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Near-Bottom Horizontal Transfer Of Particulate Matter In The Palamós Submarine Canyon (Nw Mediterranean), J. Martin, A. Palanques, P. Puig Jan 2007

Near-Bottom Horizontal Transfer Of Particulate Matter In The Palamós Submarine Canyon (Nw Mediterranean), J. Martin, A. Palanques, P. Puig

Journal of Marine Research

From March to November 2001, six current meters equipped with turbidimeters were moored 12 meters above the bottom inside the Palamós submarine canyon and on the adjacent slope. Horizontal particle fluxes were calculated from current and suspended sediment concentration data. This work aims to evaluate the advective sediment fluxes taking place in the Palamós canyon region, and to discern the nature and time-scales of the processes involved in the across-margin transfer of particles over the study period. Near-bottom currents inside the canyon were constrained by the local topography and displayed a high spatio-temporal variability. The net near-bottom transport of suspended …

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Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann Jan 2007

Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 1. Model Configuration And Ecosystem Dynamics, Baris Salihoglu, Eileen E. Hofmann

Journal of Marine Research

The primary objective of this research is to investigate phytoplankton community response to variations in physical forcing and biological processes in the Cold Tongue region of the equatorial Pacific Ocean at 0N, 140W. This research objective was addressed using a one-dimensional multicomponent lower trophic level ecosystem model that includes detailed algal physiology, such as spectrally-dependent photosynthetic processes and iron limitation on algal growth. The ecosystem model is forced by a one-year (1992) time series of spectrally-dependent light, temperature, and water column mixing obtained from a Tropical Atmosphere-Ocean (TAO) Array mooring. Autotrophic growth is represented by five algal groups, which have …

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Influence Of Environmental Forcings On The Seasonality Of Dissolved Oxygen And Nutrients In The Bay Of Bengal, S. Sardessai, N. Ramaiah, S. Prasanna Kumar, S. N. De Sousa Jan 2007

Influence Of Environmental Forcings On The Seasonality Of Dissolved Oxygen And Nutrients In The Bay Of Bengal, S. Sardessai, N. Ramaiah, S. Prasanna Kumar, S. N. De Sousa

Journal of Marine Research

Studies on seasonal variability of oxygen and nutrients during three seasons namely SW monsoon, fall intermonsoon and spring intermonsoon indicate influence of physical forcings on the distribution of these hydrochemical properties in the subsurface layer. In the open ocean the Minimum Oxygen Layer (MOL ≤10 mu Mol L-1) during the southwest monsoon and fall intermonsoon is mostly confined to the north of 11N due to the penetration of high salinity water in the deeper waters of the central Bay. During spring intermonsoon MOL is mostly confined to the northern region between 14 to 20N with a narrow band …

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A Fast Numerical Solution To The General Mass-Conservation Equation For Solutes And Solids In Aquatic Sediments, Peter Berg, Dennis Swaney, Søren Rysgaard, Bo Thamdrup, Henrik Fossing Jan 2007

A Fast Numerical Solution To The General Mass-Conservation Equation For Solutes And Solids In Aquatic Sediments, Peter Berg, Dennis Swaney, Søren Rysgaard, Bo Thamdrup, Henrik Fossing

Journal of Marine Research

Mathematical modeling of species transformations in aquatic sediments is usually based on numerical solutions to the same general one-dimensional mass-conservation equation and is likely to require substantial computation time. In this paper we present a fast numerical solution to this equation. The solution is suited for both single and multi-component models and it is based on an implicit control volume discretization of the general mass-conservation equation. The solution consists of two algorithms, one that decomposes the discretization matrix once and one that subsequently produces multiple solutions with minimal computational effort. A unique feature of these algorithms is that values of …

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An Assessment Of The Use Of Sediment Traps For Estimating Upper Ocean Particle Fluxes, Ken O. Buesseler, Avan N. Antia, Min Chen, Scott W. Fowler, Wilford D. Gardner, Orjan Gustafsson, Koh Harada, Anthony F. Michaels, Michiel Rutgers Van Der Loeff, Manmohan Sarin, Deborah K. Steinberg, Thomas Trull Jan 2007

An Assessment Of The Use Of Sediment Traps For Estimating Upper Ocean Particle Fluxes, Ken O. Buesseler, Avan N. Antia, Min Chen, Scott W. Fowler, Wilford D. Gardner, Orjan Gustafsson, Koh Harada, Anthony F. Michaels, Michiel Rutgers Van Der Loeff, Manmohan Sarin, Deborah K. Steinberg, Thomas Trull

Journal of Marine Research

This review provides an assessment of sediment trap accuracy issues by gathering data to address trap hydrodynamics, the problem of zooplankton "swimmers," and the solubilization of material after collection. For each topic, the problem is identified, its magnitude and causes reviewed using selected examples, and an update on methods to correct for the potential bias or minimize the problem using new technologies is presented. To minimize hydrodynamic biases due to flow over the trap mouth, the use of neutrally buoyant sediment traps is encouraged. The influence of swimmers is best minimized using traps that limit zooplankton access to the sample …

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Mismatch Between Community Respiration And The Contribution Of Heterotrophic Bacteria In The Ne Atlantic Open Ocean: What Causes High Respiration In Oligotrophic Waters?, Xosé Anxelu G. Morán, Valesca Pérez, Emilio Fernández Jan 2007

Mismatch Between Community Respiration And The Contribution Of Heterotrophic Bacteria In The Ne Atlantic Open Ocean: What Causes High Respiration In Oligotrophic Waters?, Xosé Anxelu G. Morán, Valesca Pérez, Emilio Fernández

Journal of Marine Research

Heterotrophic bacteria have long been considered as the major respirers of the open ocean. During a survey in the eastern N Atlantic Subtropical Gyre we measured 3H-leucine heterotrophic bacterial production (BP), 14C particulate primary production (PPP) and the O2 community metabolism rates: gross primary production (GPP), net community production (NCP) and community respiration (CR). We estimated heterotrophic bacterial respiration (BR) from BP and literature models of bacterial growth efficiency [BGE = BP/(BP + BR)]. BP was an order of magnitude lower than PPP (integrated means of 17 ± 2 and 207 ± 29 mg C m−2 …

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Hurricane-Induced Destratification And Restratification In A Partially-Mixed Estuary, Ming Li, Liejun Zhong, William C. Boicourt, Shunli Zhang, Da-Lin Zhang Jan 2007

Hurricane-Induced Destratification And Restratification In A Partially-Mixed Estuary, Ming Li, Liejun Zhong, William C. Boicourt, Shunli Zhang, Da-Lin Zhang

Journal of Marine Research

Hurricane Isabel made landfall at the Outer Banks of North Carolina and moved past Chesapeake Bay on 18 –19 September 2003. The baroclinic response of this partially-mixed estuary to the passage of Isabel is investigated using the output from a regional atmosphere-ocean model. The hurricane-forced winds caused gradual deepening of the surface mixed layer, followed by rapid destratification in the water-column. The mixed-layer deepening appears to be driven by velocity shear and can be interpreted by a gradient Richardson number. Although strong winds caused complete mixing locally, a large longitudinal salinity gradient of about 10-4 psu m-1 persisted …

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The Variability And Heat Budget Of The Upper Ocean Under The Chile-Peru Stratus, Keir Colbo, Robert Weller Jan 2007

The Variability And Heat Budget Of The Upper Ocean Under The Chile-Peru Stratus, Keir Colbo, Robert Weller

Journal of Marine Research

The persistent stratus clouds found west of Chile and Peru are important for the coupling of the ocean and atmosphere in the eastern Pacific and thus in the climate of the region. The relatively cool sea-surface temperatures found west of Peru and northern Chile are believed to play a role in maintaining the stratus clouds over the region. In October 2000 a buoy was deployed at 20S, 85W, a site near the center of the stratus region, in order to examine the variability of sea-surface temperature and the temporal evolution of the vertical structure of the upper ocean. The buoy …

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Simulated Fiddler-Crab Sediment Mixing, Katherine Huang, Bernard P. Boudreau, Daniel C. Reed Jan 2007

Simulated Fiddler-Crab Sediment Mixing, Katherine Huang, Bernard P. Boudreau, Daniel C. Reed

Journal of Marine Research

Using a lattice-automaton model, we simulate the effects of fiddler crabs on the distribution of excess 210Pb in marsh sediments. Three previously-identified modes of bioturbation are investigated: (1) removal-and-fill, where material is excavated to the sediment-water interface and burrows, when abandoned, are subsequently filled by surface material, (2) removal-and-collapse, where the infilling occurs by collapse of the burrow walls, and (3) partial-compaction-and-collapse, where part of the excavated sediment is packed into the burrow wall and abandoned burrows subsequently collapse. These various mixing modes lead to somewhat different laterally-integrated 210Pbex profiles, which are also influenced …

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Field Investigation On Seawater Temperature Variability In Relation To Horizontal Optical Gradient, Maciej Matciak, Bozena Wojtasiewicz Jan 2007

Field Investigation On Seawater Temperature Variability In Relation To Horizontal Optical Gradient, Maciej Matciak, Bozena Wojtasiewicz

Journal of Marine Research

The spatial variability of radiant energy absorption in seawater can result from the non-homogeneity of the concentration of its optically active components, such as chlorophyll or dissolved organic matter. This non-homogeneity leads to local changes in the radiant heating rate and consequent changes in water temperature. Besides a simple dependence, for instance when a higher phytoplankton concentration is accompanied by a temperature rise, a relation that is more complex may occur. A theoretical analysis suggested that sufficiently strong horizontal changes in seawater absorption may cause, in their close proximity, an additional increase or decrease in the heating rate. To confirm …

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Thermohaline Structure And Variability In The Eastern Nansen Basin As Seen From Historical Data, David Walsh, Igor Polyakov, Leonid Timokhov, Eddy Carmack Jan 2007

Thermohaline Structure And Variability In The Eastern Nansen Basin As Seen From Historical Data, David Walsh, Igor Polyakov, Leonid Timokhov, Eddy Carmack

Journal of Marine Research

Newly available historical Russian data are used to quantify year-to-year variations in the structure and properties of the halocline and Atlantic Water layers in the eastern Nansen Basin. The data come from a series of aerial surveys of the central Arctic Ocean done during winter between 1973 and 1979, and repeated "Polygon" surveys of the shelf, slope, and basin north of Severnaya Zemlya in the 1980s, and thus allow a perspective on shelf-basin exchange. A water-mass census shows substantial survey-to-survey variability in several water-mass categories, with volumetric fluctuations of ∼17% in the Upper Polar Deep Water category, ∼14% in Atlantic …

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Spatial Continuity Of Measured Seawater And Tracer Fluxes Through Nares Strait, A Dynamically Wide Channel Bordering The Canadian Archipelago, Andreas Münchow, Kelly K. Falkner, Humfrey Melling Jan 2007

Spatial Continuity Of Measured Seawater And Tracer Fluxes Through Nares Strait, A Dynamically Wide Channel Bordering The Canadian Archipelago, Andreas Münchow, Kelly K. Falkner, Humfrey Melling

Journal of Marine Research

Freshwater delivered as precipitation and runoff to the North Pacific and Arctic oceans returns to the Atlantic principally via the Canadian polar shelf and Fram Strait. It is conveyed as ice or freshened seawater. Here we use detailed ship-based measurements to calculate a snap-shot of volume, freshwater, and tracer fluxes through Nares Strait, a 500-km long waterway separating Greenland and Ellesmere Island. We use quasi-synoptic observations of current by ship-mounted acoustic Doppler current profiler (ADCP), of salinity and temperature by CTD probe and of dissolved nutrients by rosette bottle sampler on four cross-sections between 82 and 78N latitude. Data were …

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The Role Of Westward Intensification In Potential Vorticity Homogenization, Toshihiro Sakamoto Jan 2007

The Role Of Westward Intensification In Potential Vorticity Homogenization, Toshihiro Sakamoto

Journal of Marine Research

Using a two-layer quasigeostrophic model with weak interfacial and bottom friction we propose a mechanism for potential vorticity homogenization in a non-eddying, wind-driven gyre closed through a viscous western boundary layer, to which the previous theory based on the Prandtl–Batchelor theorem cannot be applied. It is shown that there exist steady states in which the lower-layer potential vorticity in a large pool of closed geostrophic contours becomes substantially uniform. The homogenization process is dominated by advection and thus completed within a single passage through the gyre. This is because an O (1) anomaly of potential vorticity that is comparable to …

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Dissipation In Hydraulic Transitions In Flows Through Abyssal Channels, S. A. Thorpe Jan 2007

Dissipation In Hydraulic Transitions In Flows Through Abyssal Channels, S. A. Thorpe

Journal of Marine Research

There is growing evidence from observations that mixing occurs in hydraulic jumps, or flow transitions, downstream of sills within channels connecting deep ocean basins or within submarine canyons on the flanks of mid-ocean ridges. Models with continuous profiles of velocity and density upstream and downstream of a transition, but conforming to continuity conditions, are devised to represent the mixing that occurs in a hydraulic jump in a stratified shear flow of finite depth moving over a horizontal boundary in a deep fluid. These are used to assess the conditions in which transitions may occur and to provide an estimate of …

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Oxygen And Nitrogen Cycling In The Northeast Pacific – Simulations And Observations At Station Papa In 2003/2004, N. Steiner, S. Vagle, K. Denman, C. Mcneil Jan 2007

Oxygen And Nitrogen Cycling In The Northeast Pacific – Simulations And Observations At Station Papa In 2003/2004, N. Steiner, S. Vagle, K. Denman, C. Mcneil

Journal of Marine Research

A long-term air-sea exchange mooring has been maintained in the North Pacific near Ocean Station Papa (OSP, 145W, 50N) since September 2002 as part of the Canadian Surface Ocean Lower Atmosphere Study (C-SOLAS). The mooring provides a new long-term data set for gas measurements. In addition to Conductivity, Temperature and Depth (CTD) recorders at two depths, the mooring is equipped with ProOceanus Gas Tension Devices (GTDs) measuring the total gas pressure at four different depths, two oxygen sensors, two fluorometers for chlorophyll estimates, and an upward-looking 200 kHz echo-sounder for bubble measurements. Chlorophyll data have been added using SeaWiFS imagery …

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Phytoplankton Pigment Distribution In The Northwestern Alboran Sea And Meteorological Forcing: A Remote Sensing Study, D. Macías, G. Navarro, F. Echevarría, C. M. García, J. L. Cueto Jan 2007

Phytoplankton Pigment Distribution In The Northwestern Alboran Sea And Meteorological Forcing: A Remote Sensing Study, D. Macías, G. Navarro, F. Echevarría, C. M. García, J. L. Cueto

Journal of Marine Research

A set of weekly-composite SeaWiFS (Sea-viewing Wide Field of view Sensor) imagery (from 1998 to 2004) has been used to asses the temporal and spatial variability of the surface chlorophyll distribution in the Northwestern Alboran Sea. Empirical Orthogonal Function (EOF) analysis of the images series shows the existence of three different regions in which surface chlorophyll presents a homogeneous temporal behavior in the neighborhood of the Strait of Gibraltar.The temporal patterns of surface chlorophyll concentrations in each region have been characterized by studying the role of several forcing factors, mainly the zonal component of the wind field.The first identified region …

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The Geography Of Linear Baroclinic Instability In Earth’S Oceans, K. Shafer Smith Jan 2007

The Geography Of Linear Baroclinic Instability In Earth’S Oceans, K. Shafer Smith

Journal of Marine Research

Satellite observations reveal a mesoscale oceanic circulation dominated by turbulence that is correlated, in most cases, with local baroclinicity. Linear baroclinic instability theory has proved useful in understanding the time and space scales of atmospheric eddies. The question addressed here is, to what degree can the observed oceanic eddy activity be understood through a local, linear stability analysis? This question is addressed as follows. A local quasigeostrophic linear stability calculation is performed on a grid of wavenumbers, ranging in magnitude about the local deformation wavenumber, for each vertical profile in a dataset of neutral density for the world's oceans. The …

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Transient Tracer Dynamics In A Lattice-Automaton Model Of Bioturbation, Daniel C. Reed, Bernard P. Boudreau, Katherine Huang Jan 2007

Transient Tracer Dynamics In A Lattice-Automaton Model Of Bioturbation, Daniel C. Reed, Bernard P. Boudreau, Katherine Huang

Journal of Marine Research

Mixing of sediments by benthic fauna represents a dominant transport process of solids in the majority of surficial marine deposits. Short-term mixing rates are often determined by fitting a transient, diffusive model of bioturbation to vertical profiles of introduced particles (e.g., luminophores). Previous field studies adopting this approach have noted that mixing intensity decreases with time and the nature of mixing progresses from advective or nonlocal transport to diffusive mixing. These observations have been attributed to "age-dependent" mixing. The present study employs a lattice-automaton model to investigate the short-term behavior of conservative transient tracers. Simulations demonstrate that despite constant, indiscriminate …

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On The Vorticity Cycle Of The Loop Current, A. Lugo-Fernández, A. Badan Jan 2007

On The Vorticity Cycle Of The Loop Current, A. Lugo-Fernández, A. Badan

Journal of Marine Research

The inrushing/retraction behavior of the Loop Current (LC) in the eastern Gulf of Mexico can be represented by a recurrent cycle of vorticity input/output with a time scale of 0 to 16 months. This cycle is brought about as a balance between the accumulation of absolute vorticity in the LC and deep advection of vorticity to the Caribbean Sea. The vorticity time scale is directly proportional to the change in circulation around the LC and 2πH/Q0(f0 + ζ0); where H (∼800 m) is the thickness of the LC, Q0 is …

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The Enso Signature In Sea-Surface Temperature In The Gulf Of California, Hugo Herrera-Cervantes, Daniel B. Lluch-Cota, Salvador E. Lluch-Cota, Guillermo Gutiérrez-De-Velasco S Jan 2007

The Enso Signature In Sea-Surface Temperature In The Gulf Of California, Hugo Herrera-Cervantes, Daniel B. Lluch-Cota, Salvador E. Lluch-Cota, Guillermo Gutiérrez-De-Velasco S

Journal of Marine Research

We analyzed 21 years of sea-surface temperature satellite images to explore the spatial signature of the El Niño-Southern Oscillation signal in the Gulf of California. We used empirical orthogonal function analysis to extract the principal mode of the nonseasonal sea-surface temperature variability and compared it to the spatial signature of the Southern Oscillation Index. The first mode accounted for 80% of nonseasonal variability and its amplitude time series was significantly correlated to the Southern Oscillation Index (r = −0.58,P < 0.01). The amplitude of this mode and its statistical relation to the El Niño is stronger during winter, which suggests that forcing of sea-surface temperature variability occurs through the disruption of the wind-driven upwelling corridor along the eastern coast due to El Niño-related atmospheric teleconnections. We also examined weekly time series of coastal sea-surface temperature coastal anomalies along the coast of North America, including the interior of the Gulf of California, during the strong 1997–98 El Niño. We found a poleward propagating signal that reached the mouth of the Gulf of California at the end of spring and continued its poleward propagation along the west coast of the peninsula slightly delayed; it also resulted in warming inside the Gulf of California. This observation may provide an explanation for the variable extension of the El Niño signature along the Pacific coast of North America.

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Water Column Stability And Spring Bloom Dynamics In The Gulf Of Alaska, Stephanie A. Henson Jan 2007

Water Column Stability And Spring Bloom Dynamics In The Gulf Of Alaska, Stephanie A. Henson

Journal of Marine Research

The initiation of the Gulf of Alaska phytoplankton spring bloom is light limited, and therefore the onset of stratification is critical to primary productivity. A stability ratio, which represents the balance between mixing (tide and wind) and buoyancy (heat and freshwater) processes, is defined. When buoyancy dominates over mixing, stratification is possible. Use of model- and satellite-derived data allows maps of the spatial and temporal development of stratification to be constructed. Spatial variability in the dominant forcing components is also mapped. The onset of water column stability is closely linked to the timing of the phytoplankton spring bloom. Consideration of …

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Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 2. Effects Of Physical And Biogeochemical Processes, Baris Salihoglu, Eileen E. Hofmann Jan 2007

Simulations Of Phytoplankton Species And Carbon Production In The Equatorial Pacific Ocean 2. Effects Of Physical And Biogeochemical Processes, Baris Salihoglu, Eileen E. Hofmann

Journal of Marine Research

A one-dimensional multi-component lower trophic level ecosystem model that includes detailed algal physiology is used to investigate the response of phytoplankton community and carbon production and export to variations in physical and biochemical processes in the Cold Tongue region of the equatorial Pacific Ocean at 0N, 140W. Results show that high-frequency variability in vertical advection and temperature is an important mechanism driving the carbon export. Filtering out low frequency physical forcing results in a 30% increase in primary production and dominance of high-light adapted Prochlorococcus and autotrophic eukaryotes. Sensitivity studies show that iron availability is the primary control on carbon …

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Rapid Consumption Of Phytoplankton And Ice Algae By Arctic Soft-Sediment Benthic Communities: Evidence Using Natural And 13c-Labeled Food Materials, Ming-Yi Sun, Michael L. Carroll, William G. Ambrose Jr., Lisa M. Clough, Li Zou, Glenn R. Lopez Jan 2007

Rapid Consumption Of Phytoplankton And Ice Algae By Arctic Soft-Sediment Benthic Communities: Evidence Using Natural And 13c-Labeled Food Materials, Ming-Yi Sun, Michael L. Carroll, William G. Ambrose Jr., Lisa M. Clough, Li Zou, Glenn R. Lopez

Journal of Marine Research

Reduction of sea ice in the Arctic may significantly alter the relative fluxes of phytoplankton and ice algae to the seafloor. To examine the response of Arctic benthic communities to changing food supplies, we incubated sediment cores collected from two sites (Smeerenburg Fjord, northwest Svalbard in May 2003 and Storfjord Trench, Barents Sea in May 2004) with controlled additions of natural phytoplankton and ice algal assemblages, and laboratory-cultured 13C-labeled ice algae (Nitzschia frigida, in 2004 only). We measured sediment respiration, pigments, lipid biomarkers, and compound-specific δ13C signals over the course of incubations. Both communities responded …

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Modeling Sensitivity Of Biodiffusion Coefficient To Seasonal Bioturbation, Pascal Lecroart, Sabine Schmidt, Pierre Anschutz, Jean-Marie Jouanneau Jan 2007

Modeling Sensitivity Of Biodiffusion Coefficient To Seasonal Bioturbation, Pascal Lecroart, Sabine Schmidt, Pierre Anschutz, Jean-Marie Jouanneau

Journal of Marine Research

Biodiffusion coefficient is the predominant parameter used to constrain biological activity in marine sediments. Bioturbation characterization is important because of the dominant role it plays on the flux determination through the sediment-water interface. Biological mixing is quantified through models of radionuclides diagenesis by both a biodiffusion coefficient (Db) and a mixed depth (L) under the basic steady-state assumption. Based on a new global compilation of radionuclide data in marine sediments and on previously published modeling results, we show that short-live radionuclides are perfectly devoted to quantify biological mixing for sediments associated with λL2/Db lower than 125, λ representing …

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Notes On The Modeling Of Methane In Aging Hydrothermal Plumes, G. C. Nihous, S. M. Masutani Jan 2007

Notes On The Modeling Of Methane In Aging Hydrothermal Plumes, G. C. Nihous, S. M. Masutani

Journal of Marine Research

Marine hydrothermal vent fields represent a unique environment for the study of aerobic microbial methane oxidation because of high methane concentrations and limited spatial and temporal scales. Earlier data collected in lateral plumes at the Endeavour Segment of the Juan de Fuca Ridge, including methane concentration, methane oxidation rate and stable carbon isotopic composition (δ13C), are carefully interpreted with a suite of simple analytical models. Methane oxidation is defined with a rate constant k as a first order process with respect to both substrate and methanotroph concentration. This elementary formalism coupled with simplified representations of advection and …

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Greenland’S Island Rule And The Arctic Ocean Circulation, Terrence M. Joyce, Andrey Proshutinsky Jan 2007

Greenland’S Island Rule And The Arctic Ocean Circulation, Terrence M. Joyce, Andrey Proshutinsky

Journal of Marine Research

In order to explain observed southward water transport of 2-3 Sv through Davis Strait, a simple extension of Godfrey's (1989) Island Rule and a 2-D idealized numerical model simulations were made for the flow around Greenland. Godfrey's theory has been extended to permit inclusion of Bering Strait inflow and bottom friction to represent the dissipation supplied by the porous Canadian Archipelago in the modeled flow west of Greenland. In both models, the forcing has been applied in a quasi-steady manner to the circulation via climatologic wind stresses and using wind forcing for the high and low Arctic Oscillation (AO) index …

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Review Of The Crevalle Jacks, Caranx Hippos Complex (Teleostei: Carangidae), With A Description Of A New Species From West Africa, William F. Smith-Vaniz, Kent E. Carpenter Jan 2007

Review Of The Crevalle Jacks, Caranx Hippos Complex (Teleostei: Carangidae), With A Description Of A New Species From West Africa, William F. Smith-Vaniz, Kent E. Carpenter

Biological Sciences Faculty Publications

The Caranx hippos species complex comprises three extant species: crevalle jack (Caranx hippos) (Linnaeus, 1766) from both the western and eastern Atlantic oceans; Pacific crevalle jack (Caranx caninus) Günther,1868 from the eastern Pacific Ocean; and longfin crevalle jack (Caranx fischeri) new species, from the eastern Atlantic, including the Mediterranean Sea and Ascension Island. Adults of all three species are superficially similar with a black blotch on the lower half of the pectoral fin, a black spot on the upper margin of opercle, one or two pairs of enlarged symphyseal canines on the lower jaw, …

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Fortnightly Variability At The Transition Between Two Sub-Estuaries, Mayra Lorena Riveron Enzastiga Jul 2006

Fortnightly Variability At The Transition Between Two Sub-Estuaries, Mayra Lorena Riveron Enzastiga

OES Theses and Dissertations

Profiles of current velocity from an Acoustic Doppler Current Profiler (ADCP) and of water salinity, temperature and density from a Conductivity-Temperature-Depth (CTD) recorder, were combined with surface salinity, temperature and density from a Conductivity-Temperature (CT) recorder to elucidate the fortnightly variability at the Lafayette River entrance. The Lafayette River connects at its mouth with the Elizabeth River, which is a tributary to the James River in the Chesapeake Bay. Data were collected in four experiments during consecutive spring and neap tides in the autumn of 2000, and in the spring of 2001. Each experiment was carried out for -25 hours …

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Constraining Bubble Dynamics And Mixing With Dissolved Gases: Implications For Productivity Measurements By Oxygen Mass Balance, Roberta C. Hamme, Steven R. Emerson Jan 2006

Constraining Bubble Dynamics And Mixing With Dissolved Gases: Implications For Productivity Measurements By Oxygen Mass Balance, Roberta C. Hamme, Steven R. Emerson

Journal of Marine Research

We used a dynamic mixed layer model to determine carbon export by the oxygen mass balance method from a time series of O2/Ar, N2/Ar and Ne measurements collected at station ALOHA near Hawaii from July 2000 to June 2001. The inert gas measurements constrain the flux of oxygen into the mixed layer from small, collapsing bubbles (injection) to be greater than or equal to the flux from larger bubbles (exchange), with mean estimates of the ratio in the range of 1–2. We also show that monthly observations of temperature and inert gases cannot constrain the rate …

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Generalized Inversion Of The Gent-Cane Model Of The Tropical Pacific With Tropical Atmosphere-Ocean (Tao) Data, A. F. Bennett, B. S. Chua, H. E. Ngodock, D. E. Harrison, M. J. Mcphaden Jan 2006

Generalized Inversion Of The Gent-Cane Model Of The Tropical Pacific With Tropical Atmosphere-Ocean (Tao) Data, A. F. Bennett, B. S. Chua, H. E. Ngodock, D. E. Harrison, M. J. Mcphaden

Journal of Marine Research

We here describe the results of our latest effort to reanalyze TAO monthly mean surface and subsurface temperature observations constrained by a tropical Pacific ocean model, and simultaneously to evaluate the physical consistency of the observations and the model. Both tasks are executed by weak–constraint, four–dimensional variational assimilation of the observations into the model. In this study our reanalysis employs the reduced–gravity Gent–Cane model, combined with the 'KPP–interior' parameterization of vertical turbulent fluxes. With the limited vertical resolution adopted in previous studies of this model, the 'W4DVAR' or inverse method fails to produce an acceptable reanalysis, as the dynamical residuals …

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