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Biological oceanography

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Composition And Degradation Of Salp Fecal Pellets: Implications For Vertical Flux In Oceanic Environments, David A. Caron, Laurence P. Madin, Jonathan J. Cole Jan 1989

Composition And Degradation Of Salp Fecal Pellets: Implications For Vertical Flux In Oceanic Environments, David A. Caron, Laurence P. Madin, Jonathan J. Cole

Journal of Marine Research

Changes in the sinking rates, ash-free dry weights, particulate carbon and nitrogen content, and carbon:nitrogen ratios from the fecal pellets of several species of oceanic salps were examined in ten-day decomposition studies. Although bacteria and protozoa became abundant in the incubation vessels, most of the fecal pellets remained physically intact throughout the study. Bacterial activity in the pellets (measured by the rate of uptake of 3H-thymidine) increased, but microbial degradation had little effect on the sinking speeds of most of the fecal pellets. The average losses of ash-free dry weight and carbon and nitrogen content, along with changes in …


Oxygen, Sulfide And Diffusion: Why Thiobiotic Meiofauna Must Be Sulfide-Insensitive First-Order Respirers, Eric Powell Jan 1989

Oxygen, Sulfide And Diffusion: Why Thiobiotic Meiofauna Must Be Sulfide-Insensitive First-Order Respirers, Eric Powell

Journal of Marine Research

Thiobios (sulfide-dependent) meiofauna have an aerobic metabolism, are sulfide-insensitive and rarely contain symbiotic sulfur-oxidizing bacteria. Adaptations so far observed in thiobios are consistent with the overriding need to maximize the diffusive flux of oxygen and sulfide to optimize energy yield. Both accrue from the requirement that oxygen and sulfide uptake and metabolism be controlled by diffusion and first-order rate reactions. These adaptations include variation in shape, mitochondrial distribution and respiratory capacity. Meiofauna can substantially supplement a more inefficient anaerobic metabolism with aerobic metabolism at oxygen concentrations as low as 0.1 μM. Hence, an aerobic capacity is useful even in …


A Brownian-Pumping Model For Oceanic Trace Metal Scavenging: Evidence From Th Isotopes, B. D. Honeyman, P. H. Santschi Jan 1989

A Brownian-Pumping Model For Oceanic Trace Metal Scavenging: Evidence From Th Isotopes, B. D. Honeyman, P. H. Santschi

Journal of Marine Research

Two observed characteristics of Th isotope and stable metal sorption in natural aquatic systems are seemingly at odds with physico-chemical adsorption theory: (1) characteristic sorption times of days to weeks and (2) Kds which are inversely related in magnitude to particle concentrations. In addition, sorption rate constants are positiveiy correlated with particle concentrations and Kd. This paper presents a conceptual and mathematical model with which it is proposed that these metal sorption characteristics have the same underlying physical process in common: the coagulation of colloidal (nonfilterable) particles onto larger (filterable) particles. “Brownian pumping” (the transfer of …


The Ventilated Thermocline In Quasigeostrophic Approximation, Myrl C. Hendershott Jan 1989

The Ventilated Thermocline In Quasigeostrophic Approximation, Myrl C. Hendershott

Journal of Marine Research

The ventilated thermocline model of Luyten et al. (hereafter LPS), (1983) is reformulated in the quasigeostrophic approximation. The quasigeostrophic solutions with zonal outcrop lines capture the salient features of the solutions of LPS. When the outcrop lines are sufficiently nonzonal, the quasigeostrophic solutions resemble those of Parsons (1969), Veronis (1973), and Huang (1984), resolving an inconsistency in Parsons' solution. But an attempt to close the quasigeostrophic solution having two moving layers with a western boundary current in which friction is parameterized as a linear drag coefficient results in an ill posed problem. The paper concludes with a comparison of cross-gyre …


A Nonlinear, Time-Dependent Thermocline Theory, William K. Dewar Jan 1989

A Nonlinear, Time-Dependent Thermocline Theory, William K. Dewar

Journal of Marine Research

A noneddy resolving, time-dependent, nonlinear theory of the large-scale ocean circulation is presented. The variability in this theory occurs as a response to variability in forcing. Baroclinic and barotropic evolution is computed using a two-layer, quasigeostrophic, wind-driven model. Both analytical and numerical solutions are obtained. Attention is focussed on the low-frequency, basin scale fluctuations of the wind. Based on these restrictions, the various modes of response are separated by means of a multiple time scale analysis. The barotropic response is found to be effectively instantaneous, and a relatively simple advection equation is shown to govern the baroclinic response. Analytical solutions …


Eddy Momentum And Heat Ftuxes And Their Effects On The Circulation Of The Equatorial Pacific Ocean, Harry L. Bryden, Esther C. Brady Jan 1989

Eddy Momentum And Heat Ftuxes And Their Effects On The Circulation Of The Equatorial Pacific Ocean, Harry L. Bryden, Esther C. Brady

Journal of Marine Research

Eddy momentum and heat fluxes are estimated from three-dimensional arrays of long time-series current meter measurements in the equatorial Pacific near 152W and 110W during 1979 to 1981. Eddies transport eastward momentum away from the equator above the core of the Equatorial Undercurrent; they transport eastward momentum toward the equator below the Undercurrent core. The vertical integral of the eddy momentum flux divergence is equivalent to a westward wind stress of 0.16 dyne cm–2. Eddies transport heat toward the equator at all depths down to 250 m. At 100 m depth and below, the eddy heat flux convergences …


Low Frequency Variability In The Lower St. Lawrence Estuary, Gordon Mertz, Mohammed I. El-Sabh, Vladimir G. Koutitonsky Jan 1989

Low Frequency Variability In The Lower St. Lawrence Estuary, Gordon Mertz, Mohammed I. El-Sabh, Vladimir G. Koutitonsky

Journal of Marine Research

The lower St. Lawrence Estuary is a good example of wide estuaries with a second lateral boundary within several internal Rossby radii. We compare direct measurements from the 1979 lower St. Lawrence estuary mesoscale current meter array with satellite thermal images observed during the same period. The current field appears to show two quasi-steady states: one configuration is characterized by strong outflow along the north shore of the estuary with a transverse front at the mouth. The other current pattern is more typical of estuaries, with inflow along the north shore and outflow along the south shore. Transitions between these …


On The Contribution Of The Benthos To Pelagic Production, Peter H. Doering Jan 1989

On The Contribution Of The Benthos To Pelagic Production, Peter H. Doering

Journal of Marine Research

Annual production and consumption of oxygen were compared in large outdoor mesocosms differing only in the presence or absence of an intact benthic community and associated sediments. Both daily apparent production and nighttime respiration of oxygen were greater in tanks with a benthos. The fluxes of oxygen into, and dissolved inorganic nitrogen out of the bottom were also greater in tanks with an intact benthos. In tanks with a benthos, calculated gross system production increased 33% relative to tanks lacking a benthos. Depending on assumed O:N ratios only 45–60% of this increase was attributable to differences in the flux of …


Chaetognaths And Oceanography On Georges Bank, R. Gregory Lough, Ronald W. Trites Jan 1989

Chaetognaths And Oceanography On Georges Bank, R. Gregory Lough, Ronald W. Trites

Journal of Marine Research

A dense breeding population of chaetognaths, Sagitta elegans, was observed on northeastern Georges Bank during autumn, 1978. Four grid surveys conducted on the northeast region of the Bank over the period 17-30 October 1978 revealed that the high concentration "patch" of adult S. elegans. about 56 km on long axis, remained essentially on the eastern part of the grid in weakly stratified water of 67 m average depth. Current meter measurements indicated residual flow to the southeast sufficiently high to transport a passively drifting organism out of the area over the two weeks of study. Discrete vertical sampling showed that …


A Numerical Study Of Wind Forcing Of Eddies And Jets In The California Current System, Mary L. Batteen, Robert L. Haney, Terrance A. Tielking, Philip G. Renaud Jan 1989

A Numerical Study Of Wind Forcing Of Eddies And Jets In The California Current System, Mary L. Batteen, Robert L. Haney, Terrance A. Tielking, Philip G. Renaud

Journal of Marine Research

A high-resolution, multi-level, primitive equation ocean model is used to examine the response to wind forcing of an idealized flat-bottomed oceanic regime along an eastern ocean boundary. A band of steady alongshore, upwelling favorable winds, either with or without alongshore variability, is used as forcing on both an f-plane and a, β-plane. In each experiment a wind-driven equatorward coastal jet and a poleward undercurrent are generated. In time the coastal jet and undercurrent become unstable and lead to the development of eddies and jets with relatively strong onshore and offshore directed flows. The alongshore variation in alongshore wind …


On The Barotropic Planetary Oscillations Of The Pacific, Arthur J. Miller Jan 1989

On The Barotropic Planetary Oscillations Of The Pacific, Arthur J. Miller

Journal of Marine Research

Free linear solutions of the barotropic shallow-water equations are computed for a variety of basin shapes and topographies relevant to the Pacific Ocean. Attention is drawn to the 2-day to 6-day period band within which large-scale coherency is observed in Pacific tide-gauge records of sea level. In a particular model basin with realistic topography, the fundamental planetary mode of the Pacific occurs with a period of 3 days and four other planetary-topographic modes populate the 4–6 day period band. We argue that the frequencies and structures of these modes are representative of the largest-scale vorticity oscillations of the Pacific and …


The Mythical Thermohaline Oscillator?, Barry Ruddick, Lingqi Zhang Jan 1989

The Mythical Thermohaline Oscillator?, Barry Ruddick, Lingqi Zhang

Journal of Marine Research

The system discussed by Stommel (1987) and Welander (1982), in which heating and evaporation at the surface of the ocean are balanced by vertical turbulent mixing, is studied analytically and numerically for mixing laws appropriate to salt fingers, rather than mechanical turbulence. Stommel and Welander found for mechanically-driven turbulent mixing that a limit cycle of T and S exists (that is, T and S oscillate) in the presence of steady forcing. We find that the usual salt finger parameterizations, in which salinity flux coefficient and buoyancy flux ratio decrease with increasing density ratio, do not allow a limit cycle. This …


Lead-210 And Polonium-210 In Pteropod And Heteropod Mollusc Shells From The North Pacific: Evaluation Of Sample Treatments And Variation With Shell Size, Victoria J. Fabry, Margaret L. Delaney Jan 1989

Lead-210 And Polonium-210 In Pteropod And Heteropod Mollusc Shells From The North Pacific: Evaluation Of Sample Treatments And Variation With Shell Size, Victoria J. Fabry, Margaret L. Delaney

Journal of Marine Research

Lead-210 activities in carefully cleaned size groups of pteropod and heteropod shells from the eastern equatorial Pacific were typically 0.3 dpm/g shell, similar to those reported in other biogenic calcium carbonates. However, 210Po activities were in excess of levels expected from the decay of shell-incorporated 210Pb, with (210Po/210Pb) activity ratios ranging from 20 to 28 in size-fractionated samples. Sample treatment procedures were examined using pteropod shells collected from diverse locations of the North Pacific. Possible sources of 210Po in excess of 210Pb in shells include inclusion of 210Po in the organic …


Mechanisms Of Subsurface Thermal Structure And Sea Surface Thermohaline Variabilities In The Southwestern Tropical Pacific During 1975-85, Thierry Delcroix, Christian Hénin Jan 1989

Mechanisms Of Subsurface Thermal Structure And Sea Surface Thermohaline Variabilities In The Southwestern Tropical Pacific During 1975-85, Thierry Delcroix, Christian Hénin

Journal of Marine Research

Major features of the southwestern tropical Pacific (SWTP), defined between 160E–140W and 24S–10S, are brought to light through analysis of surface water samples (23000) and temperature/depth observations (8500), both collected by ship of opportunity programs during the 1979–85 period. The mean vertical thermal structure (and its related parameters), mean sea surface temperature (SST) and salinity (SSS) are first portrayed, to further quantify the 1979–85 variability. It is demonstrated that the observed seasonal and interannual variabilities, the latter being associated with the strong 1982–83 EI Niño Southern Oscillation (ENSO) event, are mostly governed by specific mechanisms involving varying wind field and …


The Response Of The Coastal Ocean To Strong Offshore Winds: With Application To Circulations In The Gulfs Of Tehuantepec And Papagayo, Julian P. Mccreary Jr., Hyong S. Lee, David B. Enfield Jan 1989

The Response Of The Coastal Ocean To Strong Offshore Winds: With Application To Circulations In The Gulfs Of Tehuantepec And Papagayo, Julian P. Mccreary Jr., Hyong S. Lee, David B. Enfield

Journal of Marine Research

Two ocean models are used to investigate the response of the coastal ocean to strong offshore winds: a linear 1½-layer model, and a nonlinear 1½-layer model that allows entrainment of cool water into the surface layer. The models are forced by wind stress fields similar in structure to the intense winter-time, mountain-pass jets (∼20 dyne/cm2) that appear in the Gulfs of Tehuantepec and Papagayo for periods of 3–10 days. Solutions are arranged in a hierarchy of increasing dynamical complexity, in order to illustrate the important physical processes. They compare favorably with observations in several ways. Some properties of …


Longitudinal Dispersion Of Suspended Particles In Oscillatory Currents, Hidekazu Yasuda Jan 1989

Longitudinal Dispersion Of Suspended Particles In Oscillatory Currents, Hidekazu Yasuda

Journal of Marine Research

This study has investigated theoretically longitudinal dispersion of suspended fine particles with settling velocity and revealed the dispersing behavior from the initial to the stationary stages in tidal oscillatory currents. A Stokes layer of the oscillatory current plays a remarkably significant role on dispersion of settling particles when the mixing time in cross-section is larger than the period of tidal oscillation. When the settling velocity exceeds a certain value, however, the dispersion coefficient of particles decreases with increasing settling velocity. In an oscillatory current with linear profile, settling velocity of dispersing particles decreases the value of the dispersion coefficient all …


Microscale And Finescale Variations Of Small Plankton In Coastal And Pelagic Environments, R. W. Owen Jan 1989

Microscale And Finescale Variations Of Small Plankton In Coastal And Pelagic Environments, R. W. Owen

Journal of Marine Research

Small-interval water sampling in oceanic subsurface layers in a variety of macroenvironments for microplankton and for characteristics of their environment revealed concentration variations that often exceed errors of sampling and measurement. I report incidence and degree of microscale and finescale organism patchiness and their dependency on the local environment and on certain characteristics of the organisms themselves. Scale analysis indicates that patchiness occurs below as well as above the 20 cm intervals sampled. Incidence and degree of patchiness were about the same in separate eastern boundary regions, off California and Perú. Effects of environmental characteristics on organism patchiness are clearly …


Derivative Analysis Of Spectral Absorption By Photosynthetic Pigments In The Western Sargasso Sea, R. R. Bidigare, J. H. Morrow, D. A. Kiefer Jan 1989

Derivative Analysis Of Spectral Absorption By Photosynthetic Pigments In The Western Sargasso Sea, R. R. Bidigare, J. H. Morrow, D. A. Kiefer

Journal of Marine Research

Concurrent measurements of the spectral absorption coefficient and photosynthetic pigmentation of natural particulates were performed to determine the principal pigments responsible for the absorption of spectral irradiance in seawater. The spectral absorption coefficient, Ap(λ), was then analyzed by taking the second and fourth derivatives with respect to wavelength. The wavelength and magnitude of these derivative values provide useful information regarding the identification and quantification of phytoplankton pigments responsible for a given spectral signature. Linear relationships were examined and established between derivative values at selected wavelengths and concentrations of the major tetrapyrrole pigments, specifically chlorophylls a, b, and …


Wind-Driven Ocean Circulation And Equilibrium Statistical Mechanics, Annalisa Griffa, Rick Salmon Jan 1989

Wind-Driven Ocean Circulation And Equilibrium Statistical Mechanics, Annalisa Griffa, Rick Salmon

Journal of Marine Research

In this paper, we show that numerical solutions of the single-layer quasigeostrophic equation in a beta-plane basin approach the state predicted by equilibrium statistical mechanics when the forcing and dissipation are (unrealistically) zero. This equilibrium state, which we call Fofonoff flow, consists of a quasi-steady uniform westward interior flow closed by inertial boundary layers. When wind stress and bottom drag are switched on, we find that the nonlinear terms in the quasigeostrophic equation still try to drive the flow toward Fofonoff flow, but their success at this depends strongly on the geometry of the wind stress. If the prescribed wind …


On The Interaction Of Wind And Buoyancy Driven Gyres, Alain Colin De Verdière Jan 1989

On The Interaction Of Wind And Buoyancy Driven Gyres, Alain Colin De Verdière

Journal of Marine Research

The steady large scale oceanic response to wind stress and a surface buoyancy flux is studied by making use of a numerical model based upon the planetary geostrophic equations for which scales of motions smaller than the internal Rossby radius of deformation have been filtered out. In regions of both heat gain and Ekman convergence, the forcings combine to create a strong subtropical gyre in the upper thermocline. The north-south symmetry imposed by the wind pattern is broken because in a region of heat loss the density field shoals through the action of convection and the result is a broad …


Large-Scale Sst Anomalies Associated With Subtropical Fronts In The Western North Atlantic During Fasinex, George R. Halliwell Jr., Peter Cornillon Jan 1989

Large-Scale Sst Anomalies Associated With Subtropical Fronts In The Western North Atlantic During Fasinex, George R. Halliwell Jr., Peter Cornillon

Journal of Marine Research

We describe the large-scale variability of sea surface temperature (Ts) and fronts in the western North Atlantic Subtropical Convergence Zone from January–June 1986 within an approximately 11° longitude by 10° latitude domain. Fronts were primarily found within interconnected bands separated by <500 km that tended to be located on the periphery of anisotropic Ts spatial anomaly features that propagated westward at about 3 km day–1. Relatively weak and strong (small or large |∇Ts|) segments of the dominant zonally-oriented frontal band (the Subtropical Frontal Zone, or SFZ) shifted westward with these anomaly features, which had characteristic peak-to-peak space scales of up to ≈800 km …


Density Of The Major Size Groups Of Benthic Fauna And Trophic Input In Deep Basins Of The Atlantic Ocean, Myriam Sibuet, Claude E. Lambert, Roger Chesselet, Lucien Laubier Jan 1989

Density Of The Major Size Groups Of Benthic Fauna And Trophic Input In Deep Basins Of The Atlantic Ocean, Myriam Sibuet, Claude E. Lambert, Roger Chesselet, Lucien Laubier

Journal of Marine Research

Seven deep-sea areas were studied in the Atlantic Ocean. An intensive and comparable benthic sampling program was conducted during several deep-sea biology cruises with IFREMER research ships and mainly with the RV Jean Charcot, in the Norwegian Sea, the Bay of Biscay, the Porcupine Seabight, the Vema Fracture Zone, the Demerara abyssal plain, the Cape Verde Basin, the Angola and Cape basins near the Walvis Ridge. A synthesis of community structure data has been realized and the benthic fauna, quantitatively sampled, was separated into three main size categories (meiofauna, macrofauna sensu stricto and megafauna). Comparison of population densities in …


Maximal Quantum Yield Of Photosynthesis In The Northwestern Sargasso Sea, J. S. Cleveland, M. J. Perry, D. A. Kiefer, M. C. Talbot Jan 1989

Maximal Quantum Yield Of Photosynthesis In The Northwestern Sargasso Sea, J. S. Cleveland, M. J. Perry, D. A. Kiefer, M. C. Talbot

Journal of Marine Research

The magnitude and variability of the maximal quantum yield of photosynthesis were examined in the northwestern Sargasso Sea in April 1985. Maximal quantum yield was calculated from light-limited photosynthetic rates and spectrally-weighted absorption coefficients. The absorption by total particulates collected on a glass fiber filter was partitioned into two components, one associated with living phytoplankton and one associated with other absorbing particles. Two types of maximal quantum yield were calculated: one from the absorption by total particulates and one from the absorption by the phytoplanktonic component alone. Maximal quantum yield calculated from absorption by total particulates was low [0.014 to …


The Mode Site Revisited, William J. Schmitz Jr. Jan 1989

The Mode Site Revisited, William J. Schmitz Jr.

Journal of Marine Research

In the 1970's, an intense physical oceanographic effort was focused on the MODE Area (centered at 28N, 70W) to study mesoscale eddies and their effect on the larger-scale longer-term (or general) interior ocean circulation. At that time there was considerable discussion as to the typicality of these results. It has become clear that the time-dependent field is horizontally inhomogeneous; eddies have a geography related to the general circulation. In some areas, significant temporal inhomogeneity (nonstationarity) has been observed, but this issue has not yet been clarified for the MODE Area. Recently, a collective experiment to study the effect of fronts …


Interaction Of Internal Waves And Mean Flow Observed Near A Coast, Pijush K. Kundu, Richard E. Thomson, Barbara M. Hickey, Paul H. Leblond Jan 1988

Interaction Of Internal Waves And Mean Flow Observed Near A Coast, Pijush K. Kundu, Richard E. Thomson, Barbara M. Hickey, Paul H. Leblond

Journal of Marine Research

Vortex stretching has been proposed as a possible mechanism by which internal waves can extract energy from the mean flow. Relationships between the slowly varying (ω < 0.25 cpd) and rapidly varying (0.13 cph < ω < 0.5 cph) components of the flow have been examined in a 4-month-long data set taken off the coast of British Columbia. The rapidly varying component of horizontal velocity generally rotates clockwise, and is in rough agreement with internal wave dynamics. It is horizontally incoherent within a distance of 10 km and is vertically coherent across the water column with a nearly 180° phase change. Scatter plots show that the wavefield is anisotropic, with the Reynolds stresses generally obeying uv < 0, vw < 0 and uw > 0, where (u, v, w) are the fluctuating velocity components in the (onshore, alongshore, upward) directions. Instances have been found in which time variations of uv and the mean horizontal shear rate Vx are negatively correlated, with an implied horizontal viscosity of VH ∼ (3 ± 2) × 105 cm2/s. No correlation of vw and the mean vertical shear V …


A Numerical Model Study Of Internal Tides On The Australian Northwest Shelf, Peter D. Craig Jan 1988

A Numerical Model Study Of Internal Tides On The Australian Northwest Shelf, Peter D. Craig

Journal of Marine Research

Models of internal tides have been difficult to apply to realistic ocean situations because of restrictive assumptions on the form of either the bottom topography or the vertical density structure. A numerical model, based on the analytic model of Craig (1987a), is applied to a section through the Australian Northwest Shelf, and the results compared with data collected at the North Rankin location. The model simulates accurately the amplitude and phase structure of the internal tide. The predicted temperature and current amplitudes are within one-third of those observed, but the phase relationship between the temperature and surface tide is different …


Cross-Phyletic Patterns Of Particle Selection By Deposit Feeders, Robert F. L. Self, Peter A. Jumars Jan 1988

Cross-Phyletic Patterns Of Particle Selection By Deposit Feeders, Robert F. L. Self, Peter A. Jumars

Journal of Marine Research

In controlled laboratory experiments using a wide array of exotic sediments of known characteristics (glass and plastic beads) we studied the mechanical, evolutionarily-fixed component of particle selection for ingestion in 5 surface and 6 subsurface deposit feeders, from 3 phyla (Annelida, Mollusca and Arthropoda). Three species were nonselective within all or part of the 3-324 μm particle size range tested, while the remaining 8 species exhibited unimodal patterns of size selection, peaking near 6 μm. In addition, the surface deposit feeders displayed a strong preference for particles of low specific gravity. Particle selection in tube construction by the polychaetes …


On The Surface Drift Of The Southern Ocean, J. R. E. Lutjeharms, L. V. Shannon, L. J. Beekman Jan 1988

On The Surface Drift Of The Southern Ocean, J. R. E. Lutjeharms, L. V. Shannon, L. J. Beekman

Journal of Marine Research

Drift rates of the sea surface have been calculated for the South Atlantic and South Indian Ocean sectors of the Southern Ocean using drift cards and FGGE buoys. Drift patterns and drift rates, based on results from 40,000 plastic drift cards placed from 1978 to 1981, indicate significant equatorward surface exchange between the Southern Ocean and subtropical ocean gyres. Card drift rates increase with latitude up to the 40-45S zone. Average zonal drift rates lie between 10.3 cm/s and 16.4 cm/s. Zonally averaged drift rates of FGGE buoys are also at a maximum between 40 and 45S but are 15% …


Buoyancy Driven Planetary Flows, A. Colin De Verdière Jan 1988

Buoyancy Driven Planetary Flows, A. Colin De Verdière

Journal of Marine Research

The large scale flow patterns driven by surface buoyancy flux are obtained as numerical solutions of the planetary geostrophic equations to which dissipation and diffusion have been appended. Within a cartesian β plane, square box geometry, the solution is made of gyres of the largest possible size with western and northern intensification, anticyclonic above the main thermocline, cyclonic below. Within regions of heat gain, the classical equilibrium between downward eddy diffusion and vertical upwelling is approximately observed in the main thermocline. As a consequence the abyssal circulation (southern interior and western boundary current) behave according to the early Stommel-Arons' ideas. …


Recent Moored Current Meter And Sofar Float Observations In The Eastern Atlantic Near 32n, William J. Schmitz Jr., James F. Price, Philip L. Richardson Jan 1988

Recent Moored Current Meter And Sofar Float Observations In The Eastern Atlantic Near 32n, William J. Schmitz Jr., James F. Price, Philip L. Richardson

Journal of Marine Research

Basic flow statistics from the two-year deployment of a mooring in the vicinity of 32N and 24W are presented, along with intercomparisons between SOFAR float results concurrent with the first year of moored instrument data. Current-temperature meters were deployed in the main thermocline (∼500 m depth), in Mediterranean Water (1000–1100 m depth) along with the SOFAR floats, and at an abyssal (∼3000 m) level. The float and current meter averages over a common time interval are at least roughly the same, with eddy field intercomparisons being better than those for mean flow. Strong year-to-year variability in the time-averaged flow and …