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Refractory Organic Compounds In Polar Waters: Relationship Between Humic Substances And Amino Acids In The Arctic And Antarctic, Ulrike Hubberten, Rubén J. Lara, Gerhard Kattner Jan 1995

Refractory Organic Compounds In Polar Waters: Relationship Between Humic Substances And Amino Acids In The Arctic And Antarctic, Ulrike Hubberten, Rubén J. Lara, Gerhard Kattner

Journal of Marine Research

A synopsis of data on the amino acid compositions of Arctic and Antarctic seawater, XAD-fractions of dissolved organic matter (DOM) and suspended particulate organic material (POM) is presented. Total dissolved amino acids (TDAA) correlated highly significantly with dissolved organic nitrogen (DON), representing about 11% of DON in unfractionated filtered seawater. Average DON values were similar with ca. 3–4 μM N in the Arctic and Antarctic. Differences in amino acid distribution and composition patterns in particulate and dissolved material suggest the selective preservation or utilization of certain amino acids. In POM, glycine, alanine, glutamic acid, aspartic acid and serine made up …

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Choked Flows And Wind-Driven Interbasin Exchange, Doron Nof Jan 1995

Choked Flows And Wind-Driven Interbasin Exchange, Doron Nof

Journal of Marine Research

The classical question of how much water flows from one ocean to the other via connecting passages is addressed with a nonlinear analytical model. The focus is on gaps that are too broad to be influenced by the so-called “hydraulic control” and yet too narrow to allow free (“unchoked”) flow through them. We consider two rectangular oceanic basins, one containing a light upper layer overlying a slightly heavier deep layer and the other containing only one layer of fluid (whose density is identical to that of the lower fluid in the first basin). The basins are separated by a thin …

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Benthic Respiration And Nitrogen Release In Buzzards Bay, Massachusetts, Gary T. Banta, Anne E. Giblin, John E. Hobbie, Jane Tucker Jan 1995

Benthic Respiration And Nitrogen Release In Buzzards Bay, Massachusetts, Gary T. Banta, Anne E. Giblin, John E. Hobbie, Jane Tucker

Journal of Marine Research

The decomposition of organic matter and the regeneration of nitrogen in the sediments of Buzzards Bay, Massachusetts were examined by measuring benthic fluxes of oxygen and dissolved inorganic nitrogen (DIN). Benthic respiration (O2 consumption) rates measured from one site yielded an estimate of 65–80 g C m−2 oxidized annually. Comparing the annual release of DIN with the consumption of O2 led to an estimate of N loss from the benthic-pelagic system, most likely as N2 gas via denitrification, corresponding to 14–32% of the N remineralized from organic matter decomposition. Using path analysis, benthic flux rates of …

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Observations Of The Influence Of Diurnal Convection On Upper Ocean Dissolved Gas Measurements, Craig L. Mcneil, David M. Farmer Jan 1995

Observations Of The Influence Of Diurnal Convection On Upper Ocean Dissolved Gas Measurements, Craig L. Mcneil, David M. Farmer

Journal of Marine Research

An important example of the interaction between biological productivity and near-surface oceanography is the role of nocturnal convection and diurnal restratification in modifying the environment in which photosynthetic activity takes place. In situ time series measurements of dissolved oxygen reveal the effects of photosynthetic activity, respiration and redistribution by mixing. Moored thermistor time series and frequent CTD casts show that restratification during the day is confined to a warmer shallow surface layer where most of the biological production is expected to occur. The depth and rate of mixing is measured with neutrally buoyant floats which track the vertical excursions of …

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Vorticity Balance Of Boundary Currents, G. T. Csanady, J. L. Pelegri Jan 1995

Vorticity Balance Of Boundary Currents, G. T. Csanady, J. L. Pelegri

Journal of Marine Research

Friction at the seafloor acts as a source of potential vorticity (PV) for individual isopycnic layers of a boundary current. The rate of PV transport (flux times layer thickness) equals, to a good approximation, the divergence of alongstream shear stress in the bottom boundary layer at the seafloor, which in turn equals the alongstream gradient of Montgomery potential. Mean PV transport is continuous along isopycnals between the bottom boundary layer and a boundary current in statistically steady state. Within the boundary current, Reynolds flux of vorticity transports PV. The divergence of this transport balances planetary vorticity advection and other terms …

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Local And Remote Forcing Of The Barotropic Transport Through A Periodic Gap In A Basin With Bottom Topography, Alexander Krupitsky Jan 1995

Local And Remote Forcing Of The Barotropic Transport Through A Periodic Gap In A Basin With Bottom Topography, Alexander Krupitsky

Journal of Marine Research

The effect of bottom topography H on the barotropic transport through a periodic gap in a basin with large-scale bottom topography is studied. The results obtained generalize previous findings for the case of a zonal channel (Wang and Huang, 1995; Krupitsky and Cane, 1994). An asymptotic approximation is found for the zonal transport on a β-plane when all f/H isolines are blocked by the solid boundaries. It is shown that to leading order, the transport through the gap (i) is independent of friction similar to a western boundary current; (ii) is inversely proportional to R, the range of values …

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Coastal Sea Surface Temperature Variability Along The South Coast Of South Africa And The Relationship To Regional And Global Climate, E. H. Schumann, A. L. Cohen, M. R. Jury Jan 1995

Coastal Sea Surface Temperature Variability Along The South Coast Of South Africa And The Relationship To Regional And Global Climate, E. H. Schumann, A. L. Cohen, M. R. Jury

Journal of Marine Research

The southern coastline of South Africa is approximately zonal, with a wide (up to 270 km) shelf region. Intense thermoclines are known to be established by insolation on the inner shelf region during summer, upwelling is generated by easterly-component winds, and occasionally Agulhas Current water can be advected close to the coast, particularly in the east. These processes induce daily and seasonal fluctuations of coastal sea-surface temperature (SST), but their influence over longer time scales (interannual) has not yet been tested. Here time series of SST ranging from 12 to 31 years are examined for inter-relationships with local and regional …

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Estimates Of Turbulence Parameters From Lagrangian Data Using A Stochastic Particle Model, Annalisa Griffa, Kenneth Owens, Leonid Piterbarg, Boris Rozovskii Jan 1995

Estimates Of Turbulence Parameters From Lagrangian Data Using A Stochastic Particle Model, Annalisa Griffa, Kenneth Owens, Leonid Piterbarg, Boris Rozovskii

Journal of Marine Research

A new parametric approach for the study of Lagrangian data is presented. It provides parameter estimates for velocity and transport components and is based on a stochastic model for single particle motion. The main advantage of this approach is that it provides more accurate parameter estimates than existing methods by using the a-priori knowledge of the model. Also, it provides a complete error analysis of the estimates and is valid in presence of observation errors. Unlike nonparametric methods (e.g. Davis, 1991b), our technique depends on a-priori assumptions which require that the model validity be checked in order to obtain reliable …

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Photochemistry, Mixing And Diurnal Cycles In The Upper Ocean, Scott C. Doney, Raymond G. Najjar, Scott Stewart Jan 1995

Photochemistry, Mixing And Diurnal Cycles In The Upper Ocean, Scott C. Doney, Raymond G. Najjar, Scott Stewart

Journal of Marine Research

The interplay between ocean photochemistry and surface boundary-layer physics is explored in a range of analytical and numerical process models. For simple systems, key attributes of the photochemical distribution—diurnal cycle, surface concentration, and the bulk concentration difference across the “mixed layer”—can be expressed in terms of a small number of physical (vertical diffusivity) and photochemical (turnover timescale and production depth scale) scaling factors. A coupled, 1-D photochemical/physical model is used to examine the more general case with finite mixing rates, variable photochemical production and evolving boundary layer depth. Finite boundary layer mixing rates act to increase both the diurnal cycle …

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Chemical Tracers Of Biological Processes In Shallow Waters Of North Pacific: Preformed Nitrate Distributions, Steven Emerson, Thomas L. Hayward Jan 1995

Chemical Tracers Of Biological Processes In Shallow Waters Of North Pacific: Preformed Nitrate Distributions, Steven Emerson, Thomas L. Hayward

Journal of Marine Research

Distributions of nitrate and Apparent Oxygen Utilization in the upper subtropical North Pacific Ocean reveal a layer with negative values of preformed nitrate. This layer occurs at depths just below the 1% light level and above the density of sigma theta 25.6. We show that large-scale spatial patterns in the distribution of this feature are determined by an interaction between light penetration and the depth of isopycnal surfaces which are ventilated in nutrient rich surface waters. Although the data alone are insufficient to distinguish between several possible causes, we believe the geographic and depth distributions of the negative preformed nitrate …

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The Mean Circulation Of The Atlantic Ocean North Of 30s Determined With The Adjoint Method Applied To An Ocean General Circulation Model, Andreas Schiller Jan 1995

The Mean Circulation Of The Atlantic Ocean North Of 30s Determined With The Adjoint Method Applied To An Ocean General Circulation Model, Andreas Schiller

Journal of Marine Research

The large-scale mean circulation of the Atlantic Ocean is examined using a general circulation model (GCM) and its approximate adjoint. A cost function is specified that requires the model inputs to be consistent with hydrographic observations and observed air-sea fluxes of heat and freshwater, whereas the velocity field has to adjust to the modified thermohaline initial and boundary conditions. The optimized, quasi-steady model state is closer to the observed circulation state than previous prognostic steady-state models of comparable resolution. However, it is only partially consistent with the error estimates derived from the observations. In the western boundary region large deviations …

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Dynamics Of Circulation Of The Japan Sea, Greg Holloway, Tessa Sou, Michael Eby Jan 1995

Dynamics Of Circulation Of The Japan Sea, Greg Holloway, Tessa Sou, Michael Eby

Journal of Marine Research

Including mean flow forcing due to eddy-topography interaction in a numerical model of the Japan Sea appears to improve defects identified in previous modelling studies. Characteristic western boundary current overshoot (by the East Korea Warm Current) is reduced or eliminated while a southward undercurrent brings colder, fresher water along the Korean coast. Cyclonic circulation in the north includes a strengthened Liman Current. A more nearly continuous Nearshore Branch follows the Honshu shelf break with northward-flowing undercurrent. Interannual variability persists under fixed (seasonally repeating or annual mean) external forcing.

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Multiple Solutions And Advection-Dominated Flows In The Wind-Driven Circulation. Part I: Slip, Glenn R. Ierley, Vitalii A. Sheremet Jan 1995

Multiple Solutions And Advection-Dominated Flows In The Wind-Driven Circulation. Part I: Slip, Glenn R. Ierley, Vitalii A. Sheremet

Journal of Marine Research

We consider steady solutions of the barotropic quasigeostrophic vorticity equation for a single subtropical gyre with dissipation in the form of lateral friction. Solutions are governed by two parameters: inertial boundary-layer width; and viscous boundary-layer width. Numerical computations for slip conditions indicate a wedge-shaped region in this two-dimensional parameter space, where three solutions coexist. One of these is a viscous solution with weak recirculation; one a solution of intermediate recirculation; and one a strongly nonlinear recirculation gyre. Parametric scalings based on elementary solutions are numerically corroborated as the first and third of these solutions are continued away from the vicinity …

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Carbon Cycling In Mesohaline Chesapeake Bay Sediments 1: Poc Deposition Rates And Mineralization Pathways, Eric E. Roden, Jon H. Tuttle, Walter R. Boynton, W. Michael Kemp Jan 1995

Carbon Cycling In Mesohaline Chesapeake Bay Sediments 1: Poc Deposition Rates And Mineralization Pathways, Eric E. Roden, Jon H. Tuttle, Walter R. Boynton, W. Michael Kemp

Journal of Marine Research

Organic carbon cycling in sediments at two locations in the mesohaline Chesapeake Bay was analyzed using available data on sediment sulfate reduction, sediment oxygen consumption, and particulate organic carbon (POC) deposition and burial. Estimates of POC deposition based on the sum of integrated sediment metabolism and POC burial compared well with direct estimates derived from chlorophyll-a collection rates in mid-water column sediment traps. The range of POC deposition estimates (15–31 mol C m−2 yr−1) accounted for a large fraction (36–74%) of average annual net primary production in the mesohaline Bay. The difference between rates of POC …

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Structure Of An Inertial Deep Western Boundary Current, Robert S. Pickart, Rui Xin Huang Jan 1995

Structure Of An Inertial Deep Western Boundary Current, Robert S. Pickart, Rui Xin Huang

Journal of Marine Research

An inertial model of the deep western boundary current (DWBC) is presented where the cross-stream distribution of potential vorticity varies in a realistic fashion. The case of uniform potential vorticity, which has been solved earlier, is included for comparison. The potential vorticity distribution used in the model is obtained from a hydrographic density section across the North Atlantic DWBC. The model solutions using this distribution differ significantly from the uniform potential vorticity case. Most notably the current is wider and weaker with substantially reduced relative vorticity, more indicative of observed DWBCs. The addition of an exponential continental slope leads to …

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Simultaneous Nitrate And Oxygen Respiration In Coastal Sediments: Evidence For Discrete Diagenesis, Jay A. Brandes, Allan H. Devol Jan 1995

Simultaneous Nitrate And Oxygen Respiration In Coastal Sediments: Evidence For Discrete Diagenesis, Jay A. Brandes, Allan H. Devol

Journal of Marine Research

Oxygen and nitrate porewater profiles from sediments of Puget Sound, the Washington continental margin, and the Chukchi Sea were determined using a whole core squeezing apparatus. The two oxidants were observed to have equal sediment penetration depths and similar profile shapes in nearly all cores. Oxygen and nitrate, therefore, behaved in a similar manner in these shallow sediments: an observation that is not consistent with existing models of sediment diagenesis. A two-dimensional model was constructed in which nearly all oxidant (O2 and NO3−)consumption took place in scattered, highly reactive discrete micro-sites. The model produced a sedimentary …

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Shelf Harpacticoid Copepods Do Not Escape Into The Seabed During Winter Storms, David Thistle, Georges L. Weatherly, Stephen C. Ertman Jan 1995

Shelf Harpacticoid Copepods Do Not Escape Into The Seabed During Winter Storms, David Thistle, Georges L. Weatherly, Stephen C. Ertman

Journal of Marine Research

Winter storms on temperate shelves frequently rework bottom sediments. When the sediment is put in motion, sediment-dwelling harpacticoid copepods risk being suspended. We tested for evidence that adult harpacticoids move below the layer of reworked sediment to avoid suspension. To do so, we determined the rate at which a moderate storm at a site at 18 m depth in the northern Gulf of Mexico (29° 40.63′N, 84° 22.80′W) exposed subsurface sediment during bed-form development and then subjected intact cores from that site to a similar rate of exposure in a laboratory flume. We found no significant difference in vertical position …

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Potential Flow Artifacts Associated With Benthic Experimental Gear: Deep-Sea Mudbox Examples, Paul V. R. Snelgrove, Cheryl Ann Butman, J. Frederick Grassle Jan 1995

Potential Flow Artifacts Associated With Benthic Experimental Gear: Deep-Sea Mudbox Examples, Paul V. R. Snelgrove, Cheryl Ann Butman, J. Frederick Grassle

Journal of Marine Research

In response to the growing recognition of the potential effects of near-bed hydrodynamics on various benthic processes, flume studies were conducted to document fine-scale flow patterns over several types of mudboxes that have been used to study colonization by deep-sea organisms. Mudboxes are typically filled with natural sediments or sediment treatments and placed in the field to observe how timing, larval supply and sediment composition may affect larval settlement. This study addresses potential hydrodynamic biases of mudbox structures as obstructions to the near-bed flow. Detailed velocity profiles were made over two types of “free vehicle” mudboxes that could be deployed …

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Descent Of Dense Water Masses Along Continental Slopes, Scott A. Condie Jan 1995

Descent Of Dense Water Masses Along Continental Slopes, Scott A. Condie

Journal of Marine Research

The formation of dense water over the continental shelf and its descent along the continental slope have been investigated both theoretically and experimentally. Models have been developed for slope fronts and dense filaments, with emphasis on the role of the bottom boundary layer. An analytical, two-layer, two-dimensional model is first presented for the development of dense slope fronts near the shelf-break. The effects of vertical viscosity are explored and two behavioral regimes identified. The most relevant regime is determined by the parameter F = (UQ/gεs)(f3/v)1/2 where UQ is the flux …

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The Growth Of Convective Plumes At Seafloor Hot Springs, Kevin G. Speer, John Marshall Jan 1995

The Growth Of Convective Plumes At Seafloor Hot Springs, Kevin G. Speer, John Marshall

Journal of Marine Research

The growth of buoyant plumes in the presence of stratification (N) and rotation (f) is studied and illustrated with a number of numerical experiments of convection induced by a localized source of buoyancy at the lower boundary of a linearly stratified fluid. The presence of stratification constrains the convection in the vertical giving rise to an equilibrium-spreading layer which receives the rising mass of plume fluid; the plume can be divided into an upper, mass-source driven anticyclone and a lower, buoyancy-source (F) driven cyclone. With N/f large, the plume's rise-height is set by the …

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An Estimate Of The Climatological Mean Circulation In The Western North Atlantic, Wei Wang, M. Susan Lozier Jan 1995

An Estimate Of The Climatological Mean Circulation In The Western North Atlantic, Wei Wang, M. Susan Lozier

Journal of Marine Research

In order to produce a long-term mean circulation pattern for the western North Atlantic, geostrophic velocities have been calculated using a recently-assembled hydrographic database comprised of NODC station data from 1904–1990. The property fields generated from this database are smoothed on isopycnal surfaces and have a nominal resolution of one degree for the spatial domain of this study (34–42N, 48–66W). To reference the geostrophic velocities, SOFAR float data over the period 1972–1990 are used. The flow fields from this calculation are compared to fields produced using an assumed level of no motion. The calculations employing float data yield a flow …

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Trade And The Environment: Does Environmental Diversity Detract From The Case For Free Trade?, T.N. Srinivasan, Jagdish Bhagwati Jan 1995

Trade And The Environment: Does Environmental Diversity Detract From The Case For Free Trade?, T.N. Srinivasan, Jagdish Bhagwati

Discussion Papers

No abstract provided.

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Integrated Approaches To Human Resource Development, T. Paul Schultz Jan 1995

Integrated Approaches To Human Resource Development, T. Paul Schultz

Discussion Papers

No abstract provided.

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Measuring Aggregate Human Capital, Xavier Sala-I-Martin, Casey B. Mulligan Jan 1995

Measuring Aggregate Human Capital, Xavier Sala-I-Martin, Casey B. Mulligan

Discussion Papers

No abstract provided.

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Women's Role In The History Of The World Student Christian Federation, 1895-1945, Johanna M. Selles Jan 1995

Women's Role In The History Of The World Student Christian Federation, 1895-1945, Johanna M. Selles

Yale Divinity Library Occasional Publications

No abstract provided.

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The Effects Of Hyperbaric Exposure On Bone Cell Activity In The Rat : Implications For The Pathogenesis Of Dysbaric Osteonecrosis, Stephanie Anne Kapfer Jan 1995

The Effects Of Hyperbaric Exposure On Bone Cell Activity In The Rat : Implications For The Pathogenesis Of Dysbaric Osteonecrosis, Stephanie Anne Kapfer

Yale Medicine Thesis Digital Library

No abstract provided.

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Autoantibodies In Systemic Lupus Erythematosus, Ingrid Helena Olhoffer Jan 1995

Autoantibodies In Systemic Lupus Erythematosus, Ingrid Helena Olhoffer

Yale Medicine Thesis Digital Library

No abstract provided.

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The Effects Of Antiparasitic Medications On The Nutritional Status Of Children From A Parish In Rural Ecuador, Marjorie S. Rosenthal Jan 1995

The Effects Of Antiparasitic Medications On The Nutritional Status Of Children From A Parish In Rural Ecuador, Marjorie S. Rosenthal

Yale Medicine Thesis Digital Library

No abstract provided.

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In-Vivo Study Of Inhibition In The Human Hippocampus, Kenneth Patrick Vives Jan 1995

In-Vivo Study Of Inhibition In The Human Hippocampus, Kenneth Patrick Vives

Yale Medicine Thesis Digital Library

No abstract provided.

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Long-Term Computed Tomography Follow-Up Of Sphenoid/Sellar Skull Base Reconstruction After Transsphenoidal Surgery, Nora E. Canty Jan 1995

Long-Term Computed Tomography Follow-Up Of Sphenoid/Sellar Skull Base Reconstruction After Transsphenoidal Surgery, Nora E. Canty

Yale Medicine Thesis Digital Library

No abstract provided.

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