt">water</span> quality in Waituna Lagoon responded rapidly to barrier <span class="hlt">openings</span>; <span class="hlt">water</span> level decreased to near sea level within days of <span class="hlt">opening</span> and subsequent seawater exchange resulted in rapid decreases in nitrate and chlorophyll a concentrations. The closure of Waituna Lagoon resulted in rapid rise in <span class="hlt">water</span> level and a pulse of nitrate and phosphorus in the <span class="hlt">water</span> column and phytoplankton chlorophyll a concentrations increased with increasing closed-period duration. Based on data on the underwater light climate and nutrient dynamics, phytoplankton in Lake Ellesmere was probably light-limited, whereas phytoplankton in Waituna Lagoon was rarely light-limited, and appeared to be predominately P-limited. The marked differences in responses of Lake Ellesmere and Waituna Lagoon to barrier <span class="hlt">openings</span> and closures reflected differences in ICOLL <span class="hlt">water</span> levels and morphological characteristics, which dictated the degree of tidal flushing when the barriers were <span class="hlt">open</span>. The inter-ICOLL differences observed in this study indicate that unless the effects of ICOLL <span class="hlt">openings</span>/closures on phytoplankton and nutrient dynamics are understood, changes to ICOLL <span class="hlt">opening</span> regimes may have unintended consequences for the <span class="hlt">water</span> quality and ecology of these systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015Geote..49...75M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015Geote..49...75M"><span>Development of passive volcanic margins of the Central Atlantic and initial <span class="hlt">opening</span> of <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Melankholina, E. N.; Sushchevskaya, N. M.</p> <p>2015-01-01</p> <p>Geological and geophysical data on the Central Atlantic are discussed in order to elucidate the tectonic setting of the initial magmatic activity, rifting, and breakup resulting in the origination of Mesozoic <span class="hlt">ocean</span>. The structural, magmatic, and historical aspects of the problem are considered. It has been established that the initial dispersed rifting and low-capacity magmatism at proximal margins was followed by the migration of the process toward the central part of region with the formation of distal zones and the development of vigorous magmmatism, further breakup of the lithosphere and <span class="hlt">ocean</span> <span class="hlt">opening</span>. Magmatism, its sources, and the features of newly formed magmatic crust at both the rifting and breakup stages of margin development are discussed and compared with subsequent spreading magmatism. Sr, Nd, and Pb isotopic compositions show that the magmatic evolution of the Central Atlantic proximal margins bears the features of two enriched components, one of which is related to the EM-1 source, developing only at the North American margin. Another enriched component typical of the province as a whole is related to the EM-2 source. To a lesser extent, this component is expressed in igneous rocks of Guyana, which also bear the signature of the MORB-type depleted source typical of spreading tholeiites in the Atlantic <span class="hlt">Ocean</span>. Similar conditions are assumed for subsequent magmatism at the distal margins and for the early spreading basalts in the adjacent Atlantic belt, which also contain a small admixture of enriched material. A comparison of the magmatism at the margins of Central and North Atlantic reveals their specificity distinctly expressed in isotopic compositions of igneous rocks. In contrast to the typical region of the North Atlantic, the immediate melting of the enriched lithospheric source without the participation of plume-related melts is reconstructed for the proximal margins of the Central Atlantic. At the same time, decompression and melting in the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/122292','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/122292"><span>Risk assessment for produced <span class="hlt">water</span> discharges to Louisiana <span class="hlt">open</span> bays</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.</p> <p>1995-11-01</p> <p>Potential human health and environmental impacts from discharge of produced <span class="hlt">water</span> to the Gulf of Mexico concern regulators at the State and Federal levels, environmental interest groups, industry and the public. Current regulations in the United States require or propose azero discharge limit for coastal facilities based primarily on studies performed in low energy,poorly flushed environments. Produced <span class="hlt">water</span> discharges in coastal Louisiana, however,include a number located in <span class="hlt">open</span> bays, where potential and impacts are likely to be larger than the minimal impacts associated with offshore discharges, but smaller than those demonstrated in low-energy canal environments. This paper summarizes results of a conservative screening-level health and ecological assessment for contaminants discharged in produced <span class="hlt">water</span> to <span class="hlt">open</span> bays in Louisiana, and reports results of a probabilistic human health risk assessment for radium and lead. The initial human health and ecological risk assessments consisted of conservative screening analyses that identified potentially important contaminants and excluded others from further consideration. A more quantitative probabilistic risk assessment was completed for the human health effects of the two contaminants identified in this screen: radium and lead. This work is part of a series of studies on the health and ecological risks from discharges of produced <span class="hlt">water</span> to the Gulf of Mexico, supported by the United States Department of Energy (USDOE).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/ED299160.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/ED299160.pdf"><span>A Nation of <span class="hlt">Oceans</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Weber, Michael; Tinney, Richard</p> <p></p> <p>This book is for people that want to know more about the <span class="hlt">oceans</span>, its inhabitants, and the <span class="hlt">ocean</span> processes. The main text of the book describes individual marine ecosystems including offshore <span class="hlt">open</span> <span class="hlt">water</span>, benthic, nearshore tropical, nearshore temperate, and nearshore arctic ecosystems. Discussed are some of the basic ecological principles found…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://eric.ed.gov/?q=Arctic+AND+Ocean&id=ED299160','ERIC'); return false;" href="https://eric.ed.gov/?q=Arctic+AND+Ocean&id=ED299160"><span>A Nation of <span class="hlt">Oceans</span>.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Weber, Michael; Tinney, Richard</p> <p></p> <p>This book is for people that want to know more about the <span class="hlt">oceans</span>, its inhabitants, and the <span class="hlt">ocean</span> processes. The main text of the book describes individual marine ecosystems including offshore <span class="hlt">open</span> <span class="hlt">water</span>, benthic, nearshore tropical, nearshore temperate, and nearshore arctic ecosystems. Discussed are some of the basic ecological principles found…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFM.B22D..05Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFM.B22D..05Z"><span>Nitrogen Cycling In The Deep Subsurface Underlying Oligotrophic <span class="hlt">Open</span> <span class="hlt">Ocean</span> Regions: Metagenomic Analyses of North Pond Sediment Microbial Communities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ziebis, W.</p> <p>2016-12-01</p> <p>Recent research of the deep <span class="hlt">ocean</span> floor underlying <span class="hlt">open</span> <span class="hlt">ocean</span> regions in the Atlantic and Pacific has revealed that oxygen penetrates several tens of meters into the sediment column from the overlying <span class="hlt">water</span>. And, in contrast to the better-studied continental margin setting, nitrate also persists within these organic-poor sediments throughout the sediment column. Moreover, in places where seawater flows through the basaltic crust, it has been shown that oxygen diffuses upward into the overlying sediment, creating an oxic sediment layer above the basalt. The flanks of the Mid-Atlantic Ridge are characterized by sediment-filled depressions that are surrounded by a steep topography of basaltic outcrops, which are the conduits for low-temperature hydrothermally driven seawater circulation through the basaltic basement. IODP Expedition 336 targeted North Pond, one of such sediment ponds. 3 sites were drilled which varied in sediment thickness from about 90 m (U1382B, U1384A) to 40 m (U1383D/E). Oxygen penetrated deeply into the sediment column from the overlying <span class="hlt">water</span> (30 m) and diffused upward from the basaltic basement to several meters (10 - 20 m) above the basalt. Aerobic respiration created an anoxic zone in the middle of the sediment column. Concurrently, nitrate accumulated above bottom seawater concentrations to up to 50 µM. Previous investigations, using a stable isotope approach, showed an active subsurface nitrogen cycle. We obtained samples from all 3 drilling sites and selected 10 samples from the oxic upper layer, the upper suboxic transition zone, the anoxic middle, the lower suboxic zone and the deep oxic layer above the basalt for detailed analyses. We extracted intact cells from large volumes of sediment (1 L) using a density centrifugation approach for amplicon (16s rRNA) and metagenome sequencing, with the goal to characterize the phylogenetic and functional gene inventory in these different sediment layers. We will provide first results on the deep</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS53B..02V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS53B..02V"><span>Contemporary changes and links between salinity and the global <span class="hlt">ocean</span> <span class="hlt">water</span> cycle</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vinogradova, N. T.; Ponte, R. M.</p> <p>2016-12-01</p> <p>To understand the ongoing alteration of the Earth's <span class="hlt">water</span> budget, it is essential to assess the variability of its <span class="hlt">oceanic</span> constituent as this component supplies more than 75% of the evaporated and precipitated <span class="hlt">water</span> in the global <span class="hlt">water</span> cycle. Here we examine the change in the <span class="hlt">ocean</span> <span class="hlt">water</span> cycle and the <span class="hlt">ocean</span>'s response to such changes over the contemporary, well-observed period spanning the last two decades. In particular, we focus on recent changes in surface salinity and fluxes of freshwater within the atmosphere-<span class="hlt">ocean</span>-land-ice system. Using a combination of historical observations and data-constrained <span class="hlt">ocean</span> estimates we demonstrate that there have been persistent changes (defined as significant trends) in both salinity and the <span class="hlt">ocean</span> <span class="hlt">water</span> cycle in many <span class="hlt">ocean</span> regions, including the subtropical gyres in both hemispheres, low latitudes of the tropical Pacific, the North Atlantic subpolar gyre and the Arctic <span class="hlt">Ocean</span>. On average, the <span class="hlt">ocean</span> <span class="hlt">water</span> cycle has amplified by 5% since 1993, but strong regional variations exist, e.g., up to 11% intensification in the South Pacific contrasting with pattern weakening of -7% in the North Atlantic. An even larger spread in regional variations of the pattern amplification is visible in surface salinity records, ranging between +50% in the Southern <span class="hlt">Ocean</span> to -40% in the North Atlantic, averaging to less than 1% over the globe. These findings imply a time of emergence of anthropogenic hydrological signals shorter in surface freshwater fluxes than in surface salinity, and point to the importance of <span class="hlt">ocean</span> circulation and salt transports in shaping patterns of decadal change in surface salinity. The latter is discussed within a closed budget framework by examining the balance between the atmospheric freshwater fluxes and the <span class="hlt">ocean</span> salt fluxes in regions of salinity extremes, such as salinity maxima in the subtropical gyres and salinity minima in the tropics and high latitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15898670','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15898670"><span>Instrumenting free-swimming dolphins echolocating in <span class="hlt">open</span> <span class="hlt">water</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Martin, Stephen W; Phillips, Michael; Bauer, Eric J; Moore, Patrick W; Houser, Dorian S</p> <p>2005-04-01</p> <p>Dolphins within the Navy Marine Mammal Program use echolocation to effectively locate underwater mines. They currently outperform manmade systems at similar tasks, particularly in cluttered environments and on buried targets. In hopes of improving manmade mine-hunting sonar systems, two instrumentation packages were developed to monitor free-swimming dolphin motion and echolocation during <span class="hlt">open-water</span> target detection tasks. The biosonar measurement tool (BMT) is carried by a dolphin and monitors underwater position and attitude while simultaneously recording echolocation clicks and returning echoes through high-gain binaural receivers. The instrumented mine simulator (IMS) is a modified bottom target that monitors echolocation signals arriving at the target during ensonification. Dolphin subjects were trained to carry the BMT in <span class="hlt">open</span>-bay bottom-object target searches in which the IMS could serve as a bottom object. The instrumentation provides detailed data that reveal hereto-unavailable information on the search strategies of free-swimming dolphins conducting <span class="hlt">open-water</span>, bottom-object search tasks with echolocation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.H44D..01C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.H44D..01C"><span>Leveraging <span class="hlt">Open</span>-Source Software and Data Standards within the Integrated <span class="hlt">Water</span> Resources Science and Services Initiative</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Clark, E. P.</p> <p>2014-12-01</p> <p>The National <span class="hlt">Oceanic</span> and Atmospheric Administration together with the U.S. Army Corps of Engineers and the U.S. Geological Survey establish the Integrated <span class="hlt">Water</span> Resources Science and Service (IWRSS) consortium in 2011. IWRSS is a cross cutting, multidisciplinary approach to addressing complex <span class="hlt">water</span> problems. The IWRSS Interoperability and Data Synchronization Scoping Team was tasked with documenting requirements related to the sharing of data sets essential for monitoring, forecasting the <span class="hlt">water</span> nation's <span class="hlt">water</span> resources as well as informing operations and management of hydraulic structures. A number of <span class="hlt">open</span> source software tools were identified in the team's report as well as the need to adopt <span class="hlt">open</span> source data structures and standards. This presentation will discuss the potential applications of <span class="hlt">open</span>-source software and development practices within the IWRSS-Interoperability and Data Synchronization construct as well as explore the underlying benefits that <span class="hlt">open</span>-source approaches offer to the federal <span class="hlt">water</span> resources community. Programmatically this strategy facilitates a common operating picture between the federal <span class="hlt">water</span> enterprise that is essential for a weather and <span class="hlt">water</span> ready nation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990STIN...9111282B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990STIN...9111282B"><span>Conceptual design of an <span class="hlt">Open</span>-Cycle <span class="hlt">Ocean</span> Thermal Energy Conversion Net Power-Producing Experiment (OC-OTEC NPPE)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bharathan, D.; Green, H. J.; Link, H. F.; Parsons, B. K.; Parsons, J. M.; Zangrando, F.</p> <p>1990-07-01</p> <p>This report describes the conceptual design of an experiment to investigate heat and mass transfer and to assess the viability of <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC). The experiment will be developed in two stages, the Heat- and Mass-Transfer Experimental Apparatus (HMTEA) and the Net Power-Producing Experiment (NPPE). The goal for the HMTEA is to test heat exchangers. The goal for the NPPE is to experimentally verify OC-OTEC's feasibility by installing a turbine and testing the power-generating system. The design effort met the goals of both the HMTEA and the NPPE, and duplication of hardware was minimal. The choices made for the design resource <span class="hlt">water</span> flow rates are consistent with the availability of cold and warm seawater as a result of the seawater systems upgrade carried out by the U.S. Department of Energy (DOE), the state of Hawaii, and the Pacific International Center for High Technology Research. The choices regarding configuration of the system were made based on projected performance, degree of technical risk, schedule, and cost. The cost for the future phase of the design and the development of the HMTEA/NPPE is consistent with the projected future program funding levels. The HMTEA and NPPE were designed cooperatively by PICHTR, Argonne National Laboratory, and Solar Energy Research Institute under the guidance of DOE. The experiment will be located at the DOE's Seacoast Test Facility at the Natural Energy Laboratory of Hawaii, Kailua-Kona, Hawaii.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6625364','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6625364"><span>Conceptual design of an <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion net power-producing experiment (OC-OTEC NPPE)</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Bharathan, D.; Green, H.J.; Link, H.F.; Parsons, B.K.; Parsons, J.M.; Zangrando, F.</p> <p>1990-07-01</p> <p>This report describes the conceptual design of an experiment to investigate heat and mass transfer and to assess the viability of <span class="hlt">open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion (OC-OTEC). The experiment will be developed in two stages, the Heat- and Mass-Transfer Experimental Apparatus (HMTEA) and the Net Power-Producing Experiment (NPPE). The goal for the HMTEA is to test heat exchangers. The goal for the NPPE is to experimentally verify OC-OTEC's feasibility by installing a turbine and testing the power-generating system. The design effort met the goals of both the HMTEA and the NPPE, and duplication of hardware was minimal. The choices made for the design resource <span class="hlt">water</span> flow rates are consistent with the availability of cold and warm seawater as a result of the seawater systems upgrade carried out by the US Department of Energy (DOE), the state of Hawaii, and the Pacific International Center for High Technology Research. The choices regarding configuration of the system were made based on projected performance, degree of technical risk, schedule, and cost. The cost for the future phase of the design and the development of the HMTEA/NPPE is consistent with the projected future program funding levels. The HMTEA and NPPE were designed cooperatively by PICHTR, Argonne National Laboratory, and Solar Energy Research Institute under the guidance of DOE. The experiment will be located at the DOE's Seacoast Test Facility at the Natural Energy Laboratory of Hawaii, Kailua-Kona, Hawaii. 71 refs., 41 figs., 34 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMIN23D1749M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMIN23D1749M"><span>Collaboration using <span class="hlt">open</span> standards and <span class="hlt">open</span> source software (examples of DIAS/CEOS <span class="hlt">Water</span> Portal)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Miura, S.; Sekioka, S.; Kuroiwa, K.; Kudo, Y.</p> <p>2015-12-01</p> <p>The DIAS/CEOS <span class="hlt">Water</span> Portal is a part of the DIAS (Data Integration and Analysis System, http://www.editoria.u-tokyo.ac.jp/projects/dias/?locale=en_US) systems for data distribution for users including, but not limited to, scientists, decision makers and officers like river administrators. One of the functions of this portal is to enable one-stop search and access variable <span class="hlt">water</span> related data archived multiple data centers located all over the world. This portal itself does not store data. Instead, according to requests made by users on the web page, it retrieves data from distributed data centers on-the-fly and lets them download and see rendered images/plots. Our system mainly relies on the <span class="hlt">open</span> source software GI-cat (http://essi-lab.eu/do/view/GIcat) and <span class="hlt">open</span> standards such as OGC-CSW, Opensearch and OPeNDAP protocol to enable the above functions. Details on how it works will be introduced during the presentation. Although some data centers have unique meta data format and/or data search protocols, our portal's brokering function enables users to search across various data centers at one time. And this portal is also connected to other data brokering systems, including GEOSS DAB (Discovery and Access Broker). As a result, users can search over thousands of datasets, millions of files at one time. Users can access the DIAS/CEOS <span class="hlt">Water</span> Portal system at http://waterportal.ceos.org/.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/ds/0960','USGSPUBS'); return false;" href="https://pubs.usgs.gov/ds/0960"><span>Back-Island and <span class="hlt">Open-Ocean</span> Shorelines, and Sand Areas of the Undeveloped Areas of New Jersey Barrier Islands, March 9, 1991, to July 30, 2013</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Guy, Kristy K.</p> <p>2015-11-09</p> <p>This Data Series Report includes <span class="hlt">open-ocean</span> shorelines, back-island shorelines, back-island shoreline points, sand polygons, and sand lines for the undeveloped areas of New Jersey barrier islands. These data were extracted from orthoimagery (aerial photography) taken between March 9, 1991, and July 30, 2013. The images used were 0.3–1-meter (m)-resolution U.S. Geological Survey Digital Orthophoto Quarter Quads (DOQQ), U.S. Department of Agriculture National Agriculture Imagery Program (NAIP) images, National <span class="hlt">Oceanic</span> and Atmospheric Administration images, and New Jersey Geographic Information Network images. The back-island shorelines were hand-digitized at the intersects of the apparent back-island shoreline and transects spaced at 20-m intervals. The <span class="hlt">open-ocean</span> shorelines were hand-digitized at the approximate still-<span class="hlt">water</span> level, such as tide level, which was fit through the average position of waves and swash apparent on the beach. Hand-digitizing was done at a scale of approximately 1:2,000. The sand polygons were derived by an image-processing unsupervised classification technique that separates images into classes. The classes were then visually categorized as either sand or not sand. Sand lines were taken from the sand polygons. Also included in this report are 20-m-spaced transect lines and the transect base lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=336309&keyword=lake&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=336309&keyword=lake&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>Spatial and Temporal <span class="hlt">Water</span> Quality Patterns in <span class="hlt">Open-Water</span> Lake Michigan from the 2015 CSMI</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p><span class="hlt">Water</span> quality patterns in the Laurentian Great Lakes broadly reflect climate, surficial geography, and landuse but are also shaped by limnological and biological processes. <span class="hlt">Open-water</span> sampling conducted as part of the 2015 Lake Michigan interagency coordinated science and monito...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AcO....32..188G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AcO....32..188G"><span>Trends on the distribution of ciliates in the <span class="hlt">open</span> Pacific <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gómez, Fernando</p> <p>2007-09-01</p> <p>The distribution of planktonic ciliates, aloricate (naked) and loricate (tintinnid) was investigated in the <span class="hlt">open</span> <span class="hlt">waters</span> of the Oyashio and Kuroshio Currents, Philippine, Sulu, Celebes and South China Seas, and the western and central equatorial Pacific. The abundance of nauplii and post-naupliar copepods as potential predators was estimated. In average, the tintinnids represented 10-20% of the abundance of aloricate ciliates (50-200 cells L -1). One hundred and two species of 37 genera of tintinnids were recorded. As a general trend, the highest species richness was found in moderate oligotrophic <span class="hlt">waters</span>. Photographic records of some taxa of interest and unidentified specimens were reported. In the subarctic <span class="hlt">waters</span> of the Oyashio Current, a few tintinnid species showed high abundance fluctuations that may be controlled by the copepods. During the summer the species of Parafavella with longer loricae predominated in parallel to the increase of the copepodite abundance. In warm <span class="hlt">open</span> <span class="hlt">waters</span>, the success of a ciliate species could depend on its anti-grazing strategy. Eutintinnus apertus attached to a spine-bearing diatom was the most ubiquitous species. Tintinnids may be subjected to lower predation pressure than aloricate ciliates. The increase of the lorica length or the association with diatoms may be an anti-grazing strategy, which determines the success of one tintinnid taxon versus other congeneric species. Although the aloricate ciliates would be less affected than tintinnids by the reduction of food availability under oligotrophic conditions, the ciliate populations as a general trend seem to be controlled by the predators (top-down) rather than by the availability of food resources (bottom-up).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012BGD.....912845S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012BGD.....912845S"><span>Impact of <span class="hlt">open-ocean</span> convection on particle fluxes and sediment dynamics in the deep margin of the Gulf of Lions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stabholz, M.; Durrieu de Madron, X.; Canals, M.; Khripounoff, A.; Taupier-Letage, I.; Testor, P.; Heussner, S.; Kerhervé, P.; Delsaut, N.; Houpert, L.; Lastras, G.; Denneliou, B.</p> <p>2012-09-01</p> <p>The deep outer margin of the Gulf of Lions and the adjacent basin, in the Western Mediterranean Sea, are regularly impacted by <span class="hlt">open-ocean</span> convection, a major hydrodynamic event responsible for the ventilation of the deep <span class="hlt">water</span> in the Western Mediterranean Basin. However, the impact of <span class="hlt">open-ocean</span> convection on the flux and transport of particulate matter remains poorly understood. The variability of <span class="hlt">water</span> mass properties (i.e. temperature and salinity), currents, and particle fluxes was monitored between September 2007 and April 2009 at five instrumented mooring lines deployed between 2050 and 2350 m-depth in the deepest continental margin and adjacent basin. Four of the lines followed a NW-SE transect, while the fifth one was located on a sediment wave field to the west. The results of the main, central line SC2350 ("LION"), located at 42° 02.5' N and 4° 41' E, at 2350 m-depth, show that <span class="hlt">open-ocean</span> convection reached mid-<span class="hlt">water</span> depth (≈ 1000 m-depth) during winter 2007-2008, and reached the seabed (≈ 2350 m-depth) during winter 2008-2009. Horizontal currents were unusually strong with speeds up to 39 cm s-1 during winter 2008-2009. The measurements at all 5 different locations indicate that mid-depth and near-bottom currents and particle fluxes gave relatively consistent values of similar magnitude across the study area except during winter 2008-2009, when near-bottom fluxes abruptly increased by one to two orders of magnitude. Particulate organic carbon contents, which generally vary between 3 and 5%, were abnormally low (≤ 1%) during winter 2008-2009 and approached those observed in surface sediments (≈ 0.6%). Turbidity profiles made in the region demonstrated the existence of a bottom nepheloid layer, several hundred meters thick, and related to the resuspension of bottom sediments. These observations support the view that <span class="hlt">open-ocean</span> deep convection events in the Gulf of Lions can cause significant remobilization of sediments in the deep outer margin</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013BGeo...10.1097S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013BGeo...10.1097S"><span>Impact of <span class="hlt">open-ocean</span> convection on particle fluxes and sediment dynamics in the deep margin of the Gulf of Lions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stabholz, M.; Durrieu de Madron, X.; Canals, M.; Khripounoff, A.; Taupier-Letage, I.; Testor, P.; Heussner, S.; Kerhervé, P.; Delsaut, N.; Houpert, L.; Lastras, G.; Dennielou, B.</p> <p>2013-02-01</p> <p>The deep outer margin of the Gulf of Lions and the adjacent basin, in the western Mediterranean Sea, are regularly impacted by <span class="hlt">open-ocean</span> convection, a major hydrodynamic event responsible for the ventilation of the deep <span class="hlt">water</span> in the western Mediterranean Basin. However, the impact of <span class="hlt">open-ocean</span> convection on the flux and transport of particulate matter remains poorly understood. The variability of <span class="hlt">water</span> mass properties (i.e., temperature and salinity), currents, and particle fluxes were monitored between September 2007 and April 2009 at five instrumented mooring lines deployed between 2050 and 2350-m depth in the deepest continental margin and adjacent basin. Four of the lines followed a NW-SE transect, while the fifth one was located on a sediment wave field to the west. The results of the main, central line SC2350 ("LION") located at 42°02.5' N, 4°41' E, at 2350-m depth, show that <span class="hlt">open-ocean</span> convection reached mid-<span class="hlt">water</span> depth (≍ 1000-m depth) during winter 2007-2008, and reached the seabed (≍ 2350-m depth) during winter 2008-2009. Horizontal currents were unusually strong with speeds up to 39 cm s-1 during winter 2008-2009. The measurements at all 5 different locations indicate that mid-depth and near-bottom currents and particle fluxes gave relatively consistent values of similar magnitude across the study area except during winter 2008-2009, when near-bottom fluxes abruptly increased by one to two orders of magnitude. Particulate organic carbon contents, which generally vary between 3 and 5%, were abnormally low (≤ 1%) during winter 2008-2009 and approached those observed in surface sediments (≍ 0.6%). Turbidity profiles made in the region demonstrated the existence of a bottom nepheloid layer, several hundred meters thick, and related to the resuspension of bottom sediments. These observations support the view that <span class="hlt">open-ocean</span> deep convection events in the Gulf of Lions can cause significant remobilization of sediments in the deep outer margin and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=242413','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=242413"><span>Starvation-Survival Patterns of Sixteen Freshly Isolated <span class="hlt">Open-Ocean</span> Bacteria †</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Amy, Penny S.; Morita, Richard Y.</p> <p>1983-01-01</p> <p>Sixteen marine isolates from a NORPAX cruise, which were transferred once on medium after initial isolation, survived nutrient deprivation for at least 8 months (longest period test). All but one isolate remained cellularly intact, although their sizes and shapes changed greatly, and all became smaller, decreasing in size from 40 to 79%. Three starvation-survival patterns were demonstrated, namely (i) an initial increase in viable cells followed by a decrease until a constant number was reached, (ii) an increase in viable cells until a constant number was reached, and (iii) a decrease in viable cells until a constant number was reached. One isolate from each starvation-survival pattern was starved for 8 months and then was tested in comparison with 4-month-starved Ant-300 for [14C]glutamic acid uptake, respiration, and incorporation. The response to glutamic acid was rapid and linear in each case. The data indicate that the starvation-survival of Ant-300 is not an anomalous situation and that <span class="hlt">open</span> <span class="hlt">ocean</span> bacteria can withstand nutrient deprivation for long periods of time and still retain the capacity for active metabolism, if the nutrients become available. Images PMID:16346231</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/5426726','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/5426726"><span><span class="hlt">Open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion surface-condenser design analysis and computer program</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Panchal, C.B.; Rabas, T.J.</p> <p>1991-05-01</p> <p>This report documents a computer program for designing a surface condenser that condenses low-pressure steam in an <span class="hlt">ocean</span> thermal energy conversion (OTEC) power plant. The primary emphasis is on the <span class="hlt">open</span>-cycle (OC) OTEC power system, although the same condenser design can be used for conventional and hybrid cycles because of their highly similar operating conditions. In an OC-OTEC system, the pressure level is very low (deep vacuums), temperature differences are small, and the inlet noncondensable gas concentrations are high. Because current condenser designs, such as the shell-and-tube, are not adequate for such conditions, a plate-fin configuration is selected. This design can be implemented in aluminum, which makes it very cost-effective when compared with other state-of-the-art vacuum steam condenser designs. Support for selecting a plate-fin heat exchanger for OC-OTEC steam condensation can be found in the sizing (geometric details) and rating (heat transfer and pressure drop) calculations presented. These calculations are then used in a computer program to obtain all the necessary thermal performance details for developing design specifications for a plate-fin steam condenser. 20 refs., 5 figs., 5 tabs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1991STIN...9131709P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1991STIN...9131709P"><span><span class="hlt">Open</span>-cycle <span class="hlt">ocean</span> thermal energy conversion surface-condenser design analysis and computer program</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Panchal, C. B.; Rabas, T. J.</p> <p>1991-05-01</p> <p>This report documents a computer program for designing a surface condenser that condenses low-pressure steam in an <span class="hlt">ocean</span> thermal energy conversion (OTEC) power plant. The primary emphasis is on the <span class="hlt">open</span>-cycle (OC) OTEC power system, although the same condenser design can be used for conventional and hybrid cycles because of their highly similar operating conditions. In an OC-OTEC system, the pressure level is very low (deep vacuums), temperature differences are small, and the inlet noncondensable gas concentrations are high. Because current condenser designs, such as the shell-and-tube, are not adequate for such conditions, a plate-fin configuration is selected. This design can be implemented in aluminum, which makes it very cost-effective when compared with other state-of-the-art vacuum steam condenser designs. Support for selecting a plate-fin heat exchanger for OC-OTEC steam condensation can be found in the sizing (geometric details) and rating (heat transfer and pressure drop) calculations presented. These calculations are then used in a computer program to obtain all the necessary thermal performance details for developing design specifications for a plate-fin steam condenser.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19659552','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19659552"><span>Diversity of urea-degrading microorganisms in <span class="hlt">open-ocean</span> and estuarine planktonic communities.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Collier, Jackie L; Baker, Kristopher M; Bell, Sheryl L</p> <p>2009-12-01</p> <p>Urea is an important and dynamic natural component of marine nitrogen cycling and also a major contributor to anthropogenic eutrophication of coastal ecosystems, yet little is known about the identities or diversity of ureolytic marine microorganisms. Primers targeting the gene encoding urease were used to PCR-amplify, clone and sequence 709 urease gene fragments from 31 plankton samples collected at both estuarine and <span class="hlt">open-ocean</span> locations. Two hundred and eighty-six amplicons belonged to 22 distinct sequence types that were closely enough related to named organisms to be identified, and included urease sequences both from typical marine planktonic organisms and from bacteria usually associated with terrestrial habitats. The remaining 423 amplicons were not closely enough related to named organisms to be identified, and belonged to 96 distinct sequence types of which 43 types were found in two or more different samples. The distributions of unidentified urease sequence types suggested that some represented truly marine microorganisms while others reflected terrestrial inputs to low-salinity estuarine areas. The urease primers revealed this great diversity of ureolytic organisms because they were able to amplify many previously unknown, environmentally relevant urease genes, and they will support new approaches for exploring the role of urea in marine ecosystems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/87328','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/87328"><span>Risk assessment for produced <span class="hlt">water</span> discharges to Louisiana <span class="hlt">Open</span> Bays</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.</p> <p>1995-06-23</p> <p>Data were collected prior to termination of discharge at three sites (including two <span class="hlt">open</span> bay sites at Delacroix Island and Bay De Chene) for the risk assessments. The Delacroix Island Oil and Gas Field has been in production since the first well drilling in 1940; the Bay De Chene Field, since 1942. Concentrations of 226Ra, 228Ra, 210Po, and 228Th were measured in discharges. Radium conc. were measured in fish and shellfish tissues. Sediment PAH and metal conc. were also available. Benthos sampling was conducted. A survey of fishermen was conducted. The tiered risk assessment showed that human health risks from radium in produced <span class="hlt">water</span> appear to be small; ecological risk from radium and other radionuclides in produced <span class="hlt">water</span> also appear small. Many of the chemical contaminants discharged to <span class="hlt">open</span> Louisiana bays appear to present little human health or ecological risk. A conservative screening analysis suggested potential risks to human health from Hg and Pb and a potential risk to ecological receptors from total effluent, Sb, Cd, Cu, Pb, Ni, Ag, Zn, and phenol in the <span class="hlt">water</span> column and PAHs in sediment; quantitiative risk assessments are being done for these contaminants.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1987CSR.....7.1445M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1987CSR.....7.1445M"><span>Designing <span class="hlt">open</span> <span class="hlt">water</span> disposal for dredged muddy sediments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McAnally, William H.; Adamec, Stephen A.</p> <p>1987-11-01</p> <p><span class="hlt">Open</span> <span class="hlt">water</span> disposal of muddy sediments in the estuarine environment is practiced to minimize dredging costs and to preserve contained disposal site capacity. <span class="hlt">Open</span> <span class="hlt">water</span> sites are usually either dispersive or retentive. Dispersive sites are used in the expectation that disposed sediments will not remain there, but will be transported out of the site, leaving room for additional disposal. Retentive sites are designed to ensure that disposed sediments mostly remain within the site. Choice of one of these approaches depends on the site character, sediment character, and disposal quantities. Design of disposal management plans for both site types is accomplished by use of field observations, laboratory tests, and numerical modeling. Three disposal site studies illustrate the methods used. At the Alcatraz site in San Francisco Bay, a dispersive condition is maintained by use of constraints on dredged mud characteristics that were developed from laboratory tests on erosion rates and from numerical modeling of the dump process. Field experiments were designed to evaluate the management procedure. In Corpus Christi Bay a numerical model was used to determine how much disposed sediment returns to the navigation channel, and to devise a location for disposal that will minimize that return. In Puget Sound a model has been used to ensure that most of the disposed material remains in the site. New techniques, including a piped disposal through 60 m of <span class="hlt">water</span>, were investigated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.8567D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.8567D"><span>Autonomous hydrophone array for long-term acoustic monitoring in the <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>D'Eu, J.-F.; Brachet, C.; Goslin, J.; Royer, J.-Y.; Ammann, J.</p> <p>2009-04-01</p> <p>-term corrosion resistance. As neither the occurrence of seismic events, nor the recurrence period between events can be predicted, long-lasting deployments (one to several years) are required. The autonomy of the instruments now allows a turn-over period of up to 2 years. However to retrieve the data at shorter time intervals and to limit the turn-over ship-time costs, we are working on a new generation of disposable instruments with a 5-year autonomy and recoverable messengers containing the data, that could take advantage of ship's opportunities. In <span class="hlt">open</span> seas and remote areas (e.g. Southern <span class="hlt">Ocean</span>), this approach may provide a more accessible and cheaper alternative than observatories cabled to shore. Solutions based on real-time acoustic links between the hydrophones and an autonomous buoy remotely linked to shore also suffer from limited data-transfer rate, high consumption of power and vulnerability to sea conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25238388','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25238388"><span>Soliton turbulence in shallow <span class="hlt">water</span> <span class="hlt">ocean</span> surface waves.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Costa, Andrea; Osborne, Alfred R; Resio, Donald T; Alessio, Silvia; Chrivì, Elisabetta; Saggese, Enrica; Bellomo, Katinka; Long, Chuck E</p> <p>2014-09-05</p> <p>We analyze shallow <span class="hlt">water</span> wind waves in Currituck Sound, North Carolina and experimentally confirm, for the first time, the presence of soliton turbulence in <span class="hlt">ocean</span> waves. Soliton turbulence is an exotic form of nonlinear wave motion where low frequency energy may also be viewed as a dense soliton gas, described theoretically by the soliton limit of the Korteweg-deVries equation, a completely integrable soliton system: Hence the phrase "soliton turbulence" is synonymous with "integrable soliton turbulence." For periodic-quasiperiodic boundary conditions the ergodic solutions of Korteweg-deVries are exactly solvable by finite gap theory (FGT), the basis of our data analysis. We find that large amplitude measured wave trains near the energetic peak of a storm have low frequency power spectra that behave as ∼ω-1. We use the linear Fourier transform to estimate this power law from the power spectrum and to filter densely packed soliton wave trains from the data. We apply FGT to determine the soliton spectrum and find that the low frequency ∼ω-1 region is soliton dominated. The solitons have random FGT phases, a soliton random phase approximation, which supports our interpretation of the data as soliton turbulence. From the probability density of the solitons we are able to demonstrate that the solitons are dense in time and highly non-Gaussian.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.3398B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.3398B"><span>The Toarcian <span class="hlt">Oceanic</span> Anoxic Event: a shallow-<span class="hlt">water</span> perspective</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bodin, Stephane; Krencker, Francois-Nicolas; Kabiri, Lahcen; Immenhauser, Adrian</p> <p>2015-04-01</p> <p>The Toarcian <span class="hlt">ocean</span> anoxic event (T-OAE, ca. 183 Ma) corresponds to a major perturbation of the carbon cycle as reflected by a marked decrease (2 to 7 per mil) in carbon-isotope ratios of various carbonate and organic matter phases. Severe environmental perturbations and biotic turnovers are accompanying the unfolding of the T-OAE, which is thought to be initiated by the activity of the Karoo-Ferrar large igneous province. Most of the studies dedicated to the T-OAE were however undertaken in mud-rich, deep-<span class="hlt">water</span> setting, leaving vast uncertainties about its shallow-<span class="hlt">water</span> expression and accompanying sea-level fluctuations. Here we present an extensive sedimentological dataset of the shallow-<span class="hlt">water</span> record of the T-OAE within the Central High Atlas Basin of Morocco. The combination of ammonite and brachiopod biostratigraphy, together with carbon-isotope chemostratigraphy (on both carbonate and organic matter) allows a precise location of the T-OAE in the studied shallow-<span class="hlt">water</span> sections. Thanks to well-exposed and thick successions, relative sea-level variations were reconstructed on a high-resolution scale, highlighting several important facts. Firstly, the T-OAE interval is preceded by a 50 meters-deep incised valley, observed within the uppermost Polymorphum ammonite zone. Similar observations have been reported from Euro-boreal basins and, together with published evidences of coeval occurrence of relatively cool seawater temperature and low atmospheric pCO2, we postulate that this forced regression is driven by glacio-eustasy. This points at the occurrence of a "cold snap" event just prior to the onset of the T-OAE. Secondly, the inception of the T-OAE is marked by the demise of the Lithiotid-dominated neritic carbonate factory, replaced by siliciclastic-dominated sedimentation during the T-OAE negative carbon isotope shift. Thirdly, an important progradation of oo-biodetritic shoal occurs during the negative carbon isotope plateau, underlying that the renewal of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2008PhDT........55Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2008PhDT........55Y"><span><span class="hlt">Water</span> mass formation and circulation in the Persian Gulf and <span class="hlt">water</span> exchange with the Indian <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yao, Fengchao</p> <p></p> <p>The Persian Gulf is a shallow, semi-enclosed marginal sea where the Persian Gulf <span class="hlt">Water</span> (PGW), one of the most saline <span class="hlt">water</span> masses in the world, is formed due to the arid climate. The PGW flushes out of the Persian Gulf as a deep outflow and induces a surface inflow of the Indian <span class="hlt">Ocean</span> Surface <span class="hlt">Water</span> (IOSW), driving an inverse-estuarine type <span class="hlt">water</span> exchange through the Strait of Hormuz. In this dissertation, the circulation and <span class="hlt">water</span> mass transformation processes in the Persian Gulf and the <span class="hlt">water</span> exchange with the Indian <span class="hlt">Ocean</span> through the Strait of Hormuz, in response to the atmospheric forcing, are studied using the HYbrid Coordinate <span class="hlt">Ocean</span> Model (HYCOM). The model is driven by surface wind stress, heat and fresh <span class="hlt">water</span> fluxes derived from two sources: the COADS (Comprehensive <span class="hlt">Ocean</span>-Atmosphere Data Set) monthly climatology and high frequency (2-hourly) MM5 (The Fifth-Generation NCAR/Penn State Mesoscale Model) output. This study is motivated by the time series measurements in the Strait during December 1996 to March 1998 by Johns et al. (2003), which also serve as a major benchmark for evaluating the model results. The simulations with climatological forcing show that the IOSW propagates in two branches into the Gulf, one along the Iranian coast toward the northern gulf and the other one onto the southern banks driven by the Ekman drift by the prevailing northwesterly winds. These two branches of inflow form two cyclonic gyres in the northern and in the southern gulf respectively. Cold, saline deep <span class="hlt">waters</span> are formed both in the northern gulf and in the southern gulf during the wintertime cooling period and their exports contribute seasonally to the outflow in the strait. After formation in winter, the dense <span class="hlt">water</span> in the shallow southwestern gulf spills off into the strait and causes high-salinity pulses in the outflow in the strait, a phenomenon also present in the observations. The export of dense <span class="hlt">waters</span> from the northern gulf persists throughout the year, with the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRD..11810225B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRD..11810225B"><span>The nocturnal <span class="hlt">water</span> cycle in an <span class="hlt">open</span>-canopy forest</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Berkelhammer, M.; Hu, J.; Bailey, A.; Noone, D. C.; Still, C. J.; Barnard, H.; Gochis, D.; Hsiao, G. S.; Rahn, T.; Turnipseed, A.</p> <p>2013-09-01</p> <p>The movement of moisture into, out-of, and within forest ecosystems is modulated by feedbacks that stem from processes which couple plants, soil, and the atmosphere. While an understanding of these processes has been gleaned from Eddy Covariance techniques, the reliability of the method suffers at night because of weak turbulence. During the summer of 2011, continuous profiles of the isotopic composition (i.e., δ18O and δD) of <span class="hlt">water</span> vapor and periodic measurements of soil, leaf, and precipitation pools were measured in an <span class="hlt">open</span>-canopy ponderosa pine forest in central Colorado to study within-canopy nocturnal <span class="hlt">water</span> cycling. The isotopic composition of the nocturnal <span class="hlt">water</span> vapor varies significantly based on the relative contributions of the three major hydrological processes acting on the forest: dewfall, exchange of moisture between leaf <span class="hlt">waters</span> and canopy vapor, and periodic mixing between the canopy and background air. Dewfall proved to be surprisingly common (˜30% of the nights) and detectable on both the surface and within the canopy through the isotopic measurements. While surface dew could be observed using leaf wetness and soil moisture sensors, dew in the foliage was only measurable through isotopic analysis of the vapor and often occurred even when no dew accumulated on the surface. Nocturnal moisture cycling plays a critical role in <span class="hlt">water</span> availability in forest ecosystems through foliar absorption and transpiration, and assessing these dynamics, as done here, is necessary for fully characterizing the hydrological controls on terrestrial productivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140017103','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140017103"><span>SWIM: A Semi-Analytical <span class="hlt">Ocean</span> Color Inversion Algorithm for Optically Shallow <span class="hlt">Waters</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>McKinna, Lachlan I. W.; Werdell, P. Jeremy; Fearns, Peter R. C. S.; Weeks, Scarla J.; Reichstetter, Martina; Franz, Bryan A.; Shea, Donald M.; Feldman, Gene C.</p> <p>2014-01-01</p> <p><span class="hlt">Ocean</span> color remote sensing provides synoptic-scale, near-daily observations of marine inherent optical properties (IOPs). Whilst contemporary <span class="hlt">ocean</span> color algorithms are known to perform well in deep <span class="hlt">oceanic</span> <span class="hlt">waters</span>, they have difficulty operating in optically clear, shallow marine environments where light reflected from the seafloor contributes to the <span class="hlt">water</span>-leaving radiance. The effect of benthic reflectance in optically shallow <span class="hlt">waters</span> is known to adversely affect algorithms developed for optically deep <span class="hlt">waters</span> [1, 2]. Whilst adapted versions of optically deep <span class="hlt">ocean</span> color algorithms have been applied to optically shallow regions with reasonable success [3], there is presently no approach that directly corrects for bottom reflectance using existing knowledge of bathymetry and benthic albedo.To address the issue of optically shallow <span class="hlt">waters</span>, we have developed a semi-analytical <span class="hlt">ocean</span> color inversion algorithm: the Shallow <span class="hlt">Water</span> Inversion Model (SWIM). SWIM uses existing bathymetry and a derived benthic albedo map to correct for bottom reflectance using the semi-analytical model of Lee et al [4]. The algorithm was incorporated into the NASA <span class="hlt">Ocean</span> Biology Processing Groups L2GEN program and tested in optically shallow <span class="hlt">waters</span> of the Great Barrier Reef, Australia. In-lieu of readily available in situ matchup data, we present a comparison between SWIM and two contemporary <span class="hlt">ocean</span> color algorithms, the Generalized Inherent Optical Property Algorithm (GIOP) and the Quasi-Analytical Algorithm (QAA).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9535E..1ID','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9535E..1ID"><span>Estimating chlorophyll concentrations in the optically complex <span class="hlt">waters</span> of the North Aegean Sea from field and satellite <span class="hlt">ocean</span> colour measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Drakopoulos, P. G.; Banks, A. C.; Kakagiannis, G.; Karageorgis, A. P.; Lagaria, A.; Papadopoulou, A.; Psarra, S.; Spyridakis, N.; Zervakis, V.</p> <p>2015-06-01</p> <p>In the Aegean Sea and Eastern Mediterranean there are large discrepancies between in situ and satellite <span class="hlt">ocean</span> colour derived chlorophyll concentrations. The quantity that is monitored by <span class="hlt">ocean</span> colour satellites and that can be used in the estimation of chlorophyll concentration is the remote sensing reflectance, defined as the ratio of the <span class="hlt">water</span> leaving spectral radiance to the downwelling spectral irradiance. It can be determined in the field, with either above or in-<span class="hlt">water</span> radiance and irradiance measurements. The complex optical properties of the North-East Aegean Sea, including radiance and irradiance, were studied during the AegeanMarTech project. Chlorophyll concentration estimates were derived from simultaneous above and in-<span class="hlt">water</span> radiometric measurements. These were validated against chlorophyll concentration field data and compared against concurrent MODIS data from which chlorophyll was derived using two simple empirical algorithms. It was found that the MedOC3 algorithm outperforms the operational OC3M-547 algorithm and produces the least bias when compared against HPLC derived in situ chlorophyll. It is concluded that the greatest uncertainty in the inversion arises due to CDOM absorption below the 488 nm band. The reflectance ratios indicated that there is always an excess of yellow matter present in the study area and the <span class="hlt">water</span> type could not be characterized optically as `'typical <span class="hlt">open</span> <span class="hlt">ocean</span>" Case 1.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017Ocgy...57..298K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017Ocgy...57..298K"><span>Distribution of deep-<span class="hlt">water</span> Scleractinian corals in the Atlantic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Keller, N. B.; Oskina, N. S.; Savilova, T. A.</p> <p>2017-03-01</p> <p>The distribution pattern of deep-<span class="hlt">water</span> Scleractinian corals was studied in the Atlantic <span class="hlt">Ocean</span> at a depth more than 2 km on the basis of our own and published data. It was shown that deep-<span class="hlt">water</span> corals predominate (with respect to species diversity and number) in the eastern part of the <span class="hlt">ocean</span>. In its western part, some species ( Desmophyllum dianthus, Flabellum angulare, etc.) were not revealed. In the tropical zone of the North Atlantic, the distribution pattern of shallow- and deep-<span class="hlt">water</span> corals differs. At the coast of South America, deepwater corals are absent, which is probably related to the deep part of the global <span class="hlt">oceanic</span> conveyor belt.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ERL....11b4007H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ERL....11b4007H"><span>Iron fertilisation and century-scale effects of <span class="hlt">open</span> <span class="hlt">ocean</span> dissolution of olivine in a simulated CO2 removal experiment</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hauck, Judith; Köhler, Peter; Wolf-Gladrow, Dieter; Völker, Christoph</p> <p>2016-02-01</p> <p>Carbon dioxide removal (CDR) approaches are efforts to reduce the atmospheric CO2 concentration. Here we use a marine carbon cycle model to investigate the effects of one CDR technique: the <span class="hlt">open</span> <span class="hlt">ocean</span> dissolution of the iron-containing mineral olivine. We analyse the maximum CDR potential of an annual dissolution of 3 Pg olivine during the 21st century and focus on the role of the micro-nutrient iron for the biological carbon pump. Distributing the products of olivine dissolution (bicarbonate, silicic acid, iron) uniformly in the global surface <span class="hlt">ocean</span> has a maximum CDR potential of 0.57 gC/g-olivine mainly due to the alkalinisation of the <span class="hlt">ocean</span>, with a significant contribution from the fertilisation of phytoplankton with silicic acid and iron. The part of the CDR caused by <span class="hlt">ocean</span> fertilisation is not permanent, while the CO2 sequestered by alkalinisation would be stored in the <span class="hlt">ocean</span> as long as alkalinity is not removed from the system. For high CO2 emission scenarios the CDR potential due to the alkalinity input becomes more efficient over time with increasing <span class="hlt">ocean</span> acidification. The alkalinity-induced CDR potential scales linearly with the amount of olivine, while the iron-induced CDR saturates at 113 PgC per century (on average ˜ 1.1 PgC yr-1) for an iron input rate of 2.3 Tg Fe yr-1 (1% of the iron contained in 3 Pg olivine). The additional iron-related CO2 uptake occurs in the Southern <span class="hlt">Ocean</span> and in the iron-limited regions of the Pacific. Effects of this approach on surface <span class="hlt">ocean</span> pH are small (\\lt 0.01).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22332507C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22332507C"><span><span class="hlt">Water</span> Cycling Between <span class="hlt">Ocean</span> and Mantle: Super-Earths Need Not be Waterworlds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cowan, Nicolas B.; Abbot, D. S.</p> <p>2014-01-01</p> <p>Large terrestrial planets are expected to have muted topography and deep <span class="hlt">oceans</span>, implying they should be entirely covered in <span class="hlt">water</span>, so-called waterworlds. Quantitatively, a planet ten times the mass of Earth is not expected to have exposed continents unless it has a <span class="hlt">water</span> mass fraction less than 3×10-5, roughly ten times drier than Earth. This is important because waterworlds lack a silicate weathering thermostat so their climate is predicted to be less stable than that of planets with exposed continents. <span class="hlt">Water</span> is partitioned, however, between a surface reservoir, the <span class="hlt">ocean</span>, and an interior reservoir, the mantle. Plate tectonics transports <span class="hlt">water</span> between these reservoirs on geological timescales. Degassing of melt at mid-<span class="hlt">ocean</span> ridges and serpentinization of <span class="hlt">oceanic</span> crust are mediated by sea-floor pressure, providing a stabilizing feedback on long-term <span class="hlt">ocean</span> volume. Motivated by Earth's approximately steady-state deep <span class="hlt">water</span> cycle, we develop a two-box model of the hydrosphere and derive steady-state solutions to the <span class="hlt">water</span>-partitioning on terrestrial planets. Since hydrostatic pressure is proportional to gravity, super-Earths with a deep <span class="hlt">water</span> cycle will tend to store most of their <span class="hlt">water</span> in the mantle. We conclude that tectonically active terrestrial planets with H2O mass fractions less than 3×10-3 will have both <span class="hlt">oceans</span> and exposed continents. The circumstellar habitable zone is therefore equally wide for any tectonically active planet.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013BGD....10.7879M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013BGD....10.7879M"><span><span class="hlt">Ocean</span> acidification state in western Antarctic surface <span class="hlt">waters</span>: drivers and interannual variability</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mattsdotter Björk, M.; Fransson, A.; Chierici, M.</p> <p>2013-05-01</p> <p>Each December during four years from 2006 to 2010, the surface <span class="hlt">water</span> carbonate system was measured and investigated in the Amundsen Sea and Ross Sea, western Antarctica as part of the Oden Southern <span class="hlt">Ocean</span> expeditions (OSO). The I/B Oden started in Punta Arenas in Chile and sailed southwest, passing through different regimes such as, the marginal/seasonal ice zone, fronts, coastal shelves, and polynyas. Discrete surface <span class="hlt">water</span> was sampled underway for analysis of total alkalinity (AT), total dissolved inorganic carbon (CT) and pH. Two of these parameters were used together with sea-surface temperature (SST), and salinity to obtain a full description of the surface <span class="hlt">water</span> carbonate system, including pH in situ and calcium carbonate saturation state of aragonite (ΩAr) and calcite (ΩCa). Multivariate analysis was used to investigate interannual variability and the major controls (sea-ice concentration, SST, salinity and chlorophyll a) on the variability in the carbonate system and Ω. This analysis showed that SST and chlorophyll a were the major drivers of the Ω variability in both the Amundsen and Ross seas. In 2007, the sea-ice edge was located further south and the area of the <span class="hlt">open</span> polynya was relatively small compared to 2010. We found the lowest pH in situ (7.932) and Ω = 1 values in the sea-ice zone and in the coastal Amundsen Sea, nearby marine out flowing glaciers. In 2010, the sea-ice coverage was the largest and the areas of the <span class="hlt">open</span> polynyas were the largest for the whole period. This year we found the lowest salinity and AT, coinciding with highest chl a. This implies that the highest ΩAr in 2010 was likely an effect of biological CO2 drawdown, which out-competed the dilution of carbonate ion concentration due to large melt <span class="hlt">water</span> volumes. We predict and discuss future Ω values, using our data and reported rates of <span class="hlt">oceanic</span> uptake of anthropogenic CO2, suggesting that the Amundsen Sea will become undersaturated with regard to aragonite about 20 yr sooner</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009GeoJI.177.1315T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009GeoJI.177.1315T"><span>A new scheme for the <span class="hlt">opening</span> of the South Atlantic <span class="hlt">Ocean</span> and the dissection of an Aptian salt basin</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Torsvik, Trond H.; Rousse, Sonia; Labails, Cinthia; Smethurst, Mark A.</p> <p>2009-06-01</p> <p>We present a revised model for the <span class="hlt">opening</span> of the South Atlantic <span class="hlt">Ocean</span> founded on a remapping of the continent-<span class="hlt">ocean</span> boundaries and Aptian salt basins, the chronology of magmatic activity in and around the <span class="hlt">ocean</span> basin and on the timing and character of associated intraplate deformation in Africa and South America. The new plate tectonic model is internally consistent and consistent with globally balanced plate motion solutions. The model includes realistic scenarios for intraplate deformation, pre-drift extension and seafloor spreading. Within the model, Aptian salt basins preserved in the South American (Brazilian) and African (Angola, Congo, Gabon) continental shelves are reunited in their original positions as parts of a single syn-rift basin in near subtropical latitudes (10°S-27°S). The basin was dissected at around 112 Ma (Aptian-Albian boundary) when the model suggests that seafloor spreading commenced north of the Walvis Ridge-Rio Grande Rise.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..1912071M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..1912071M"><span>Atlantic <span class="hlt">Water</span> variability in the 20th century Arctic <span class="hlt">Ocean</span> from observations, climatology and a global <span class="hlt">ocean</span> model.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Muilwijk, Morven; Ilicak, Mehmet; Smedsrud, Lars Henrik; Drange, Helge</p> <p>2017-04-01</p> <p>Warm and salty Atlantic <span class="hlt">Water</span> enters the Arctic <span class="hlt">Ocean</span> through the Fram Strait and the Western Barents Sea. The Atlantic <span class="hlt">Water</span> has a direct impact on the sea ice cover in regions north of Svalbard. Both historical observations and outcome from a fully coupled earth system model show a warming trend in core temperature of this Atlantic <span class="hlt">Water</span> inflow over the last few decades (1977-2015). For example, the upper 50-200m of the West Spitsbergen Current shows an observed overall warming of 1.1 ͦC since 1977. A portion of this recent large warming has been attributed to current global warming and possibly anthropogenic activity. However, low frequency oscillations (50-80 year time-scale) in Atlantic <span class="hlt">Water</span> temperature have been documented. Over the twentieth century, the Atlantic <span class="hlt">Water</span> temperature records from observations show two warm periods, in the 1930s-40s and in recent decades, and two colder periods, early in the 1900s and in the 1960s-70s. For example, north of Svalbard the Atlantic <span class="hlt">Water</span> was as warm as in 2015, during the Nautilus expedition in 1931. We believe that the Atlantic <span class="hlt">Water</span> warming trend in the Arctic <span class="hlt">Ocean</span> may be part of long-term multidecadal variability, which is influenced and reinforced by strong anthropogenic forcing. In this work we investigate this long term variability and discuss its relative contribution to the recent warming trend by using a global <span class="hlt">ocean</span> model. Simulations for the period 1871-2009 with the <span class="hlt">ocean</span>-sea ice component of the Norwegian Earth System Model (NorESM-O) were forced by a Twentieth Century Reanalysis data set. Atlantic <span class="hlt">Water</span> characteristics in these simulations are compared to available observations in a region north of Svalbard. Amongst these observations are hydrography measurements obtained during the Norwegian Young Sea Ice Cruise (N-ICE2015). Atlantic <span class="hlt">Water</span> pathways in the Arctic <span class="hlt">Ocean</span> for the period from 1871 to 2009 will also be presented as part of this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.H41L..06P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.H41L..06P"><span>Using Passive Microwaves for <span class="hlt">Open</span> <span class="hlt">Water</span> Monitoring and Flood Forecasting</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Parinussa, R.; Johnson, F.; Sharma, A.; Lakshmi, V.</p> <p>2015-12-01</p> <p>One of the biggest and severest natural disasters that society faces is floods. An important component that can help in reducing the impact of floods is satellite remote sensing as it allows for consistent monitoring and obtaining catchment information in absence of physical contact. Nowadays, passive microwave remote sensing observations are available in near real time (NRT) with a couple of hours delay from the actual sensing. The Advanced Microwave Scanning Radiometer 2 (AMSR2) is a multi-frequency passive microwave sensor onboard the Global Change Observation Mission 1 - <span class="hlt">Water</span> that was launched in May 2012. Several of these frequencies have a high sensitivity to the land surface and they also have the capacity to penetrate clouds. These advantages come at the cost of the relatively coarse spatial resolution (footprints range from ~5 to ~50 km) which in turn allows for global monitoring. A relatively simple methodology to monitor the fraction of <span class="hlt">open</span> <span class="hlt">water</span> from AMSR2 observations is presented here. Low frequency passive microwave observations have sensitivity to the land surface but are modulated by overlying signals from physical temperature and vegetation cover. We developed a completely microwave based artificial neural network supported by physically based components to monitor the fraction of <span class="hlt">open</span> <span class="hlt">water</span>. Three different areas, located in China, Southeast Asia and Australia, were selected for testing purposes and several different characteristics were examined. First, the overall performance of the methodology was evaluated against the NASA NRT Global Flood Mapping system. Second, the skills of the various different AMSR2 frequencies were tested and revealed that artificial contamination is a factor to consider. The different skills of the tested frequencies are of interest to apply the methodology to alternative passive microwave sensors. This will be of benefit in using the numerous multi-frequency passive microwaves sensors currently observing our Earth</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013JGRC..118.4334A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013JGRC..118.4334A"><span>Estimating the Bowen ratio over the <span class="hlt">open</span> and ice-covered <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Andreas, Edgar L.; Jordan, Rachel E.; Mahrt, Larry; Vickers, Dean</p> <p>2013-09-01</p> <p>The Bowen ratio, the ratio of the turbulent surface fluxes of sensible (Hs) and latent (HL) heat, Bo ≡ Hs/HL, occurs throughout micrometeorology. It finds application in the Bowen ratio and energy budget method, where it provides both turbulent heat fluxes when only the available energy at the surface is known. It can yield an estimate of a missing Hs or HL if the other flux is known. We also suggest that the Bowen ratio may provide the missing piece needed to infer the surface sensible heat flux from satellite data. For this study, we analyze almost 9000 eddy-covariance measurements of Hs and HL. About half were made over sea ice; the other half, over the <span class="hlt">open</span> <span class="hlt">ocean</span>. These are saturated surfaces where the surface specific humidity is the saturation value at the surface temperature. Surface temperatures ranged from -44°C to 32°C and predict the Bowen ratio through the Bowen ratio indicator, Bo*=cp/>(Lv∂Qsat/∂Θ>)|Θs. Here cp is the specific heat of air at constant pressure, Lv is the latent heat of sublimation or vaporization, and ∂Qsat/∂Θ is the derivative of the saturation specific humidity (Qsat) with temperature (Θ). All quantities are evaluated at the surface temperature, Θs. Although Hs and HL can occur in nine possible combinations, in our data set, three combinations represent over 90% of the cases: Hs > 0 and HL > 0, Hs < 0 and HL < 0, and Hs < 0 and HL > 0. In each of these three cases, the data suggest Bo=aBo*, where a is 0.40, 3.27, and -0.65, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16351847','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16351847"><span>Finding food in the <span class="hlt">open</span> <span class="hlt">ocean</span>: foraging strategies in Humboldt penguins.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Culik, B</p> <p>2001-01-01</p> <p>Penguins are excellent "model" organisms allowing us to study the behaviour of marine homeotherms at sea. Penguins regularly return to their breeding colonies, enabling biologists to equip them with remote sensing devices such as physiological or behavioural data-loggers, radio- or satellite transmitters. Foraging trips at sea can last from days to weeks and after return of the birds to their breeding sites, the devices can easily be removed for analysis of on-board stored data, yielding a wealth of information. Investigation of penguin behaviour at sea becomes particularly revealing when other sources of information can be matched to the data set, such as satellite data on wind, temperature, ice cover, and chlorophyll-a concentrations. Penguins and other marine homeotherms are true inhabitants of the high seas. Depending on the season, the marine behaviour varies: during reproduction, penguins are central-place foragers, and must return regularly to their nest to feed their chicks. During the remainder of the year, there are no constraints and the birds travel large distances at sea. Breeding Humboldt penguins react to climatic change by varying their daily foraging range and dive duration. Similar to other representatives of the family Spheniscidae, Humboldt penguins avoid food shortages by migrating into more productive marine areas. Navigational clues such as daylength, sea surface temperature, local wind direction and olfaction might provide important aids in finding patchily distributed prey in the <span class="hlt">open</span> <span class="hlt">ocean</span>. DMS, a chemical compound produced by decaying algae, seems to be a further clue that indirectly points the way to feeding areas.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009EGUGA..11.7150E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009EGUGA..11.7150E"><span>Reactivation of Pan-African structures during the <span class="hlt">opening</span> of the proto Indian <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Emmel, B.; Jacobs, J.; Ueda, K.; Jöns, N.; Lisker, F.</p> <p>2009-04-01</p> <p>During late Neoproterozoic - early Cambrian times (Pan-African) Gondwana amalgamated along the East African Orogen, its continuation into East Antarctica and the Kuunga Orogen. East Africa, Madagascar, the Indian - Seychelles block, Sri Lanka and East Antarctica were welded together and formed the Gondwana supercontinent. Approximately 350 Myr later the supercontinent broke into its original fragments and the proto Indian <span class="hlt">Ocean</span> was <span class="hlt">opened</span>. Paleo-reconstructions from Cambrian to Mesozoic times show that the separation of the Gondwana fragments took place along the late Neoproterozoic - early Cambrian organic junctions indicating that structures related to the amalgamation were used during the break-up. Today, mid-crustal remnants of the Pan African organic roots are exposed to surface conditions as metamorphic basement rocks with some well defined structural anisotropies like ductile high strain or major shear zones. Field evidences for structural reactivation within these zones are sparse, thus geochronological and thermochronological data are needed to constraint the cooling history of the high strain zones and the basement blocks bounded by them. Examples of combined structural field and remote sensing data together with fission track age distribution maps from Sri Lanka, northern Mozambique and Madagascar show the significance of structural inheritance (e.g., south-western Highland Complex, Lurio Belt, Ampanihy, Ejeda and Ranotsara shear zones) on the later continental margin formation within the reactivated older orogens during post Pan-African times. Apatite fission track data indicate two main rock cooling episodes in the upper crustal level during the Carboniferous-Permian and the Cretaceous related to intracontinental rifting within Gondwana and the Cretaceous geodynamic reorganization when India started its drift northwards.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160014496&hterms=Ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DOcean','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160014496&hterms=Ocean&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DOcean"><span>The <span class="hlt">Open-Ocean</span> Sensible Heat Flux and Its Significance for Arctic Boundary Layer Mixing During Early Fall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ganeshan, Manisha; Wu, Dongliang</p> <p>2016-01-01</p> <p>The increasing ice-free area during late summer has transformed the Arctic to a climate system with more dynamic boundary layer (BL) clouds and seasonal sea ice growth. The <span class="hlt">open-ocean</span> sensible heat flux, a crucial mechanism of excessive <span class="hlt">ocean</span> heat loss to the atmosphere during the fall freeze season, is speculated to play an important role in the recently observed cloud cover increase and BL instability. However, lack of observations and understanding of the resilience of the proposed mechanisms, especially in relation to meteorological and interannual variability, has left a poorly constrained BL parameterization scheme in Arctic climate models. In this study, we use multiyear Japanese cruise-ship observations from RV Mirai over the <span class="hlt">open</span> Arctic <span class="hlt">Ocean</span> to characterize the surface sensible heat flux (SSHF) during early fall and investigate its contribution to BL turbulence. It is found that mixing by SSHF is favored during episodes of high surface wind speed and is also influenced by the prevailing cloud regime. The deepest BLs and maximum <span class="hlt">ocean</span>-atmosphere temperature difference are observed during cold air advection (associated with the stratocumulus regime), yet, contrary to previous speculation, the efficiency of sensible heat exchange is low. On the other hand, the SSHF contributes significantly to BL mixing during the uplift (low pressure) followed by the highly stable (stratus) regime. Overall, it can explain 10 of the <span class="hlt">open</span> <span class="hlt">ocean</span> BL height variability, whereas cloud-driven (moisture and radiative) mechanisms appear to be the other dominant source of convective turbulence. Nevertheless, there is strong interannual variability in the relationship between the SSHF and the BL height which can be intensified by the changing occurrence of Arctic climate patterns, such as positive surface wind speed anomalies and more frequent conditions of uplift. This study highlights the need for comprehensive BL observations like the RV Mirai for better understanding and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ACP....1613173G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ACP....1613173G"><span>The <span class="hlt">open-ocean</span> sensible heat flux and its significance for Arctic boundary layer mixing during early fall</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Ganeshan, Manisha; Wu, Dong L.</p> <p>2016-10-01</p> <p>The increasing ice-free area during late summer has transformed the Arctic to a climate system with more dynamic boundary layer (BL) clouds and seasonal sea ice growth. The <span class="hlt">open-ocean</span> sensible heat flux, a crucial mechanism of excessive <span class="hlt">ocean</span> heat loss to the atmosphere during the fall freeze season, is speculated to play an important role in the recently observed cloud cover increase and BL instability. However, lack of observations and understanding of the resilience of the proposed mechanisms, especially in relation to meteorological and interannual variability, has left a poorly constrained BL parameterization scheme in Arctic climate models. In this study, we use multi-year Japanese cruise-ship observations from R/V Mirai over the <span class="hlt">open</span> Arctic <span class="hlt">Ocean</span> to characterize the surface sensible heat flux (SSHF) during early fall and investigate its contribution to BL turbulence. It is found that mixing by SSHF is favored during episodes of high surface wind speed and is also influenced by the prevailing cloud regime. The deepest BLs and maximum <span class="hlt">ocean</span>-atmosphere temperature difference are observed during cold air advection (associated with the stratocumulus regime), yet, contrary to previous speculation, the efficiency of sensible heat exchange is low. On the other hand, the SSHF contributes significantly to BL mixing during the uplift (low pressure) followed by the highly stable (stratus) regime. Overall, it can explain ˜ 10 % of the <span class="hlt">open-ocean</span> BL height variability, whereas cloud-driven (moisture and radiative) mechanisms appear to be the other dominant source of convective turbulence. Nevertheless, there is strong interannual variability in the relationship between the SSHF and the BL height which can be intensified by the changing occurrence of Arctic climate patterns, such as positive surface wind speed anomalies and more frequent conditions of uplift. This study highlights the need for comprehensive BL observations like the R/V Mirai for better understanding and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20160014496&hterms=Arctic+Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DArctic%2BOcean','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20160014496&hterms=Arctic+Ocean&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DArctic%2BOcean"><span>The <span class="hlt">Open-Ocean</span> Sensible Heat Flux and Its Significance for Arctic Boundary Layer Mixing During Early Fall</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ganeshan, Manisha; Wu, Dongliang</p> <p>2016-01-01</p> <p>The increasing ice-free area during late summer has transformed the Arctic to a climate system with more dynamic boundary layer (BL) clouds and seasonal sea ice growth. The <span class="hlt">open-ocean</span> sensible heat flux, a crucial mechanism of excessive <span class="hlt">ocean</span> heat loss to the atmosphere during the fall freeze season, is speculated to play an important role in the recently observed cloud cover increase and BL instability. However, lack of observations and understanding of the resilience of the proposed mechanisms, especially in relation to meteorological and interannual variability, has left a poorly constrained BL parameterization scheme in Arctic climate models. In this study, we use multiyear Japanese cruise-ship observations from RV Mirai over the <span class="hlt">open</span> Arctic <span class="hlt">Ocean</span> to characterize the surface sensible heat flux (SSHF) during early fall and investigate its contribution to BL turbulence. It is found that mixing by SSHF is favored during episodes of high surface wind speed and is also influenced by the prevailing cloud regime. The deepest BLs and maximum <span class="hlt">ocean</span>-atmosphere temperature difference are observed during cold air advection (associated with the stratocumulus regime), yet, contrary to previous speculation, the efficiency of sensible heat exchange is low. On the other hand, the SSHF contributes significantly to BL mixing during the uplift (low pressure) followed by the highly stable (stratus) regime. Overall, it can explain 10 of the <span class="hlt">open</span> <span class="hlt">ocean</span> BL height variability, whereas cloud-driven (moisture and radiative) mechanisms appear to be the other dominant source of convective turbulence. Nevertheless, there is strong interannual variability in the relationship between the SSHF and the BL height which can be intensified by the changing occurrence of Arctic climate patterns, such as positive surface wind speed anomalies and more frequent conditions of uplift. This study highlights the need for comprehensive BL observations like the RV Mirai for better understanding and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25208126','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25208126"><span>Nitrate removal in shallow, <span class="hlt">open-water</span> treatment wetlands.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Jasper, Justin T; Jones, Zackary L; Sharp, Jonathan O; Sedlak, David L</p> <p>2014-10-07</p> <p>The diffuse biomat formed on the bottom of shallow, <span class="hlt">open-water</span> unit process wetland cells contains suboxic zones that provide conditions conducive to NO3(-) removal via microbial denitrification, as well as anaerobic ammonium oxidation (anammox). To assess these processes, nitrogen cycling was evaluated over a 3-year period in a pilot-scale wetland cell receiving nitrified municipal wastewater effluent. NO3(-) removal varied seasonally, with approximately two-thirds of the NO3(-) entering the cell removed on an annual basis. Microcosm studies indicated that NO3(-) removal was mainly attributable to denitrification within the diffuse biomat (i.e., 80 ± 20%), with accretion of assimilated nitrogen accounting for less than 3% of the NO3(-) removed. The importance of denitrification to NO3(-) removal was supported by the presence of denitrifying genes (nirS and nirK) within the biomat. While modest when compared to the presence of denitrifying genes, a higher abundance of the anammox-specific gene hydrazine synthase (hzs) at the biomat bottom than at the biomat surface, the simultaneous presence of NH4(+) and NO3(-) within the biomat, and NH4(+) removal coupled to NO2(-) and NO3(-) removal in microcosm studies, suggested that anammox may have been responsible for some NO3(-) removal, following reduction of NO3(-) to NO2(-) within the biomat. The annual temperature-corrected areal first-order NO3(-) removal rate (k20 = 59.4 ± 6.2 m yr(-1)) was higher than values reported for more than 75% of vegetated wetlands that treated <span class="hlt">water</span> in which NO3(-) was the primary nitrogen species (e.g., nitrified secondary wastewater effluent and agricultural runoff). The inclusion of <span class="hlt">open-water</span> cells, originally designed for the removal of trace organic contaminants and pathogens, in unit-process wetlands may enhance NO3(-) removal as compared to existing vegetated wetland systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4313803','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4313803"><span>Genomic and proteomic characterization of “Candidatus Nitrosopelagicus brevis”: An ammonia-oxidizing archaeon from the <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Santoro, Alyson E.; Dupont, Christopher L.; Richter, R. Alex; Craig, Matthew T.; Carini, Paul; McIlvin, Matthew R.; Yang, Youngik; Orsi, William D.; Moran, Dawn M.; Saito, Mak A.</p> <p>2015-01-01</p> <p>Thaumarchaeota are among the most abundant microbial cells in the <span class="hlt">ocean</span>, but difficulty in cultivating marine Thaumarchaeota has hindered investigation into the physiological and evolutionary basis of their success. We report here a closed genome assembled from a highly enriched culture of the ammonia-oxidizing pelagic thaumarchaeon CN25, originating from the <span class="hlt">open</span> <span class="hlt">ocean</span>. The CN25 genome exhibits strong evidence of genome streamlining, including a 1.23-Mbp genome, a high coding density, and a low number of paralogous genes. Proteomic analysis recovered nearly 70% of the predicted proteins encoded by the genome, demonstrating that a high fraction of the genome is translated. In contrast to other minimal marine microbes that acquire, rather than synthesize, cofactors, CN25 encodes and expresses near-complete biosynthetic pathways for multiple vitamins. Metagenomic fragment recruitment indicated the presence of DNA sequences >90% identical to the CN25 genome throughout the oligotrophic <span class="hlt">ocean</span>. We propose the provisional name “Candidatus Nitrosopelagicus brevis” str. CN25 for this minimalist marine thaumarchaeon and suggest it as a potential model system for understanding archaeal adaptation to the <span class="hlt">open</span> <span class="hlt">ocean</span>. PMID:25587132</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25587132','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25587132"><span>Genomic and proteomic characterization of "Candidatus Nitrosopelagicus brevis": an ammonia-oxidizing archaeon from the <span class="hlt">open</span> <span class="hlt">ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Santoro, Alyson E; Dupont, Christopher L; Richter, R Alex; Craig, Matthew T; Carini, Paul; McIlvin, Matthew R; Yang, Youngik; Orsi, William D; Moran, Dawn M; Saito, Mak A</p> <p>2015-01-27</p> <p>Thaumarchaeota are among the most abundant microbial cells in the <span class="hlt">ocean</span>, but difficulty in cultivating marine Thaumarchaeota has hindered investigation into the physiological and evolutionary basis of their success. We report here a closed genome assembled from a highly enriched culture of the ammonia-oxidizing pelagic thaumarchaeon CN25, originating from the <span class="hlt">open</span> <span class="hlt">ocean</span>. The CN25 genome exhibits strong evidence of genome streamlining, including a 1.23-Mbp genome, a high coding density, and a low number of paralogous genes. Proteomic analysis recovered nearly 70% of the predicted proteins encoded by the genome, demonstrating that a high fraction of the genome is translated. In contrast to other minimal marine microbes that acquire, rather than synthesize, cofactors, CN25 encodes and expresses near-complete biosynthetic pathways for multiple vitamins. Metagenomic fragment recruitment indicated the presence of DNA sequences >90% identical to the CN25 genome throughout the oligotrophic <span class="hlt">ocean</span>. We propose the provisional name "Candidatus Nitrosopelagicus brevis" str. CN25 for this minimalist marine thaumarchaeon and suggest it as a potential model system for understanding archaeal adaptation to the <span class="hlt">open</span> <span class="hlt">ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSOD14B2414C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSOD14B2414C"><span>Investigating the Potential Impact of the Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) Altimeter on <span class="hlt">Ocean</span> Mesoscale Prediction</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carrier, M.; Ngodock, H.; Smith, S. R.; Souopgui, I.</p> <p>2016-02-01</p> <p>NASA's Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT) satellite, scheduled for launch in 2020, will provide sea surface height anomaly (SSHA) observations with a wider swath width and higher spatial resolution than current satellite altimeters. It is expected that this will help to further constrain <span class="hlt">ocean</span> models in terms of the mesoscale circulation. In this work, this expectation is investigated by way of twin data assimilation experiments using the Navy Coastal <span class="hlt">Ocean</span> Model Four Dimensional Variational (NCOM-4DVAR) data assimilation system using a weak constraint formulation. Here, a nature run is created from which SWOT observations are sampled, as well as along-track SSHA observations from simulated Jason-2 tracks. The simulated SWOT data has appropriate spatial coverage, resolution, and noise characteristics based on an observation-simulator program provided by the SWOT science team. The experiment is run for a three-month period during which the analysis is updated every 24 hours and each analysis is used to initialize a 96 hour forecast. The forecasts in each experiment are compared to the available nature run to determine the impact of the assimilated data. It is demonstrated here that the SWOT observations help to constrain the model mesoscale in a more consistent manner than traditional altimeter observations. The findings of this study suggest that data from SWOT may have a substantial impact on improving the <span class="hlt">ocean</span> model analysis and forecast of mesoscale features and surface <span class="hlt">ocean</span> transport.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28769035','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28769035"><span>Spiraling pathways of global deep <span class="hlt">waters</span> to the surface of the Southern <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tamsitt, Veronica; Drake, Henri F; Morrison, Adele K; Talley, Lynne D; Dufour, Carolina O; Gray, Alison R; Griffies, Stephen M; Mazloff, Matthew R; Sarmiento, Jorge L; Wang, Jinbo; Weijer, Wilbert</p> <p>2017-08-02</p> <p>Upwelling of global deep <span class="hlt">waters</span> to the sea surface in the Southern <span class="hlt">Ocean</span> closes the global overturning circulation and is fundamentally important for <span class="hlt">oceanic</span> uptake of carbon and heat, nutrient resupply for sustaining <span class="hlt">oceanic</span> biological production, and the melt rate of ice shelves. However, the exact pathways and role of topography in Southern <span class="hlt">Ocean</span> upwelling remain largely unknown. Here we show detailed upwelling pathways in three dimensions, using hydrographic observations and particle tracking in high-resolution models. The analysis reveals that the northern-sourced deep <span class="hlt">waters</span> enter the Antarctic Circumpolar Current via southward flow along the boundaries of the three <span class="hlt">ocean</span> basins, before spiraling southeastward and upward through the Antarctic Circumpolar Current. Upwelling is greatly enhanced at five major topographic features, associated with vigorous mesoscale eddy activity. Deep <span class="hlt">water</span> reaches the upper <span class="hlt">ocean</span> predominantly south of the Antarctic Circumpolar Current, with a spatially nonuniform distribution. The timescale for half of the deep <span class="hlt">water</span> to upwell from 30° S to the mixed layer is ~60-90 years.Deep <span class="hlt">waters</span> of the Atlantic, Pacific and Indian <span class="hlt">Oceans</span> upwell in the Southern Oceanbut the exact pathways are not fully characterized. Here the authors present a three dimensional view showing a spiralling southward path, with enhanced upwelling by eddy-transport at topographic hotspots.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..1616009B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..1616009B"><span>Vertical velocities associated with deep <span class="hlt">open-ocean</span> convection in the Northwestern Mediterranean Sea as indirectly observed by gliders</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bosse, Anthony; Testor, Pierre; Legland, Guillaume; Mortier, Laurent; Houpert, Loïc; Prieur, Louis</p> <p>2014-05-01</p> <p>During winter 2012-2013, deep <span class="hlt">open-ocean</span> convection occurred in the Gulf of Lions (Northwestern Mediterranean Sea) and has been thoroughly documented thanks to the deployment of several gliders at the same time, Argo profiling floats, dedicated ship cruises, and a mooring located within the mixed patch. The data collected represent an unprecedented density of profiles during a event of <span class="hlt">open-ocean</span> deep convection. We applied a method able to infer the vertical velocity signal from the glider navigation data. During active phase of mixing, the gliders faced significant vertical velocities (upward and downward displacement stronger than 10cm/s). Moving along a saw-tooth trajectory between the surface and 1000m, they could cross small scale convective plumes (L~1km) over a dive or ascent (2km and 2h between the surface and maximum depth), while recording temperature and salinity, as well as biogeochemical properties (dissolved oxygen, fluorescence, turbidity, ...). Our study provides a comprehensive dataset to get a characterization of convective plumes and a deeper understanding of their role in deep <span class="hlt">open-ocean</span> convection.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006AGUFMPP21D..02M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006AGUFMPP21D..02M"><span>Vertical <span class="hlt">Water</span> Mass Structure of the Southern <span class="hlt">Ocean</span> Inferred From Neodymium Isotopes: Implications for Organic Carbon Burial</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Martin, E. E.; Scher, H. D.</p> <p>2006-12-01</p> <p>Neodymium isotope records from the Atlantic sector of the Southern <span class="hlt">Ocean</span> have documented first order changes in <span class="hlt">ocean</span> circulation, such as Pacific throughflow following the early <span class="hlt">opening</span> of Drake Passage, initiation of deep <span class="hlt">water</span> export from the North Atlantic, and intensification of the Antarctic Circumpolar Current (ACC). These studies have shed light on changes in deep <span class="hlt">water</span> circulation and production areas, however the impact of these changes on the vertical structure of the Southern <span class="hlt">Ocean</span> is has not been explored. We investigated the middle Eocene to early Miocene sections of three vertically and horizontally offset <span class="hlt">Ocean</span> Drilling Program (ODP) sites in the Atlantic sector of the Southern <span class="hlt">Ocean</span> (ODP Sites 689 (upper Maud Rise; paleodepth 1500 m), 690 (lower Maud Rise; paleodepth 2200 m), and 1090 (Agulhas Ridge; paleodepth 3700). Nd isotope records were generated from fossil fish teeth covering the interval from 45 to 25 Ma. Our goal was to investigate changes in the vertical <span class="hlt">water</span> mass structure of the Atlantic sector of the Southern <span class="hlt">Ocean</span>. The vertical <span class="hlt">water</span> mass structure of the Southern <span class="hlt">Ocean</span> has been influenced by the development of the ACC, which is believed to have exerted an important control on the relationship between opal deposition and organic carbon burial in this region. Thus, this work is relevant for assessing the mechanisms thought to be responsible for the draw down of atmospheric carbon dioxide, an important factor in global climate change over this interval. During the middle Eocene, around 42 Ma, the ɛNd gradient between intermediate and deep <span class="hlt">waters</span> in the Atlantic sector was about 1 ɛNd unit. ɛNd values at Maud Rise were -9.2 and - 9.5 (Sites 689 and 690 respectively), while ɛNd values at Agulhas Ridge were -8.5. Between 41 and 35 Ma ɛNd values at all three locations became more radiogenic as Pacific seawater entered the Atlantic following the early <span class="hlt">opening</span> of Drake Passage. Agulhas Ridge ɛNd values increased to -6, and values at</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005DSRII..52..727Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005DSRII..52..727Y"><span>Linkages between coastal and <span class="hlt">open-ocean</span> habitats and dynamics of Japanese stocks of chum salmon and Japanese sardine</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yatsu, Akihiko; Kaeriyama, Masahide</p> <p>2005-03-01</p> <p>Coastal-<span class="hlt">ocean-open-ocean</span> migrations, prey-predator relations and long-term population dynamics of chum salmon ( Oncorhynchus keta) and Japanese sardine ( Sardinops melanostictus), associated with large-scale climate and oceanographic conditions, are reviewed. After early marine life in coastal <span class="hlt">waters</span> in northern Japan, chum salmon of Japanese origin spend their first summer in the Okhotsk Sea, then move to the Western Subarctic Gyre for the first winter at sea. Thereafter, they migrate between summer feeding grounds in the Bering Sea and wintering grounds in the Alaskan Gyre for a period of usually up to four years, and finally return to their natal rivers to spawn. Carrying capacity ( K) for chum salmon at an unfished equilibrium level was estimated from a Ricker spawner-recruitment curve, and the residual carrying capacity ( RCC=(K-abundance)K-1). was positively correlated with body size at age 4, and negatively correlated with age at maturity. Marine survival of Hokkaido chum populations was affected by body size at release, but neither by Aleutian low pressure activity nor sea-surface temperature (SST) around coastal Hokkaido in spring, although there is some correlation between survival rate and coastal SST. Juveniles of the Pacific stock of Japanese sardine become broadly distributed in the Kuroshio Extension (KE) as far east as 180° longitude during spring. Adults disperse as far as the central Pacific and the southern areas of the Okhotsk Sea and Western Subarctic Gyre in years of high abundance. Somatic growth and age at maturation of sardine are density-dependent. We used catch, biomass and residuals of observed recruitment numbers from a Ricker curve (LNRR) as a measure of sardine population dynamics. LNRR was highly correlated with SST of KE in winter, which shifted in 1970 and 1988. Recent biomass and catch remain at extremely low levels due to a combination of adverse environmental conditions and intensive fishing. We suggest that Japanese</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSCT41A..04M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSCT41A..04M"><span>Mercury Stable Isotopes Reveal Deep Methylation of Mercury and its Uptake into the <span class="hlt">Open</span> <span class="hlt">Ocean</span> Food Web</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Motta, L. C.; Blum, J. D.; Johnson, M. W.; Popp, B. N.; Drazen, J.; Hannides, C. C.; Close, H. G.; Umhau, B.; benitez-Nelson, C. R.</p> <p>2016-02-01</p> <p>Knowledge of the biogeochemistry of methylmercury (MeHg) is required to understand its biomagnification in <span class="hlt">open</span> <span class="hlt">ocean</span> food webs. Mass dependent (MDF; δ202Hg) and mass independent (MIF; Δ199Hg) fractionation of Hg isotopes provides new insight into sources and transformations of marine Hg. We measured Hg isotope ratios of fish, zooplankton and sinking particles in vertical profiles at Station ALOHA in the North Pacific Subtropical Gyre. Fish display large decreases in δ202Hg (1.6 to -0.2‰) and Δ199Hg (5.3 to 0.8‰) between 10 and 800 m mean feeding depth. Zooplankton also display decreases in δ202Hg (0.2 to -0.3‰) and Δ199Hg (2.2 to 0.8 ‰) between 25 and 1250 m depth, although not as large as in fish. In contrast, sinking particles (> 53 mm) display little variation in δ202Hg (-0.1 to -0.2‰) and Δ199Hg (0.1 to 0.3‰) between 50 and 400 m depth. Precipitation near Hawaii has δ202Hg (0.1 to 0.2‰) and Δ199Hg (0.2 to 0.4‰) similar to sinking particles. We developed a preliminary conceptual model to explain these observations. Inorganic Hg (IHg) is deposited to the <span class="hlt">ocean</span> via precipitation, sorbs to sinking particles and is transported to ≥ 400 m depth without enough methylation or photochemical reduction to shift δ202Hg or Δ199Hg values appreciably. MeHg is formed and partially photo-demethylated in the photic zone: a small proportion of this also attaches to particles. Shallow zooplankton bioaccumulate MeHg more efficiently than IHg from particles and therefore acquire δ202Hg and Δ199Hg values midway between the values of MeHg (the value of surface feeding fish) and IHg (the value of precipitation). Some methylation also occurs within IHg-dominated particles as they sink to deeper <span class="hlt">waters</span>; this new MeHg lacks the isotopic signature of photo-demethylation. At about 800 m depth the values of δ202Hg and Δ199Hg in fish and zooplankton converge, suggesting that deep IHg and MeHg have similar isotopic values, and that most MeHg in these</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSAH21A..08M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSAH21A..08M"><span><span class="hlt">Ocean</span> Acidification in the Surface <span class="hlt">Waters</span> of the Pacific-Arctic Boundary Regions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mathis, J. T.; Cross, J. N.; Evans, W.; Doney, S. C.</p> <p>2016-02-01</p> <p>The continental shelves of the Pacific-Arctic Region (PAR) are especially vulnerable to the effects of <span class="hlt">ocean</span> acidification (OA) because the intrusion of anthropogenic CO2 is not the only process that can reduce pH and carbonate mineral saturation states for aragonite (ΩArag). Enhanced sea-ice melt, respiration of organic matter, upwelling and riverine inputs have been shown to exacerbate CO2-driven <span class="hlt">ocean</span> acidification in high-latitude regions. Additionally, the indirect effect of changing sea-ice coverage is providing a positive feedback to OA as more <span class="hlt">open</span> <span class="hlt">water</span> will allow for greater uptake of atmospheric CO2. Here, we compare model-based outputs from the Community Earth System Model with a subset of recent ship-based observations, and take an initial look at future model projections of surface <span class="hlt">water</span> ΩArag in the Bering, Chukchi and Beaufort Seas. We then use the model outputs to define benchmark years when biological impacts are likely to result from reduced ΩArag. Each of the three continental shelf seas in the PAR will become undersaturated with respect to aragonite at approximately 30-year intervals, indicating that aragonite undersaturations gradually progress upstream along the flow path of the <span class="hlt">waters</span> as they move north from the Pacific <span class="hlt">Ocean</span>. However, naturally high variability in ΩArag may indicate higher resilience of the Bering Sea ecosystem to these low-ΩArag conditions than the Chukchi and the Beaufort Seas. Based on our initial results, we have determined that the annual mean for ΩArag will pass below the current range of natural variability in 2025 for the Beaufort Sea and 2027 for the Chukchi Sea. Because of the higher range of natural variability, the annual mean for ΩArag for the Bering Sea does not pass out of the natural variability range until 2044. As ΩArag in these shelf seas slips below the present-day range of large seasonal variability by midcentury, it could put tremendous pressure on the diverse ecosystems that support some of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1984STIN...8519542M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1984STIN...8519542M"><span>OTEC (<span class="hlt">Ocean</span> Thermal Energy Conversion) Cold <span class="hlt">Water</span> Pipe At-Sea Test Program. Phase 2: Suspended pipe test</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>McHale, F. A.</p> <p>1984-08-01</p> <p>An important step in the development of technology for <span class="hlt">Ocean</span> Thermal Energy Conversion (OTEC) cold <span class="hlt">water</span> pipes (CWP) is the at-sea testing and subsequent evaluation of a large diameter fiberglass reinforced plastic (FRP) pipe. Focus was on the CWP since it is the most critical element in any OTEC design. The results of the second phase of the CWP At-Sea Test Program are given. During this phase an 8 foot diameter, 400 foot long sandwich wall FRP syntactic foam configuration CWP test article was developed, constructed, deployed and used for data acquisition in the <span class="hlt">open</span> <span class="hlt">ocean</span> near Honolulu, Hawaii. This instrumented CWP as suspended from a moored platform for a three week experiment in April-May, 1983. The CWP represented a scaled version of a 40 megawatt size structure, nominally 30 feet in diameter and 3000 feet long.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27943286','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27943286"><span>New and historical records of the <span class="hlt">ocean</span> sunfish Mola mola in Icelandic <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Palsson, J; Astthorsson, O S</p> <p>2017-03-01</p> <p>The <span class="hlt">ocean</span> sunfish Mola mola is considered to be globally distributed in both temperate and tropical <span class="hlt">waters</span>, but there are many gaps in the knowledge of this species' distribution. A total of 31 records of M. mola from Icelandic <span class="hlt">waters</span>, dating from 1845 to 2014, are presented and georeferenced. An increase in the number of records at the beginning of this century and particularly in 2012, is suggested to be a consequence of both an increase in <span class="hlt">ocean</span> temperature on the Icelandic shelf and changes in large scale temperature variations in the North Atlantic <span class="hlt">Ocean</span>. © 2016 The Fisheries Society of the British Isles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014EGUGA..16.6940J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014EGUGA..16.6940J"><span>An improved wet tropospheric correction for CryoSat-2 over <span class="hlt">open</span> and coastal <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Joana Fernandes, M.; Lázaro, Clara; Nunes, Alexandra L.; Pires, Nelson; Dinardo, Salvatore; Benveniste, Jérôme</p> <p>2014-05-01</p> <p>In the scope of the CryoSat Plus for <span class="hlt">Oceans</span> (CP4O) project, encouraged by the European Space Agency, a data combination (DComb) algorithm has been developed for the computation of the wet tropospheric correction (WTC) for CryoSat-2, which does not possess an onboard microwave radiometer (MWR), thus relying on a model-based WTC provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). This WTC is based on the objective analysis of all available wet path delay data sources (e.g. from scanning imaging MWR (SI MWR) on board remote sensing satellites, those derived from Global Navigation Satellite Systems (GNSS) measurements at coastal stations and from an atmospheric model such as the ECMWF ReAnalysis (ERA) Interim. This presentation gives a brief description of the DComb algorithm and its application to CryoSat-2. The algorithm was first applied to Jason-2 and compared with the correction from the Jason-2 advanced microwave radiometer (AMR) present on the version D of the Geophysical Data Records (GDR-D), known to be a well calibrated and accurate correction, with improved performance in coastal regions. These results show that for epochs and locations for which SI-MWR measurements are available, the DComb WTC is very similar to that of AMR, evidencing that the SI-MWR <span class="hlt">water</span> vapour products, previously calibrated with respect to AMR, are an extremely valuable data set for the estimation of the WTC for any altimeter mission, including those which possess an onboard MWR. For both Jason-2 and CryoSat-2 the new correction was validated through analysis of sea level anomaly variance at crossovers, function of distance from the coast and latitude. The influence of the GNSS-derived wet path delays in the coastal regions, of major importance for the full exploitation of CryoSat-2 data, in particular those acquired in the Synthetic Aperture Radar (SAR) mode, is also shown.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017EGUGA..19.1948A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017EGUGA..19.1948A"><span>Does size matter in peatland <span class="hlt">open-water</span> pool biogeochemistry?</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Arsenault, Julien; Talbot, Julie; Moore, Tim R.</p> <p>2017-04-01</p> <p><span class="hlt">Open-water</span> pools are common features in boreal peatlands but their influence on ecosystem biogeochemistry is poorly known. As nitrogen (N) and phosphorus (P) are often limited in such environments, nutrient cycles in pools might have an effect on the surrounding peat, or vice versa. We studied C, N and P biogeochemistry in <span class="hlt">open-water</span> pools of an undisturbed sub-boreal ombrotrophic peatland in Québec, Canada. We assessed the relationship between the pool's physical characteristics and biogeochemistry, and quantified the temporal evolution of C, N and P concentrations in pools of different size and depth over a growing season. A one-time survey of 62 of the ˜650 pools in the peatland revealed that pool depth and area vary from 0.15 to 2.19 m and from 34 to 1977 m2, respectively. Dissolved organic carbon (DOC) concentration ranged from 8.6 to 36.9 mg L-1, negatively correlated to pool depth, and pH varied from 3.72 to 4.33. Total P was extremely low (mean = 17.3 μg L-1) in all pools and total N (0.71 to 0.27 mg L-) was negatively correlated with pool depth. Nine pools, selected to represent extremes in depth and area, were surveyed every 2 to 3 weeks from mid-May to late October, 2016. Average DOC concentrations slightly increased in deep pools from 10.0 mg L-1 in May to 15.6 mg L-1 in October, but there was a stronger increase in shallow pools (from 15.4 to 33.5 mg L-1). <span class="hlt">Water</span> acidity tended to increase in large and small shallow pools (mean pH = 4.02 to 3.81) but decreased in deep pools (pH = 4.17 to 4.46). Mean total P ranged from 37.7 in May to 16.3 μg L-1 in October with a minimum of 8.0 μg L-1 in mid-August. Total N tended to increase (0.27 to 0.53 mg L-1) in all pools, but deeper pools tended to have lower total N (0.25 to 0.46 mg L-1) than shallow pools. Throughout, NH4+ (mean = 9 μg L-1) and soluble reactive phosphorus (mean = 7 μg L-1) were extremely low in all pools. In May, NO3- was higher in deep pools (42.3 μg L-1) than in shallow pools (large 12</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/ds/0928/ds928_abstract.html','USGSPUBS'); return false;" href="https://pubs.usgs.gov/ds/0928/ds928_abstract.html"><span>Back-island and <span class="hlt">open-ocean</span> shorelines, and sand areas of Assateague Island, Maryland and Virginia, April 12, 1989, to September 5, 2013</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Guy, Kristy K.</p> <p>2015-01-01</p> <p>This Data Series Report includes several <span class="hlt">open-ocean</span> shorelines, back-island shorelines, back-island shoreline points, sand area polygons, and sand lines for Assateague Island that were extracted from natural-color orthoimagery (aerial photography) dated from April 12, 1989, to September 5, 2013. The images used were 0.3–2-meter (m)-resolution U.S. Geological Survey Digital Orthophoto Quarter Quads (DOQQ), U.S. Department of Agriculture National Agriculture Imagery Program (NAIP) images, and Virginia Geographic Information Network Virginia Base Map Program (VBMP) images courtesy of the Commonwealth of Virginia. The back-island shorelines were hand-digitized at the intersect of the apparent back-island shoreline and transects spaced at 20-m intervals. The <span class="hlt">open-ocean</span> shorelines were hand-digitized at the approximate still <span class="hlt">water</span> level, such as tide level, which was fit through the average position of waves and swash apparent on the beach. Hand-digitizing was done at a scale of approximately 1:2,000. The sand polygons were derived by using an image-processing unsupervised classification technique that separates images into classes. The classes were then visually categorized as either sand or not sand. Also included in this report are 20-m-spaced transect lines and the transect base lines.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23444851','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23444851"><span>A commercial trial evaluating three <span class="hlt">open</span> <span class="hlt">water</span> sources for farmed ducks: effects on <span class="hlt">water</span> usage and <span class="hlt">water</span> quality.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Liste, G; Kirkden, R D; Broom, D M</p> <p>2013-01-01</p> <p>1. Providing <span class="hlt">open</span> <span class="hlt">water</span> to farmed ducks is beneficial for their health and behaviour but, at commercial densities, may also have negative consequences for the health of the ducks, the productivity of the farms and environmental contamination. 2. The current experiment investigated the suitability of three types of <span class="hlt">open</span> <span class="hlt">water</span> resources in a commercial setting, assessing their effects on <span class="hlt">water</span> usage and <span class="hlt">water</span> quality. The three resources were: narrow troughs (15 cm wide and 8 cm deep), intermediate troughs (20 cm wide and 12 cm deep) and wide troughs (50 cm wide and 8 cm deep). A total of 23 flocks of ducks with a mean size of 4,540 ± 680 individuals and a final stocking density less than 17 kg/m(2) were studied. 3. Intermediate troughs used twice as much <span class="hlt">water</span> as narrow troughs and wide troughs. Intermediate troughs had the best microbiological <span class="hlt">water</span> quality, wide troughs had the worst physical and microbiological quality and narrow troughs tended to be intermediate. 4. <span class="hlt">Open</span> <span class="hlt">water</span> provision resulted in high <span class="hlt">water</span> usage, but this might be reduced by further investigating cleaning regimes, ballcock systems and the volumetric capacity of the troughs. It was difficult to maintain good <span class="hlt">water</span> quality, and more research is needed to investigate the long term effects on productivity and public health.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA546943','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA546943"><span>Global Shallow-<span class="hlt">Water</span> Bathymetry from Satellite <span class="hlt">Ocean</span> Color Data</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2010-11-16</p> <p>muiine powei plant planning understanding HI censsstem connect ivm coustul management and change analyses Because <span class="hlt">ocean</span> .ire.is are enormousl) Lute and...spectral data, satellite altimetry, <span class="hlt">ocean</span> bathymetry 16. SECURITY CLASSIFICATION OF a REPORT I nclassified b ABSTRACT Unclassified c THIS...tiv.’rtinK.’llirisiiiliimultl • •.sill M . till’ |MII ’i »rilli itil |i - «r •’•’ I llu N.is|tlr.-tt II. .... iutta "" HUB; HHMH s-| -tr.n</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PrOce.132...22R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PrOce.132...22R"><span>Arctic <span class="hlt">Ocean</span> circulation, processes and <span class="hlt">water</span> masses: A description of observations and ideas with focus on the period prior to the International Polar Year 2007-2009</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rudels, Bert</p> <p>2015-03-01</p> <p>The evolving knowledge of the Arctic <span class="hlt">Ocean</span>, its hydrography and its <span class="hlt">water</span> masses and their transformations and circulation is reviewed starting with the observations made on Fram 1893-1896 and extending to the International Polar Year (IPY) 2007-2009. The expeditions and observations after Fram to the mid 20th century as well as the more extensive and systematic studies of <span class="hlt">water</span> masses and circulation made from ice stations and airborne expeditions from the late 1940s to the late 1970s are briefly described. The early concepts of the connections and exchanges between the Arctic <span class="hlt">Ocean</span> and the world <span class="hlt">ocean</span> are also discussed. In the 1980s scientific icebreakers were beginning to enter the inner parts of the Arctic <span class="hlt">Ocean</span> and large international programmes were launched, culminating in the IPY. The changes in the Arctic <span class="hlt">Ocean</span>, first noted in the Atlantic layer in 1990 and shortly after in the upper layers, are described. The exchanges between the Arctic <span class="hlt">Ocean</span> and the surrounding seas through the four main <span class="hlt">openings</span>, Fram Strait, Barents Sea, Bering Strait and the Canadian Arctic Archipelago as well the volume and freshwater balances of the Arctic <span class="hlt">Ocean</span> are examined.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2011-title43-vol2/pdf/CFR-2011-title43-vol2-sec2091-5-4.pdf','CFR2011'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2011-title43-vol2/pdf/CFR-2011-title43-vol2-sec2091-5-4.pdf"><span>43 CFR 2091.5-4 - Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2011&page.go=Go">Code of Federal Regulations, 2011 CFR</a></p> <p></p> <p>2011-10-01</p> <p>... LAWS AND RULES Segregation and <span class="hlt">Opening</span> of Lands § 2091.5-4 Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals. 2091.5-4 Section 2091.5-4 Public Lands: Interior Regulations Relating to Public...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2013-title43-vol2/pdf/CFR-2013-title43-vol2-sec2091-5-4.pdf','CFR2013'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2013-title43-vol2/pdf/CFR-2013-title43-vol2-sec2091-5-4.pdf"><span>43 CFR 2091.5-4 - Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2013&page.go=Go">Code of Federal Regulations, 2013 CFR</a></p> <p></p> <p>2013-10-01</p> <p>... LAWS AND RULES Segregation and <span class="hlt">Opening</span> of Lands § 2091.5-4 Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals. 2091.5-4 Section 2091.5-4 Public Lands: Interior Regulations Relating to Public...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2014-title43-vol2/pdf/CFR-2014-title43-vol2-sec2091-5-4.pdf','CFR2014'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2014-title43-vol2/pdf/CFR-2014-title43-vol2-sec2091-5-4.pdf"><span>43 CFR 2091.5-4 - Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2014&page.go=Go">Code of Federal Regulations, 2014 CFR</a></p> <p></p> <p>2014-10-01</p> <p>... LAWS AND RULES Segregation and <span class="hlt">Opening</span> of Lands § 2091.5-4 Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals. 2091.5-4 Section 2091.5-4 Public Lands: Interior Regulations Relating to Public...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.gpo.gov/fdsys/pkg/CFR-2012-title43-vol2/pdf/CFR-2012-title43-vol2-sec2091-5-4.pdf','CFR2012'); return false;" href="https://www.gpo.gov/fdsys/pkg/CFR-2012-title43-vol2/pdf/CFR-2012-title43-vol2-sec2091-5-4.pdf"><span>43 CFR 2091.5-4 - Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals.</span></a></p> <p><a target="_blank" href="http://www.gpo.gov/fdsys/browse/collectionCfr.action?selectedYearFrom=2012&page.go=Go">Code of Federal Regulations, 2012 CFR</a></p> <p></p> <p>2012-10-01</p> <p>... LAWS AND RULES Segregation and <span class="hlt">Opening</span> of Lands § 2091.5-4 Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Segregative effect and <span class="hlt">opening</span>: <span class="hlt">Water</span> power withdrawals. 2091.5-4 Section 2091.5-4 Public Lands: Interior Regulations Relating to Public...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUFMOS41C1989M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUFMOS41C1989M"><span>Self-organization of hydrothermal outflow and recharge in young <span class="hlt">oceanic</span> crust: Constraints from <span class="hlt">open</span>-top porous convection analog experiments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mittelstaedt, E. L.; Olive, J. A. L.; Barreyre, T.</p> <p>2016-12-01</p> <p>Hydrothermal circulation at the axis of mid-<span class="hlt">ocean</span> ridges has a profound effect on chemical and biological processes in the deep <span class="hlt">ocean</span>, and influences the thermo-mechanical state of young <span class="hlt">oceanic</span> lithosphere. Yet, the geometry of fluid pathways beneath the seafloor and its relation to spatial gradients in crustal permeability remain enigmatic. Here we present new laboratory models of hydrothermal circulation aimed at constraining the self-organization of porous convection cells in homogeneous as well as highly heterogeneous crust analogs. <span class="hlt">Oceanic</span> crust analogs of known permeability are constructed using uniform glass spheres and 3-D printed plastics with a network of mutually perpendicular tubes. These materials are saturated with corn syrup-<span class="hlt">water</span> mixtures and heated at their base by a resistive silicone strip heater to initiate thermal convection. A layer of pure fluid (i.e., an analog <span class="hlt">ocean</span>) overlies the porous medium and allows an "<span class="hlt">open</span>-top" boundary condition. Areas of fluid discharge from the crust into the <span class="hlt">ocean</span> are identified by illuminating microscopic glass particles carried by the fluid, using laser sheets. Using particle image velocimetry, we estimate fluid discharge rates as well as the location and extent of fluid recharge. Thermo-couples distributed throughout the crust provide insights into the geometry of convection cells at depth, and enable estimates of convective heat flux, which can be compared to the heat supplied at the base of the system. Preliminary results indicate that in homogeneous crust, convection is largely confined to the narrow slot overlying the heat source. Regularly spaced discharge zones appear focused while recharge areas appear diffuse, and qualitatively resemble the along-axis distribution of hydrothermal fields at <span class="hlt">oceanic</span> spreading centers. By varying the permeability of the crustal analogs, the viscosity of the convecting fluid, and the imposed basal temperature, our experiments span Rayleigh numbers between 10 and 10</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24844123','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24844123"><span>Deep <span class="hlt">water</span> masses and sediments are main compartments for polychlorinated biphenyls in the Arctic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sobek, Anna; Gustafsson, Örjan</p> <p>2014-06-17</p> <p>There is a wealth of studies of polychlorinated biphenyls (PCB) in surface <span class="hlt">water</span> and biota of the Arctic <span class="hlt">Ocean</span>. Still, there are no observation-based assessments of PCB distribution and inventories in and between the major Arctic <span class="hlt">Ocean</span> compartments. Here, the first <span class="hlt">water</span> column distribution of PCBs in the central Arctic <span class="hlt">Ocean</span> basins (Nansen, Amundsen, and Makarov) is presented, demonstrating nutrient-like vertical profiles with 5-10 times higher concentrations in the intermediate and deep <span class="hlt">water</span> masses than in surface <span class="hlt">waters</span>. The consistent vertical profiles in all three Arctic <span class="hlt">Ocean</span> basins likely reflect buildup of PCBs transported from the shelf seas and from dissolution and/or mineralization of settling particles. Combined with measurement data on PCBs in other Arctic <span class="hlt">Ocean</span> compartments collected over the past decade, the total Arctic <span class="hlt">Ocean</span> inventory of ∑7PCB was estimated to 182 ± 40 t (±1 standard error of the mean), with sediments (144 ± 40 t), intermediate (5 ± 1 t) and deep <span class="hlt">water</span> masses (30 ± 2 t) storing 98% of the PCBs in the Arctic <span class="hlt">Ocean</span>. Further, we used hydrographic and carbon cycle parametrizations to assess the main pathways of PCBs into and out of the Arctic <span class="hlt">Ocean</span> during the 20th century. River discharge appeared to be the major pathway for PCBs into the Arctic <span class="hlt">Ocean</span> with 115 ± 11 t, followed by <span class="hlt">ocean</span> currents (52 ± 17 t) and net atmospheric deposition (30 ± 28 t). <span class="hlt">Ocean</span> currents provided the only important pathway out of the Arctic <span class="hlt">Ocean</span>, with an estimated cumulative flux of 22 ± 10 t. The observation-based inventory of ∑7PCB of 182 ± 40 t is consistent with the contemporary inventory based on cumulative fluxes for ∑7PCB of 173 ± 36 t. Information on the concentration and distribution of PCBs in the deeper compartments of the Arctic <span class="hlt">Ocean</span> improves our understanding of the large-scale fate of POPs in the Arctic and may also provide a means to test and improve models used to assess the fate of organic pollutants in the Arctic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2006DSRI...53.1517M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2006DSRI...53.1517M"><span>Ectoenzymatic activity in surface <span class="hlt">waters</span>: A transect from the Mediterranean Sea across the Indian <span class="hlt">Ocean</span> to Australia</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Misic, C.; Castellano, M.; Fabiano, M.; Ruggieri, N.; Saggiomo, V.; Povero, P.</p> <p>2006-09-01</p> <p>The activities of two hydrolytic enzymes (leucine aminopeptidase and β glucosidase), belonging to the particle-bound enzymatic fraction, were measured in <span class="hlt">open</span>-sea surface <span class="hlt">waters</span>. Samples were collected along a transect crossing the Indian <span class="hlt">Ocean</span> during the early NW monsoon period (November and December 2001). The latitudinal pattern of the ectoenzymatic activities highlighted a generally increasing trend of glycolysis approaching the equator, with significantly higher β glucosidase activity (0.79-3.00 nmol l -1 h -1) within the latitudinal range from 12°N to 16°S. In this area, the surface <span class="hlt">waters</span> coming from the Indonesian Throughflow and the Bay of Bengal carry a considerable quantity of carbohydrates (38.9-41.9 μg l -1), which stimulated glycolytic activity and its cell-specific rates scaled to bacterial abundance. On the other hand, in the Central Indian <span class="hlt">Ocean</span>, the proteolytic activity was considerable (0.91-2.03 nmol l -1 h -1), although the particulate proteins did not show significant increases and the dissolved proteinlike signal was one of the lowest of the entire transect (0.7 mg l -1 on average compared to the 1.4-1.6 mg l -1 of the adjacent areas). Therefore, in this area, the two ectoenzymes studied did not respond to the same stimulatory effect (namely the specific substrate concentrations). The time needed for the hydrolysis of macromolecules within the particulate and dissolved organic substrate fractions, although these measures are affected by a number of assumptions starting with the potential nature of the ectoenzymatic determinations, confirms these observations. The Central Indian <span class="hlt">Ocean</span> displayed the lowest values, from 8 to 26 days for particulate and dissolved organic carbon, respectively. As observed in the equatorial areas of the Atlantic <span class="hlt">Ocean</span>, the relevant degradation activity of the central area of the Indian <span class="hlt">Ocean</span> Basin suggests a notable heterotrophy based on a faster turnover of organic substrates.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27659188','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27659188"><span>Disparate acidification and calcium carbonate desaturation of deep and shallow <span class="hlt">waters</span> of the Arctic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Luo, Yiming; Boudreau, Bernard P; Mucci, Alfonso</p> <p>2016-09-23</p> <p>The Arctic <span class="hlt">Ocean</span> is acidifying from absorption of man-made CO2. Current predictive models of that acidification focus on surface <span class="hlt">waters</span>, and their results argue that deep <span class="hlt">waters</span> will acidify by downward penetration from the surface. Here we show, with an alternative model, the rapid, near simultaneous, acidification of both surface and deep <span class="hlt">waters</span>, a prediction supported by current, but limited, saturation data. Whereas Arctic surface <span class="hlt">water</span> responds directly by atmospheric CO2 uptake, deeper <span class="hlt">waters</span> will be influenced strongly by intrusion of mid-depth, pre-acidified, Atlantic <span class="hlt">Ocean</span> <span class="hlt">water</span>. With unabated CO2 emissions, surface <span class="hlt">waters</span> will become undersaturated with respect to aragonite by 2105 AD and could remain so for ∼600 years. In deep <span class="hlt">waters</span>, the aragonite saturation horizon will rise, reaching the base of the surface mixed layer by 2140 AD and likely remaining there for over a millennium. The survival of aragonite-secreting organisms is consequently threatened on long timescales.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatCo...712821L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatCo...712821L"><span>Disparate acidification and calcium carbonate desaturation of deep and shallow <span class="hlt">waters</span> of the Arctic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Luo, Yiming; Boudreau, Bernard P.; Mucci, Alfonso</p> <p>2016-09-01</p> <p>The Arctic <span class="hlt">Ocean</span> is acidifying from absorption of man-made CO2. Current predictive models of that acidification focus on surface <span class="hlt">waters</span>, and their results argue that deep <span class="hlt">waters</span> will acidify by downward penetration from the surface. Here we show, with an alternative model, the rapid, near simultaneous, acidification of both surface and deep <span class="hlt">waters</span>, a prediction supported by current, but limited, saturation data. Whereas Arctic surface <span class="hlt">water</span> responds directly by atmospheric CO2 uptake, deeper <span class="hlt">waters</span> will be influenced strongly by intrusion of mid-depth, pre-acidified, Atlantic <span class="hlt">Ocean</span> <span class="hlt">water</span>. With unabated CO2 emissions, surface <span class="hlt">waters</span> will become undersaturated with respect to aragonite by 2105 AD and could remain so for ~600 years. In deep <span class="hlt">waters</span>, the aragonite saturation horizon will rise, reaching the base of the surface mixed layer by 2140 AD and likely remaining there for over a millennium. The survival of aragonite-secreting organisms is consequently threatened on long timescales.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5036158','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5036158"><span>Disparate acidification and calcium carbonate desaturation of deep and shallow <span class="hlt">waters</span> of the Arctic <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Luo, Yiming; Boudreau, Bernard P.; Mucci, Alfonso</p> <p>2016-01-01</p> <p>The Arctic <span class="hlt">Ocean</span> is acidifying from absorption of man-made CO2. Current predictive models of that acidification focus on surface <span class="hlt">waters</span>, and their results argue that deep <span class="hlt">waters</span> will acidify by downward penetration from the surface. Here we show, with an alternative model, the rapid, near simultaneous, acidification of both surface and deep <span class="hlt">waters</span>, a prediction supported by current, but limited, saturation data. Whereas Arctic surface <span class="hlt">water</span> responds directly by atmospheric CO2 uptake, deeper <span class="hlt">waters</span> will be influenced strongly by intrusion of mid-depth, pre-acidified, Atlantic <span class="hlt">Ocean</span> <span class="hlt">water</span>. With unabated CO2 emissions, surface <span class="hlt">waters</span> will become undersaturated with respect to aragonite by 2105 AD and could remain so for ∼600 years. In deep <span class="hlt">waters</span>, the aragonite saturation horizon will rise, reaching the base of the surface mixed layer by 2140 AD and likely remaining there for over a millennium. The survival of aragonite-secreting organisms is consequently threatened on long timescales. PMID:27659188</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19601959','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19601959"><span>Ammonia-oxidizing Archaea in the Arctic <span class="hlt">Ocean</span> and Antarctic coastal <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kalanetra, Karen M; Bano, Nasreen; Hollibaugh, James T</p> <p>2009-09-01</p> <p>We compared abundance, distributions and phylogenetic composition of Crenarchaeota and ammonia-oxidizing Archaea (AOA) in samples collected from coastal <span class="hlt">waters</span> west of the Antarctic Peninsula during the summers of 2005 and 2006, with samples from the central Arctic <span class="hlt">Ocean</span> collected during the summer of 1997. Ammonia-oxidizing Archaea and Crenarchaeota abundances were estimated from quantitative PCR measurements of amoA and 16S rRNA gene abundances. Crenarchaeota and AOA were approximately fivefold more abundant at comparable depths in the Antarctic versus the Arctic <span class="hlt">Ocean</span>. Crenarchaeota and AOA were essentially absent from the Antarctic Summer Surface <span class="hlt">Water</span> (SSW) <span class="hlt">water</span> mass (0-45 m depth). The ratio of Crenarchaeota 16S rRNA to archaeal amoA gene abundance in the Winter <span class="hlt">Water</span> (WW) <span class="hlt">water</span> mass (45-105 m depth) of the Southern <span class="hlt">Ocean</span> was much lower (0.15) than expected and in sharp contrast to the ratio (2.0) in the Circumpolar Deep <span class="hlt">Water</span> (CDW) <span class="hlt">water</span> mass (105-3500 m depth) immediately below it. We did not observe comparable segregation of this ratio by depth or <span class="hlt">water</span> mass in Arctic <span class="hlt">Ocean</span> samples. A ubiquitous, abundant and polar-specific crenarchaeote was the dominant ribotype in the WW and important in the upper halocline of the Arctic <span class="hlt">Ocean</span>. Our data suggest that this organism does not contain an ammonia monooxygenase gene. In contrast to other studies where Crenarchaeota populations apparently lacking amoA genes are found in bathypelagic <span class="hlt">waters</span>, this organism appears to dominate in well-defined, ammonium-rich, near-surface <span class="hlt">water</span> masses in polar <span class="hlt">oceans</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23037125','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23037125"><span>Atmospheric correction of satellite <span class="hlt">ocean</span> color imagery using the ultraviolet wavelength for highly turbid <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>He, Xianqiang; Bai, Yan; Pan, Delu; Tang, Junwu; Wang, Difeng</p> <p>2012-08-27</p> <p>Instead of the conventionally atmospheric correction algorithms using the near-infrared and shortwave infrared wavelengths, an alternative practical atmospheric correction algorithm using the ultraviolet wavelength for turbid <span class="hlt">waters</span> (named UV-AC) is proposed for satellite <span class="hlt">ocean</span> color imagery in the paper. The principle of the algorithm is based on the fact that the <span class="hlt">water</span>-leaving radiance at ultraviolet wavelengths can be neglected as compared with that at the visible light wavelengths or even near-infrared wavelengths in most cases of highly turbid <span class="hlt">waters</span> due to the strong absorption by detritus and colored dissolved organic matter. The UV-AC algorithm uses the ultraviolet band to estimate the aerosol scattering radiance empirically, and it does not need any assumption of the <span class="hlt">water</span>'s optical properties. Validations by both of the simulated data and in situ data show that the algorithm is appropriate for the retrieval of the <span class="hlt">water</span>-leaving radiance in turbid <span class="hlt">waters</span>. The UV-AC algorithm can be used for all the current satellite <span class="hlt">ocean</span> color sensors, and it is especially useful for those <span class="hlt">ocean</span> color sensors lacking the shortwave infrared bands. Moreover, the algorithm can be used for any turbid <span class="hlt">waters</span> with negligible <span class="hlt">water</span>-leaving radiance at ultraviolet wavelength. Based on our work, we recommend the future satellite <span class="hlt">ocean</span> color remote sensors setting the ultraviolet band to perform the atmospheric correction in turbid <span class="hlt">waters</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014OcMod..82...28H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014OcMod..82...28H"><span>Eddy-resolving simulations of the Fimbul Ice Shelf cavity circulation: Basal melting and exchange with <span class="hlt">open</span> <span class="hlt">ocean</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hattermann, T.; Smedsrud, L. H.; Nøst, O. A.; Lilly, J. M.; Galton-Fenzi, B. K.</p> <p>2014-10-01</p> <p>Melting at the base of floating ice shelves is a dominant term in the overall Antarctic mass budget. This study applies a high-resolution regional ice shelf/<span class="hlt">ocean</span> model, constrained by observations, to (i) quantify present basal mass loss at the Fimbul Ice Shelf (FIS); and (ii) investigate the <span class="hlt">oceanic</span> mechanisms that govern the heat supply to ice shelves in the Eastern Weddell Sea. The simulations confirm the low melt rates suggested by observations and show that melting is primarily determined by the depth of the coastal thermocline, regulating deep <span class="hlt">ocean</span> heat fluxes towards the ice. Furthermore, the uneven distribution of ice shelf area at different depths modulates the melting response to <span class="hlt">oceanic</span> forcing, causing the existence of two distinct states of melting at the FIS. In the simulated present-day state, only small amounts of Modified Warm Deep <span class="hlt">Water</span> enter the continental shelf, and <span class="hlt">ocean</span> temperatures beneath the ice are close to the surface freezing point. The basal mass loss in this so-called state of “shallow melting” is mainly controlled by the seasonal inflow of solar-heated surface <span class="hlt">water</span> affecting large areas of shallow ice in the upper part of the cavity. This is in contrast to a state of “deep melting”, in which the thermocline rises above the shelf break depth, establishing a continuous inflow of Warm Deep <span class="hlt">Water</span> towards the deep ice. The transition between the two states is found to be determined by a complex response of the Antarctic Slope Front overturning circulation to varying climate forcings. A proper representation of these frontal dynamics in climate models will therefore be crucial when assessing the evolution of ice shelf basal melting along this sector of Antarctica.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7703L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7703L"><span>The European Fixed point <span class="hlt">Open</span> <span class="hlt">Ocean</span> Observatory network (FixO3): Multidisciplinary observations from the air-sea interface to the deep seafloor</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lampitt, Richard; Cristini, Luisa; Alexiou, Sofia</p> <p>2015-04-01</p> <p>The Fixed point <span class="hlt">Open</span> <span class="hlt">Ocean</span> Observatory network (FixO3, http://www.fixo3.eu/ ) integrates 23 European <span class="hlt">open</span> <span class="hlt">ocean</span> fixed point observatories and improves access to these infrastructures for the broader community. These provide multidisciplinary observations in all parts of the <span class="hlt">oceans</span> from the air-sea interface to the deep seafloor. Started in September 2013 with a budget of 7 Million Euros over 4 years, the project has 29 partners drawn from academia, research institutions and SME's coordinated by the National Oceanography Centre, UK. Here we present the programme's achievements in the 18 months and the activities of the 12 Work Packages which have the objectives to: • integrate and harmonise the current procedures and processes • offer free access to observatory infrastructures to those who do not have such access, and free and <span class="hlt">open</span> data services and products • innovate and enhance the current capability for multidisciplinary in situ <span class="hlt">ocean</span> observation <span class="hlt">Open</span> <span class="hlt">ocean</span> observation is a high priority for European marine and maritime activities. FixO3 provides important data and services to address the Marine Strategy Framework Directive and in support of the European Integrated Maritime Policy. FixO3 provides a strong integrated framework of <span class="hlt">open</span> <span class="hlt">ocean</span> facilities in the Atlantic from the Arctic to the Antarctic and throughout the Mediterranean, enabling an integrated, regional and multidisciplinary approach to understand natural and anthropogenic change in the <span class="hlt">ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15744299','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15744299"><span><span class="hlt">Water</span>-rich basalts at mid-<span class="hlt">ocean</span>-ridge cold spots.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ligi, Marco; Bonatti, Enrico; Cipriani, Anna; Ottolini, Luisa</p> <p>2005-03-03</p> <p>Although <span class="hlt">water</span> is only present in trace amounts in the suboceanic upper mantle, it is thought to play a significant role in affecting mantle viscosity, melting and the generation of crust at mid-<span class="hlt">ocean</span> ridges. The concentration of <span class="hlt">water</span> in <span class="hlt">oceanic</span> basalts has been observed to stay below 0.2 wt%, except for <span class="hlt">water</span>-rich basalts sampled near hotspots and generated by 'wet' mantle plumes. Here, however, we report unusually high <span class="hlt">water</span> content in basaltic glasses from a cold region of the mid-<span class="hlt">ocean</span>-ridge system in the equatorial Atlantic <span class="hlt">Ocean</span>. These basalts are sodium-rich, having been generated by low degrees of melting of the mantle, and contain unusually high ratios of light versus heavy rare-earth elements, implying the presence of garnet in the melting region. We infer that <span class="hlt">water</span>-rich basalts from such regions of thermal minima derive from low degrees of 'wet' melting greater than 60 km deep in the mantle, with minor dilution by melts produced by shallower 'dry' melting--a view supported by numerical modelling. We therefore conclude that <span class="hlt">oceanic</span> basalts are <span class="hlt">water</span>-rich not only near hotspots, but also at 'cold spots'.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28650623','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28650623"><span>Spatial Distributions of DDTs in the <span class="hlt">Water</span> Masses of the Arctic <span class="hlt">Ocean</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carrizo, Daniel; Sobek, Anna; Salvadó, Joan A; Gustafsson, Örjan</p> <p>2017-07-18</p> <p>There is a scarcity of data on the amount and distribution of the organochlorine pesticide dichlorodiphenyltrichloroethane (DDT) and its metabolites in intermediate and deep <span class="hlt">ocean</span> <span class="hlt">water</span> masses. Here, the distribution and inventories of DDTs in <span class="hlt">water</span> of the Arctic shelf seas and the interior basin are presented. The occurrence of ∑6DDT (0.10-66 pg L(-1)) in the surface <span class="hlt">water</span> was dominated by 4,4'-DDE. In the Central Arctic <span class="hlt">Ocean</span> increasing concentrations of DDE with depth were observed in the Makarov and Amundsen basins. The increasing concentrations down to 2500 m depth is in accordance with previous findings for PCBs and PBDEs. Similar concentrations of DDT and DDEs were found in the surface <span class="hlt">water</span>, while the relative contribution of DDEs increased with depth, demonstrating a transformation over time and depth. Higher concentrations of DDTs were found in the European part of the Arctic <span class="hlt">Ocean</span>; these distributions likely reflect a combination of different usage patterns, transport, and fate of these compounds. For instance, the elevated concentrations of DDTs in the Barents and Atlantic sectors of the Arctic <span class="hlt">Ocean</span> indicate the northbound Atlantic current as a significant conveyor of DDTs. This study contributes to the very rare data on OCPs in the vast deep-<span class="hlt">water</span> compartments and combined with surface <span class="hlt">water</span> distribution across the Arctic <span class="hlt">Ocean</span> helps to improve our understanding of the large-scale fate of DDTs in the Arctic.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JMEP...26.2337L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JMEP...26.2337L"><span>Slow Strain Rate Testing for Hydrogen Embrittlement Susceptibility of Alloy 718 in Substitute <span class="hlt">Ocean</span> <span class="hlt">Water</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>LaCoursiere, M. P.; Aidun, D. K.; Morrison, D. J.</p> <p>2017-05-01</p> <p>The hydrogen embrittlement susceptibility of near-peak-aged UNS N07718 (Alloy 718) was evaluated by performing slow strain rate tests at room temperature in air and substitute <span class="hlt">ocean</span> <span class="hlt">water</span>. Tests in substitute <span class="hlt">ocean</span> <span class="hlt">water</span> were accomplished in an environmental cell that enabled in situ cathodic charging under an applied potential of -1.1 V versus SCE. Some specimens were cathodically precharged for 4 or 16 weeks at the same potential in a 3.5 wt.% NaCl-distilled <span class="hlt">water</span> solution at 50 °C. Unprecharged specimens tested in substitute <span class="hlt">ocean</span> <span class="hlt">water</span> exhibited only moderate embrittlement with plastic strain to failure decreasing by about 20% compared to unprecharged specimens tested in air. However, precharged specimens exhibited significant embrittlement with plastic strain to failure decreasing by about 70%. Test environment (air or substitute <span class="hlt">ocean</span> <span class="hlt">water</span> with in situ charging) and precharge time (4 or 16 weeks) had little effect on the results of the precharged specimens. Fracture surfaces of precharged specimens were typical of hydrogen embrittlement and consisted of an outer brittle ring related to the region in which hydrogen infused during precharging, a finely dimpled transition zone probably related to the region where hydrogen was drawn in by dislocation transport, and a central highly dimpled ductile region. Fracture surfaces of unprecharged specimens tested in substitute <span class="hlt">ocean</span> <span class="hlt">water</span> consisted of a finely dimpled outer ring and heavily dimpled central region typical of ductile fracture.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.osti.gov/scitech/biblio/22348175','SCIGOV-STC'); return false;" href="https://www.osti.gov/scitech/biblio/22348175"><span><span class="hlt">Water</span> cycling between <span class="hlt">ocean</span> and mantle: Super-earths need not be waterworlds</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cowan, Nicolas B.; Abbot, Dorian S.</p> <p>2014-01-20</p> <p>Large terrestrial planets are expected to have muted topography and deep <span class="hlt">oceans</span>, implying that most super-Earths should be entirely covered in <span class="hlt">water</span>, so-called waterworlds. This is important because waterworlds lack a silicate weathering thermostat so their climate is predicted to be less stable than that of planets with exposed continents. In other words, the continuously habitable zone for waterworlds is much narrower than for Earth-like planets. A planet's <span class="hlt">water</span> is partitioned, however, between a surface reservoir, the <span class="hlt">ocean</span>, and an interior reservoir, the mantle. Plate tectonics transports <span class="hlt">water</span> between these reservoirs on geological timescales. Degassing of melt at mid-<span class="hlt">ocean</span> ridges and serpentinization of <span class="hlt">oceanic</span> crust depend negatively and positively on seafloor pressure, respectively, providing a stabilizing feedback on long-term <span class="hlt">ocean</span> volume. Motivated by Earth's approximately steady-state deep <span class="hlt">water</span> cycle, we develop a two-box model of the hydrosphere and derive steady-state solutions to the <span class="hlt">water</span> partitioning on terrestrial planets. Critically, hydrostatic seafloor pressure is proportional to surface gravity, so super-Earths with a deep <span class="hlt">water</span> cycle will tend to store more <span class="hlt">water</span> in the mantle. We conclude that a tectonically active terrestrial planet of any mass can maintain exposed continents if its <span class="hlt">water</span> mass fraction is less than ∼0.2%, dramatically increasing the odds that super-Earths are habitable. The greatest source of uncertainty in our study is Earth's current mantle <span class="hlt">water</span> inventory: the greater its value, the more robust planets are to inundation. Lastly, we discuss how future missions can test our hypothesis by mapping the <span class="hlt">oceans</span> and continents of massive terrestrial planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014ApJ...781...27C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014ApJ...781...27C"><span><span class="hlt">Water</span> Cycling between <span class="hlt">Ocean</span> and Mantle: Super-Earths Need Not Be Waterworlds</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cowan, Nicolas B.; Abbot, Dorian S.</p> <p>2014-01-01</p> <p>Large terrestrial planets are expected to have muted topography and deep <span class="hlt">oceans</span>, implying that most super-Earths should be entirely covered in <span class="hlt">water</span>, so-called waterworlds. This is important because waterworlds lack a silicate weathering thermostat so their climate is predicted to be less stable than that of planets with exposed continents. In other words, the continuously habitable zone for waterworlds is much narrower than for Earth-like planets. A planet's <span class="hlt">water</span> is partitioned, however, between a surface reservoir, the <span class="hlt">ocean</span>, and an interior reservoir, the mantle. Plate tectonics transports <span class="hlt">water</span> between these reservoirs on geological timescales. Degassing of melt at mid-<span class="hlt">ocean</span> ridges and serpentinization of <span class="hlt">oceanic</span> crust depend negatively and positively on seafloor pressure, respectively, providing a stabilizing feedback on long-term <span class="hlt">ocean</span> volume. Motivated by Earth's approximately steady-state deep <span class="hlt">water</span> cycle, we develop a two-box model of the hydrosphere and derive steady-state solutions to the <span class="hlt">water</span> partitioning on terrestrial planets. Critically, hydrostatic seafloor pressure is proportional to surface gravity, so super-Earths with a deep <span class="hlt">water</span> cycle will tend to store more <span class="hlt">water</span> in the mantle. We conclude that a tectonically active terrestrial planet of any mass can maintain exposed continents if its <span class="hlt">water</span> mass fraction is less than ~0.2%, dramatically increasing the odds that super-Earths are habitable. The greatest source of uncertainty in our study is Earth's current mantle <span class="hlt">water</span> inventory: the greater its value, the more robust planets are to inundation. Lastly, we discuss how future missions can test our hypothesis by mapping the <span class="hlt">oceans</span> and continents of massive terrestrial planets.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/16125769','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/16125769"><span>Discriminating zooplankton assemblages in neritic and <span class="hlt">oceanic</span> <span class="hlt">waters</span>: a case for the northeast coast of India, Bay of Bengal.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rakhesh, M; Raman, A V; Sudarsan, D</p> <p>2006-02-01</p> <p>Zooplankton species distribution and abundance data at 17 locations in the inshore (10-30 m), shelf (50-200 m) and <span class="hlt">oceanic</span> (2,500-2,800 m) regions off northeast India (Bay of Bengal) during January 1999-April 2001 revealed 112 taxa represented by 30 divergent groups. Copepods (58 species) dominated (87%) the population numerically. In general zooplankton diversity (Margalef richness d, Shannon-Wiener H', Pielou's evenness J') increased in the direction of the <span class="hlt">open</span> sea relative to coastal locations with a concomitant decrease both in abundance (ind m(-3)) and biomass (dry mass m(-3)). Based on multivariate analyses, it was possible to distinguish the zooplankton community into different assemblages according to their location (e.g., inshore, shelf, <span class="hlt">oceanic</span>) and seasonality. While Acrocalanus sp., Oithona sp., Corycaeus danae, Euterpina acutifrons, Paracalanus sp., and Acartia sp. were found characterizing the coastal locations, Oncaea venusta was the discriminating species for shelf <span class="hlt">waters</span>. In <span class="hlt">oceanic</span> areas, there was a clear dominance of Labidocera sp., Candacia sp., Euchaeta rimana, Centropages calaninus, Copilia mirabilis and Corycella gibbula. The investigations revealed that changes in zooplankton community structure across <span class="hlt">water</span> bodies could be associated with differing salinity. During November 1999 (post-monsoon), when salinity in the coastal <span class="hlt">waters</span> was relatively low (26-28.9 PSU), the zooplankton community consisted of mainly Acrocalanus sp., Salpa, Corycaeus danae, Oikopleura sp., Acartia sp., Evadne tergestina, and Creseis sp. In January 2000 (salinity 32.4-34.1), additionally Corycella gibbula, Labidocera sp., Centropages sp., Microsetella sp., Euterpina acutifrons, Canthocalanus pauper, and Oncaea venusta represented the population discriminating the assemblage from others. In May 2000 (pre-monsoon) when salinity was highest (34.7-35.3), Oithona sp., Paracalanus sp., and Acrocalanus gibber were found important. Chaetognaths formed a distinct group</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24251554','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24251554"><span>Organochlorine pesticides in the atmosphere and surface <span class="hlt">water</span> from the equatorial Indian <span class="hlt">Ocean</span>: enantiomeric signatures, sources, and fate.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Huang, Yumei; Xu, Yue; Li, Jun; Xu, Weihai; Zhang, Gan; Cheng, Zhineng; Liu, Junwen; Wang, Yan; Tian, Chongguo</p> <p>2013-01-01</p> <p>Nineteen pairs of gaseous and surface seawater samples were collected along the cruise from Malaysia to the south of Bay of Bengal passing by Sri Lanka between April 12 and May 4, 2011 on the Chinese research vessel Shiyan I to investigate the latest OCP pollution status over the equatorial Indian <span class="hlt">Ocean</span>. Significant decrease of α-HCH and γ-HCH was found in the air and dissolved <span class="hlt">water</span> phase owing to global restriction for decades. Substantially high levels of p,p'-DDT, o,p'-DDT, trans-chlordane (TC), and cis-chlordane (CC) were observed in the <span class="hlt">water</span> samples collected near Sri Lanka, indicating fresh continental riverine input of these compounds. Fugacity fractions suggest equilibrium of α-HCH at most sampling sites, while net volatilization for DDT isomers, TC and CC in most cases. Enantiomer fractions (EFs) of α-HCH and o,p'-DDT in the air and <span class="hlt">water</span> samples were determined to trace the source of these compounds in the air. Racemic or close to racemic composition was found for atmospheric α-HCH and o,p'-DDT, while significant depletion of (+) enantiomer was found in the <span class="hlt">water</span> phase, especially for o,p'-DDT (EFs = 0.310 ± 0.178). 24% of α-HCH in the lower air over the <span class="hlt">open</span> sea of the equatorial Indian <span class="hlt">Ocean</span> is estimated to be volatilized from local seawater, indicating that long-range transport is the main source.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017JGRC..122.4587S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017JGRC..122.4587S"><span><span class="hlt">Open-ocean</span> convection process: A driver of the winter nutrient supply and the spring phytoplankton distribution in the Northwestern Mediterranean Sea</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Severin, Tatiana; Kessouri, Faycal; Rembauville, Mathieu; Sánchez-Pérez, Elvia Denisse; Oriol, Louise; Caparros, Jocelyne; Pujo-Pay, Mireille; Ghiglione, Jean-François; D'Ortenzio, Fabrizio; Taillandier, Vincent; Mayot, Nicolas; Durrieu De Madron, Xavier; Ulses, Caroline; Estournel, Claude; Conan, Pascal</p> <p>2017-06-01</p> <p>This study was a part of the DeWEX project (Deep <span class="hlt">Water</span> formation Experiment), designed to better understand the impact of dense <span class="hlt">water</span> formation on the marine biogeochemical cycles. Here, nutrient and phytoplankton vertical and horizontal distributions were investigated during a deep <span class="hlt">open-ocean</span> convection event and during the following spring bloom in the Northwestern Mediterranean Sea (NWM). In February 2013, the deep convection event established a surface nutrient gradient from the center of the deep convection patch to the surrounding mixed and stratified areas. In the center of the convection area, a slight but significant difference of nitrate, phosphate and silicate concentrations was observed possibly due to the different volume of deep <span class="hlt">waters</span> included in the mixing or to the sediment resuspension occurring where the mixing reached the bottom. One of this process, or a combination of both, enriched the <span class="hlt">water</span> column in silicate and phosphate, and altered significantly the stoichiometry in the center of the deep convection area. This alteration favored the local development of microphytoplankton in spring, while nanophytoplankton dominated neighboring locations where the convection reached the deep layer but not the bottom. This study shows that the convection process influences both winter nutrients distribution and spring phytoplankton distribution and community structure. Modifications of the convection's spatial scale and intensity (i.e., convective mixing depth) are likely to have strong consequences on phytoplankton community structure and distribution in the NWM, and thus on the marine food web.<abstract type="synopsis"><title type="main">Plain Language SummaryThe deep <span class="hlt">open-ocean</span> convection in the Northwestern Mediterranean Sea is an important process for the formation and the circulation of the deep <span class="hlt">waters</span> of the entire Mediterranean Sea, but also for the local spring phytoplankton bloom. In this study, we showed that variations of the convective mixing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSIS54A2367L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSIS54A2367L"><span>Rapid instrument prototyping with <span class="hlt">open</span> source hardware and software: Application to <span class="hlt">water</span> quality in hypersaline estuaries.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Loose, B.; O'Shea, R.</p> <p>2016-02-01</p> <p>We describe the design and deployment of a <span class="hlt">water</span> quality sonde that utilizes mobile phone networks for near-real time data telemetry. The REOL or Realtime Estuary <span class="hlt">Ocean</span> Logger has the unique and valuable capability of logging data internally and simultaneously relaying the information to a webserver using a cellular modem. The internal circuitry consists of a GSM cellular modem, a microcontroller, and an SD card for data storage - these components are low cost, and backed up with circuit diagrams and programming libraries that are published under <span class="hlt">open</span> source license. This configuration is versatile and is capable of reading instrument output from a broad spectrum of devices, including serial, TTL, analog voltage (0 - 5V), and analog current (typically 4-20 mA). We find the greatest challenges lie in development of smart software that is capable of handling the conditions brought on by this harsh environment. We have programmed the sonde to first determine whether it is submerged by <span class="hlt">water</span>, and record the temperature on the electronics before deciding whether to telemeter measurements over the cellular network. The Google App EngineTM provides an interactive visualization platform. We have tested the REOL with a variety of <span class="hlt">water</span> quality sensors. In the configuration described here, we use a thermistor, depth gauge and torroidal conductivity sensor to measure <span class="hlt">water</span> temperature, <span class="hlt">water</span> level and conductivity up to 200 mS/cm. The latter is necessary for studies in hypersaline estuaries, where porewater salinity can exceed 100 g/kg. We present data from two estuaries in West Africa and from a longer-term deployment in the Narragansett Bay, Rhode Island.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/28911563','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/28911563"><span>Effects of electrode gap and electric potential on chlorine generation of electrolyzed deep <span class="hlt">ocean</span> <span class="hlt">water</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hsu, Guoo-Shyng Wang; Hsu, Shun-Yao</p> <p>2016-07-01</p> <p>Electrolyzed <span class="hlt">water</span> is a sustainable disinfectant, which can comply with food safety regulations and is environmentally friendly. A two-factor central composite design was adopted for studying the effects of electrode gap and electric potential on chlorine generation efficiency of electrolyzed deep <span class="hlt">ocean</span> <span class="hlt">water</span>. Deep <span class="hlt">ocean</span> <span class="hlt">water</span> was electrolyzed in a glass electrolyzing cell equipped with platinum-plated titanium anode and cathode. Results showed high electric efficiency at a low cell potential, and a high current density and high chlorine concentration at a high cell potential and low electrode gap. Current efficiency of the system was not significantly affected by electrode gap and electric potential. A small electrode gap reduced the required cell potential and resulted in high energy efficiency. The optimal choice of electrode gap and cell potential depends on the chlorine level of the electrolyzed deep <span class="hlt">ocean</span> <span class="hlt">water</span> to be produced, and a small electrode gap is preferred. Copyright © 2016. Published by Elsevier B.V.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://pubs.usgs.gov/of/2007/1047/srp/srp024/of2007-1047srp024.pdf','USGSPUBS'); return false;" href="https://pubs.usgs.gov/of/2007/1047/srp/srp024/of2007-1047srp024.pdf"><span>Abrupt turnover in calcareous-nannoplankton assemblages across the Paleocene/Eocene Thermal Maximum: implications for surface-<span class="hlt">water</span> oligotrophy over the Kerguelen Plateau, Southern Indian <span class="hlt">Ocean</span></span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Jiang, Shijun; Wise, Sherwood W.</p> <p>2007-01-01</p> <p><span class="hlt">Ocean</span> Drilling Program (ODP) Core Section 183-1135A-25R-4 from the Kerguelen Plateau in the Indian <span class="hlt">Ocean</span> sector of the Southern <span class="hlt">Ocean</span> represents only the second complete, expanded sequence through the Paleocene/Eocene Thermal Maximum (PETM; ~55 Ma) recovered from Antarctic <span class="hlt">waters</span>. Calcareous nannoplankton at this site underwent an abrupt, fundamental turnover across the PETM as defined by a carbon isotope excursion. Although Chiasmolithus, Discoaster, and Fasciculithus exponentially increase in abundance at the onset, the former abruptly drops but then rapidly recovers, whereas the latter two taxa show opposite trends due to surface-<span class="hlt">water</span> oligotrophy. These observations confirm previous results from ODP Site 690 on Maud Rise. The elevated pCO2 that accompanied the PETM caused a shoaling of the lysocline and carbonate compensation depth, leading to intensive dissolution of susceptible holococcoliths and poor preservation of the assemblages. Similarities and contrasts between the results of this study and previous work from <span class="hlt">open-ocean</span> sites and shelf margins further demonstrate that the response to the PETM was consistent in <span class="hlt">open-ocean</span> environments, but could be localized on continental shelves where nutrient regimes depend on the local geologic setting and oceanographic conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.dtic.mil/docs/citations/ADA575094','DTIC-ST'); return false;" href="http://www.dtic.mil/docs/citations/ADA575094"><span><span class="hlt">Ocean</span> Ambient Noise Studies for Shallow and Deep <span class="hlt">Water</span> Environments</span></a></p> <p><a target="_blank" href="http://www.dtic.mil/">DTIC Science & Technology</a></p> <p></p> <p>2012-09-30</p> <p>full wave <span class="hlt">ocean</span> noise model OASN [Schmidt 2004]. OASN is part of the OASES acoustic propagation package that numerically implements a full wave...solution producing a CSDM for surface noise in a horizontally stratified media using a spectral integration technique [Kuperman 1980, Jensen 2011]. OASES ...2004] H. Schmidt, OASES Version 3.1 User Guide and Reference Manual, Massachusetts Institute of Technology, http://acoustics.mit.edu/faculty/henrik</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=307077&keyword=logistic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=307077&keyword=logistic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50"><span>A Method to Identify Estuarine <span class="hlt">Water</span> Quality Exceedances Associated with <span class="hlt">Ocean</span> Conditions</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Wind driven coastal upwelling along the Pacific Northwest Coast of the US results in <span class="hlt">oceanic</span> <span class="hlt">water</span> that may be periodically entrained into adjacent estuaries and which possess high nutrients and low dissolved oxygen (DO). Measurement of <span class="hlt">water</span> quality indicators during these upwe...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=307077&keyword=national+AND+oceanic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78720397&CFTOKEN=88352984','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=307077&keyword=national+AND+oceanic&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=78720397&CFTOKEN=88352984"><span>A Method to Identify Estuarine <span class="hlt">Water</span> Quality Exceedances Associated with <span class="hlt">Ocean</span> Conditions</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>Wind driven coastal upwelling along the Pacific Northwest Coast of the US results in <span class="hlt">oceanic</span> <span class="hlt">water</span> that may be periodically entrained into adjacent estuaries and which possess high nutrients and low dissolved oxygen (DO). Measurement of <span class="hlt">water</span> quality indicators during these upwe...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1343334','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1343334"><span><span class="hlt">Open</span> <span class="hlt">water</span> scuba diving accidents at Leicester: five years' experience.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hart, A J; White, S A; Conboy, P J; Bodiwala, G; Quinton, D</p> <p>1999-01-01</p> <p>OBJECTIVES: The aim of this study was to determine the incidence, type, outcome, and possible risk factors of diving accidents in each year of a five year period presenting from one dive centre to a large teaching hospital accident and emergency (A&E) department. METHODS: All patients included in this study presented to the A&E department at a local teaching hospital in close proximity to the largest inland diving centre in the UK. Our main outcome measures were: presenting symptoms, administration of recompression treatment, mortality, and postmortem examination report where applicable. RESULTS: Overall, 25 patients experienced a serious <span class="hlt">open</span> <span class="hlt">water</span> diving accident at the centre between 1992 and 1996 inclusive. The percentage of survivors (n = 18) with symptoms of decompression sickness receiving recompression treatment was 52%. All surviving patients received medical treatment for at least 24 hours before discharge. The median depth of diving accidents was 24 metres (m) (range 7-36 m). During the study period, 1992-96, the number of accidents increased from one to 10 and the incidence of diving accidents increased from four per 100,000 to 15.4 per 100,000. Over the same time period the number of deaths increased threefold. CONCLUSIONS: The aetiology of the increase in the incidence of accidents is multifactorial. Important risk factors were thought to be: rapid ascent (in 48% of patients), cold <span class="hlt">water</span>, poor visibility, the number of dives per diver, and the experience of the diver. It is concluded that there needs to be an increased awareness of the management of diving injuries in an A&E department in close proximity to an inland diving centre. PMID:10353047</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017NPGeo..24..237B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017NPGeo..24..237B"><span><span class="hlt">Ocean</span> swell within the kinetic equation for <span class="hlt">water</span> waves</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Badulin, Sergei I.; Zakharov, Vladimir E.</p> <p>2017-06-01</p> <p>Results of extensive simulations of swell evolution within the duration-limited setup for the kinetic Hasselmann equation for long durations of up to 2 × 106 s are presented. Basic solutions of the theory of weak turbulence, the so-called Kolmogorov-Zakharov solutions, are shown to be relevant to the results of the simulations. Features of self-similarity of wave spectra are detailed and their impact on methods of <span class="hlt">ocean</span> swell monitoring is discussed. Essential drop in wave energy (wave height) due to wave-wave interactions is found at the initial stages of swell evolution (on the order of 1000 km for typical parameters of the <span class="hlt">ocean</span> swell). At longer times, wave-wave interactions are responsible for a universal angular distribution of wave spectra in a wide range of initial conditions. Weak power-law attenuation of swell within the Hasselmann equation is not consistent with results of <span class="hlt">ocean</span> swell tracking from satellite altimetry and SAR (synthetic aperture radar) data. At the same time, the relatively fast weakening of wave-wave interactions makes the swell evolution sensitive to other effects. In particular, as shown, coupling with locally generated wind waves can force the swell to grow in relatively light winds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ESASP.740E..58G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ESASP.740E..58G"><span>Dazzled by Ice and Snow: Improving Medium Spatial Resolution <span class="hlt">Ocean</span> Color Images in Arctic <span class="hlt">Waters</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Goyens, Clemence; Belanger, Simon; Babin, Marcel</p> <p>2016-08-01</p> <p><span class="hlt">Ocean</span> color sensors carried on-board satellites represent a valuable tool providing synoptic views of extreme environments such as the Arctic <span class="hlt">Ocean</span>. However, in icy <span class="hlt">waters</span> inaccuracies are frequent due to, among others, adjacent and sub-pixel sea-ice contamination. Therefore, there is a need to improve atmospheric correction (AC) algorithms to ensure accurate <span class="hlt">ocean</span> color images in the vicinity of the ice edge. The present study compares the performance of different AC methods through an in-situ-satellite match-up exercise and investigates the possibility to improve these algorithms in presence of sea-ice floes. Results confirm the large errors resulting from sea-ice contamination and illustrate the difficulty in improving these algorithms due to, among others, the optically complex <span class="hlt">waters</span> encountered in the Arctic <span class="hlt">Ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/18793309','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/18793309"><span>Diversity of deep-<span class="hlt">water</span> cetaceans in relation to temperature: implications for <span class="hlt">ocean</span> warming.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Whitehead, Hal; McGill, Brian; Worm, Boris</p> <p>2008-11-01</p> <p>Understanding the effects of natural environmental variation on biodiversity can help predict response to future anthropogenic change. Here we analyse a large, long-term data set of sightings of deep-<span class="hlt">water</span> cetaceans from the Atlantic, Pacific and Indian <span class="hlt">Oceans</span>. Seasonal and geographic changes in the diversity of these genera are well predicted by a convex function of sea-surface temperature peaking at c. 21 degrees C. Thus, diversity is highest at intermediate latitudes - an emerging general pattern for the pelagic <span class="hlt">ocean</span>. When applied to a range of Intergovernmental Panel on Climate Change global change scenarios, the predicted response is a decline of cetacean diversity across the tropics and increases at higher latitudes. This suggests that deep-<span class="hlt">water</span> <span class="hlt">oceanic</span> communities that dominate > 60% of the planet's surface may reorganize in response to <span class="hlt">ocean</span> warming, with low-latitude losses of diversity and resilience.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1990JCli....3..634S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1990JCli....3..634S"><span>On the Relationship between <span class="hlt">Water</span> Vapor over the <span class="hlt">Oceans</span> and Sea Surface Temperature.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Stephens, Graeme L.</p> <p>1990-06-01</p> <p>Monthly mean precipitable <span class="hlt">water</span> data obtained from passive microwave radiometry (SMMR) are correlated with NMC-blended sea surface temperature data. It is shown that the monthly mean <span class="hlt">water</span> vapor content of the atmosphere above the <span class="hlt">oceans</span> can generally be prescribed from the sea surface temperature with a standard deviation of O.36 g cm2. The form of the relationship between precipitable <span class="hlt">water</span> and sea surface temperature in the range Ts gt; 15°C also resembles that predicted from simple arguments based on the Clausius-Clapeyron relationship. The annual cycle of the mass of SMMR <span class="hlt">water</span> vapor integrated over the global <span class="hlt">oceans</span> is shown to differ from analyses of fully global <span class="hlt">water</span> vapor data in both phase and amplitude, and these difference paint to a significant influence of the continents on <span class="hlt">water</span> vapor. Regional scale analyses of <span class="hlt">water</span> vapor demonstrate that monthly averaged <span class="hlt">water</span> vapor data, when contrasted with the bulk sea surface temperature relationship developed in this study, reflect various known characteristics of the time mean large-scale circulation over the <span class="hlt">oceans</span>. A <span class="hlt">water</span> vapor parameter is introduced to highlight the effects of large-scale motion on atmospheric <span class="hlt">water</span> vapor. Based on the magnitude of this parameter, it is shown that the effects of large-scale flow on precipitable <span class="hlt">water</span> vapor are regionally dependent, but for the most part, the influence of circulation is generally less than about ±20% of the seasonal mean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23948091','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23948091"><span>Towards environmental management of <span class="hlt">water</span> turbidity within <span class="hlt">open</span> coastal <span class="hlt">waters</span> of the Great Barrier Reef.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Macdonald, Rachael K; Ridd, Peter V; Whinney, James C; Larcombe, Piers; Neil, David T</p> <p>2013-09-15</p> <p><span class="hlt">Water</span> turbidity and suspended sediment concentration (SSC) are commonly used as part of marine monitoring and <span class="hlt">water</span> quality plans. Current management plans utilise threshold SSC values derived from mean-annual turbidity concentrations. Little published work documents typical ranges of turbidity for reefs within <span class="hlt">open</span> coastal <span class="hlt">waters</span>. Here, time-series turbidity measurements from 61 sites in the Great Barrier Reef (GBR) and Moreton Bay, Australia, are presented as turbidity exceedance curves and derivatives. This contributes to the understanding of turbidity and SSC in the context of environmental management in <span class="hlt">open</span>-coastal reef environments. Exceedance results indicate strong spatial and temporal variability in <span class="hlt">water</span> turbidity across inter/intraregional scales. The highest turbidity across 61 sites, at 50% exceedance (T50) is 15.3 NTU and at 90% exceedance (T90) 4.1 NTU. Mean/median turbidity comparisons show strong differences between the two, consistent with a strongly skewed turbidity regime. Results may contribute towards promoting refinement of <span class="hlt">water</span> quality management protocols.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27054351','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27054351"><span>Training for a 78-km solo <span class="hlt">open</span> <span class="hlt">water</span> swim.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Piacentini, Maria F; DE Ioannon, Giulia; Cibelli, Giuseppe; Mignardi, Sergio; Antonelli, Agnese; Capranica, Laura</p> <p>2017-06-01</p> <p>The purpose of the present study was to report the training of a master athlete in preparation to an ultra-marathon swimming event. For 32 weeks prior to a 78-km "solo" <span class="hlt">open</span> <span class="hlt">water</span> swim from Italy to Albania, a male long distance master (48 years) swimmer was monitored. Training volume was recorded as total time and distance while intensities were recorded according to international classifications utilizing the primary goal of the session method. Thereafter, time spent in the three training zones: Z1 (low intensity training), Z2 (threshold training) and Z3 (high intensity training) was calculated. Weekly swimming volume ranged from 15 to 70 km.week-1 and training frequency ranged from 3 to 6 days.week-1. Total weekly training dedicated to swimming ranged from 270 to 1140 min. Training intensity comprised Z1=64%. Z2=28%, and Z3=8%, respectively. During the three-week taper period, total swimming volume decreased by 43% while intensity remained unchanged. The athlete succeeded in being the first swimmer to accomplish the event. These findings provide useful information for coaches on training regimens of master ultra-marathon swimmers. Compared to the literature, time spent at a Z1 training intensity was lower in favor of that spent in Z2. It could be speculated that master ultra-marathon athletes might benefit from training intensities at or above LT to counterbalance the age-related physiological decrease.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoRL..41.3649B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoRL..41.3649B"><span>High abundances of oxalic, azelaic, and glyoxylic acids and methylglyoxal in the <span class="hlt">open</span> <span class="hlt">ocean</span> with high biological activity: Implication for secondary OA formation from isoprene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Bikkina, Srinivas; Kawamura, Kimitaka; Miyazaki, Yuzo; Fu, Pingqing</p> <p>2014-05-01</p> <p>Atmospheric dicarboxylic acids (DCA) are a ubiquitous <span class="hlt">water</span>-soluble component of secondary organic aerosols (SOA), which can act as cloud condensation nuclei (CCN), affecting the Earth's climate. Despite the high abundances of oxalic acid and related compounds in the marine aerosols, there is no consensus on what controls their distributions over the <span class="hlt">open</span> <span class="hlt">ocean</span>. Marine biological productivity could play a role in the production of DCA, but there is no substantial evidence to support this hypothesis. Here we present latitudinal distributions of DCA, oxoacids and α-dicarbonyls in the marine aerosols from the remote Pacific. Their concentrations were found several times higher in more biologically influenced aerosols (MBA) than less biologically influenced aerosols. We propose isoprene and unsaturated fatty acids as sources of DCA as inferred from significantly higher abundances of isoprene-SOA tracers and azelaic acid in MBA. These results have implications toward the reassessment of climate forcing feedbacks of marine-derived SOA.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17616872','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17616872"><span>Contamination of tap <span class="hlt">water</span> on an <span class="hlt">ocean</span>-going vessel.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Meyer, Gabriele; Neubauer, Birger; Schepers, Bernd-Fred</p> <p>2007-04-01</p> <p>The crew of a container vessel detected an aromatic odor of the tap <span class="hlt">water</span> that was produced on board. As the origin of the contamination was not obvious, <span class="hlt">water</span> was taken at different sampling sites of the <span class="hlt">water</span> supply of the vessel. Samples were analyzed for occurrence of chemical substances by GC-MS. Thereby xylene and ethylbenzene were detected in nearly each sample. The highest xylene concentration was found in the sample from the fresh <span class="hlt">water</span> tank. As xylene was used as solvent in the tank coating, it could be concluded that it was released by the coating. Consequently, the crew was advised to ventilate and clean the fresh <span class="hlt">water</span> tanks.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70024918','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70024918"><span>Interaction of sea <span class="hlt">water</span> and lava during submarine eruptions at mid-<span class="hlt">ocean</span> ridges</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Perfit, M.R.; Cann, J.R.; Fornari, D.J.; Engels, J.; Smith, D.K.; Ridley, W.I.; Edwards, M.H.</p> <p>2003-01-01</p> <p>Lava erupts into cold sea <span class="hlt">water</span> on the <span class="hlt">ocean</span> floor at mid-<span class="hlt">ocean</span> ridges (at depths of 2,500 m and greater), and the resulting flows make up the upper part of the global <span class="hlt">oceanic</span> crust. Interactions between heated sea <span class="hlt">water</span> and molten basaltic lava could exert significant control on the dynamics of lava flows and on their chemistry. But it has been thought that heating sea <span class="hlt">water</span> at pressures of several hundred bars cannot produce significant amounts of vapour and that a thick crust of chilled glass on the exterior of lava flows minimizes the interaction of lava with sea <span class="hlt">water</span>. Here we present evidence to the contrary, and show that bubbles of vaporized sea <span class="hlt">water</span> often rise through the base of lava flows and collect beneath the chilled upper crust. These bubbles of steam at magmatic temperatures may interact both chemically and physically with flowing lava, which could influence our understanding of deep-sea volcanic processes and <span class="hlt">oceanic</span> crustal construction more generally. We infer that vapour formation plays an important role in creating the collapse features that characterize much of the upper <span class="hlt">oceanic</span> crust and may accordingly contribute to the measured low seismic velocities in this layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/14603316','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/14603316"><span>Interaction of sea <span class="hlt">water</span> and lava during submarine eruptions at mid-<span class="hlt">ocean</span> ridges.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Perfit, Michael R; Cann, Johnson R; Fornari, Daniel J; Engels, Jennifer; Smith, Deborah K; Ridley, W Ian; Edwards, Margo H</p> <p>2003-11-06</p> <p>Lava erupts into cold sea <span class="hlt">water</span> on the <span class="hlt">ocean</span> floor at mid-<span class="hlt">ocean</span> ridges (at depths of 2,500 m and greater), and the resulting flows make up the upper part of the global <span class="hlt">oceanic</span> crust. Interactions between heated sea <span class="hlt">water</span> and molten basaltic lava could exert significant control on the dynamics of lava flows and on their chemistry. But it has been thought that heating sea <span class="hlt">water</span> at pressures of several hundred bars cannot produce significant amounts of vapour and that a thick crust of chilled glass on the exterior of lava flows minimizes the interaction of lava with sea <span class="hlt">water</span>. Here we present evidence to the contrary, and show that bubbles of vaporized sea <span class="hlt">water</span> often rise through the base of lava flows and collect beneath the chilled upper crust. These bubbles of steam at magmatic temperatures may interact both chemically and physically with flowing lava, which could influence our understanding of deep-sea volcanic processes and <span class="hlt">oceanic</span> crustal construction more generally. We infer that vapour formation plays an important role in creating the collapse features that characterize much of the upper <span class="hlt">oceanic</span> crust and may accordingly contribute to the measured low seismic velocities in this layer.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016APS..DFDH13009W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016APS..DFDH13009W"><span>Dimensions of continents and <span class="hlt">oceans</span> - <span class="hlt">water</span> has carved a perfect cistern</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Whitehead, John A.</p> <p>2016-11-01</p> <p>The <span class="hlt">ocean</span> basins have almost exactly the correct surface area and average depth to hold Earth's <span class="hlt">water</span>. Two processes are responsible for this. First, Earth's continental crust is thinned by erosion so that average elevation is a few hundred meters above sea level. Second, the crust is thickened by lateral compression from mountain formation and sediments and <span class="hlt">water</span> lost in subduction is resupplied at least in part by voclanics. The resulting continents are approximately tabular in cross section, resulting in the well-known double hypsometric curve for Earth's elevation. Therefore, erosion and mountain building have enabled <span class="hlt">water</span> to carve its own cistern in the form of all the <span class="hlt">ocean</span> basins. A theoretical fluid model, suggested partly by laboratory experiments, produces such a tabular continent with a surface above sea level. A simple hydrostatic balance gives a first approximation for the average depth and area of <span class="hlt">oceans</span> and continents for present Earth as a function of material volumes and densities. Using a wide range of possible crust volumes with the present <span class="hlt">water</span> volume, the average continental crust thickness exceeds 22 km and <span class="hlt">ocean</span> area exceeds 25% of the globe. Other volumes of <span class="hlt">water</span> produce a wide range of areas and depths of <span class="hlt">oceans</span> and crust.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AGUOSPO14F2871T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AGUOSPO14F2871T"><span>Lagrangian pathways of deep <span class="hlt">water</span> upwelling in the Southern <span class="hlt">Ocean</span> State Estimate</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tamsitt, V. M.; Talley, L. D.; Mazloff, M. R.; Wang, J.</p> <p>2016-02-01</p> <p>Pathways of upwelling of deep <span class="hlt">waters</span> in the Southern <span class="hlt">Ocean</span> are investigated using Lagrangian particle trajectories advected offline in the 1/6th°, data-assimilating Southern <span class="hlt">Ocean</span> State Estimate (sose.ucsd.edu). A total of 18 million particles released at 1000 m - 3500 m at 30° S in each basin were tracked for 60 years by looping velocities from the latest 2005-2010 SOSE iteration. 5% of particles upwelled to 500 m or shallower by the end of the simulation with 37%, 42% and 21% from the Atlantic, Indian and Pacific basins, respectively. Trajectories indicate that particles in the neutral density range 26.7-28.1 from all basins enter the Antarctic Circumpolar Current (ACC), follow the fronts of the ACC, and tend to upwell to the surface <span class="hlt">ocean</span> toward the southern edge of the ACC and south of the ACC. We analyze differences in upwelling pathways between North Atlantic Deep <span class="hlt">Water</span> and Indian and Pacific deep <span class="hlt">waters</span> and explore the role of topography in the upwelling of these deep <span class="hlt">water</span> masses. These upwelling pathways are important to understanding the 3-dimensional structure of the Southern <span class="hlt">Ocean</span> overturning circulation and the supply of carbon and nutrient-rich <span class="hlt">waters</span> to the surface of the Southern <span class="hlt">Ocean</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24461428','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24461428"><span>Concentrations of mercury in tissues of striped dolphins suggest decline of pollution in Mediterranean <span class="hlt">open</span> <span class="hlt">waters</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Borrell, A; Aguilar, A; Tornero, V; Drago, M</p> <p>2014-07-01</p> <p>The Mediterranean is a semi-enclosed sea subject to high mercury (Hg) pollution from both natural and anthropogenic sources. With the objective of discerning temporal changes in marine Hg pollution in the <span class="hlt">oceanic</span> <span class="hlt">waters</span> of the northwestern Mediterranean Sea, we analysed liver and kidney from striped dolphins (Stenella coeruleoalba) collected during 2007-2009 and compared them with previous results from a similar sample from 1990-1993. The effect of body length and sex on tissue Hg concentrations was investigated to ensure an unbiased comparison between the periods. The Hg concentrations did not show significant sex-related differences in any tissue or period but were correlated positively with body length. Using body length as a covariate, Hg concentrations in liver and kidney were higher in 1990-1993 than in 2007-2009. This result suggests that measures to reduce emissions in Western European countries have been effective in reducing mercury pollution in Mediterranean <span class="hlt">open</span> <span class="hlt">waters</span>. Copyright © 2014 Elsevier Ltd. All rights reserved.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013Tecto..32.1343R','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013Tecto..32.1343R"><span>Mode of <span class="hlt">opening</span> of an <span class="hlt">oceanic</span> pull-apart: The 20°N Basin along the Owen Fracture Zone (NW Indian <span class="hlt">Ocean</span>)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Rodriguez, Mathieu; Chamot-Rooke, Nicolas; Fournier, Marc; Huchon, Philippe; Delescluse, Matthias</p> <p>2013-09-01</p> <p>basins are common features observed at releasing bends along major strike-slip faults. The formation and structural evolution of such basins have mostly been investigated in the continental domain and by sandbox laboratory experiments or numerical models. Here we present recently acquired multibeam bathymetry, 3.5 kHz echo sounder, and seismic profiles across the 20°N pull-apart Basin along the India-Arabia transform boundary, known as the Owen Fracture Zone (OFZ). Using nearby <span class="hlt">oceanic</span> drilling (Deep Sea Drilling Project 222), we constrain the structural evolution of the basin since <span class="hlt">opening</span> some 3 Myr ago. The 20°N Basin is large (90 km long and 35 km wide) despite limited transcurrent motion (~10 km). The first stage involved the formation of a step over along the OFZ and the subsequent isolation of a subsiding half graben. Extension and subsidence were further partitioned over three distinct subbasins separated by complex sets of transverse faults. The size of the basin was enhanced by gravity-driven collapse. The 20°N Basin has been a catchment for Indus turbidites since its <span class="hlt">opening</span>, which provide a good record of syn-sedimentary deformation. The deformation related to the subsidence of the half graben mimics rollover structures commonly encountered in salt tectonics, suggesting that subsidence was accommodated by one or several décollement layers at depth. Despite a different rheological context, the subsurface structure of the nascent <span class="hlt">oceanic</span> 20°N Basin is very similar to the more mature continental Dead Sea Basin along the Levant Fault, which also displays subbasins separated by transverse faults.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2017PalOc..32..674H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2017PalOc..32..674H"><span>Antarctic climate, Southern <span class="hlt">Ocean</span> circulation patterns, and deep <span class="hlt">water</span> formation during the Eocene</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Huck, Claire E.; van de Flierdt, Tina; Bohaty, Steven M.; Hammond, Samantha J.</p> <p>2017-07-01</p> <p>We assess early-to-middle Eocene seawater neodymium (Nd) isotope records from seven Southern <span class="hlt">Ocean</span> deep-sea drill sites to evaluate the role of Southern <span class="hlt">Ocean</span> circulation in long-term Cenozoic climate change. Our study sites are strategically located on either side of the Tasman Gateway and are positioned at a range of shallow (<500 m) to intermediate/deep ( 1000-2500 m) paleowater depths. Unradiogenic seawater Nd isotopic compositions, reconstructed from fish teeth at intermediate/deep Indian <span class="hlt">Ocean</span> pelagic sites (<span class="hlt">Ocean</span> Drilling Program (ODP) Sites 738 and 757 and Deep Sea Drilling Project (DSDP) Site 264), indicate a dominant Southern <span class="hlt">Ocean</span>-sourced contribution to regional deep <span class="hlt">waters</span> (ɛNd(t) = -9.3 ± 1.5). IODP Site U1356 off the coast of Adélie Land, a locus of modern-day Antarctic Bottom <span class="hlt">Water</span> production, is identified as a site of persistent deep <span class="hlt">water</span> formation from the early Eocene to the Oligocene. East of the Tasman Gateway an additional local source of intermediate/deep <span class="hlt">water</span> formation is inferred at ODP Site 277 in the SW Pacific <span class="hlt">Ocean</span> (ɛNd(t) = -8.7 ± 1.5). Antarctic-proximal shelf sites (ODP Site 1171 and Site U1356) reveal a pronounced erosional event between 49 and 48 Ma, manifested by 2 ɛNd unit negative excursions in seawater chemistry toward the composition of bulk sediments at these sites. This erosional event coincides with the termination of peak global warmth following the Early Eocene Climatic Optimum and is associated with documented cooling across the study region and increased export of Antarctic deep <span class="hlt">waters</span>, highlighting the complexity and importance of Southern <span class="hlt">Ocean</span> circulation in the greenhouse climate of the Eocene.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120004248&hterms=freshwater&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfreshwater','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120004248&hterms=freshwater&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dfreshwater"><span>SWOT: The Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography Mission. Wide- Swath Altimetric Elevation on Earth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fu, Lee-Lueng (Editor); Alsdorf, Douglas (Editor); Morrow, Rosemary; Rodriguez, Ernesto; Mognard, Nelly</p> <p>2012-01-01</p> <p>The elevation of the surface of the <span class="hlt">ocean</span> and freshwater bodies on land holds key information on many important processes of the Earth System. The elevation of the <span class="hlt">ocean</span> surface, called <span class="hlt">ocean</span> surface topography, has been measured by conventional nadirlooking radar altimeter for the past two decades. The data collected have been used for the study of large-scale circulation and sea level change. However, the spatial resolution of the observations has limited the study to scales larger than about 200 km, leaving the smaller scales containing substantial kinetic energy of <span class="hlt">ocean</span> circulation that is responsible for the flux of heat, dissolved gas and nutrients between the upper and the deep <span class="hlt">ocean</span>. This flux is important to the understanding of the <span class="hlt">ocean</span>'s role in regulatingfuture climate change.The elevation of the <span class="hlt">water</span> bodies on land is a key parameter required for the computation of storage and discharge of freshwater in rivers, lakes, and wetlands. Globally, the spatial and temporal variability of <span class="hlt">water</span> storage and discharge is poorly known due to the lack of well-sampled observations. In situ networks measuring river flows are declining worldwide due to economic and political reasons. Conventional altimeter observations suffers from the complexity of multiple peaks caused by the reflections from <span class="hlt">water</span>, vegetation canopy and rough topography, resulting in much less valid data over land than over the <span class="hlt">ocean</span>. Another major limitation is the large inter track distance preventing good coverage of rivers and other <span class="hlt">water</span> bodies.This document provides descriptions of a new measurement technique using radar interferometry to obtain wide-swath measurement of <span class="hlt">water</span> elevation at high resolution over both the <span class="hlt">ocean</span> and land. Making this type of measurement, which addresses the shortcomings of conventional altimetry in both oceanographic and hydrologic applications, is the objective of a mission concept called Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography (SWOT), which was recommended by</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://ntrs.nasa.gov/search.jsp?R=20120004248&hterms=Topography&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DTopography','NASA-TRS'); return false;" href="https://ntrs.nasa.gov/search.jsp?R=20120004248&hterms=Topography&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3DTopography"><span>SWOT: The Surface <span class="hlt">Water</span> and <span class="hlt">Ocean</span> Topography Mission. Wide- Swath Altimetric Elevation on Earth</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Fu, Lee-Lueng (Editor); Alsdorf, Douglas (Editor); Morrow, Rosemary; Rodriguez, Ernesto; Mognard, Nelly</p> <p>2012-01-01</p> <p>The elevation of the surface of the <span class="hlt">ocean</span> and freshwater bodies on land holds key information on many important processes of the Earth System. The elevation of the <span class="hlt">ocean</span> surface, called <span class="hlt">ocean</span> surface topography, has been measured by conventional nadirlooking radar altimeter for the past two decades. The data collected have been used for the study of large-scale circulation and sea level change. However, the spatial resolution of the observations has limited the study to scales larger