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Sources And Transport Of Suspended Calcites In Pacific Deep Water, J. C. Brun-Cottan, R. Auger, C. E. Lambert, R. Chesselet Jan 1991

Sources And Transport Of Suspended Calcites In Pacific Deep Water, J. C. Brun-Cottan, R. Auger, C. E. Lambert, R. Chesselet

Journal of Marine Research

Significantly large concentrations of suspended matter, especially calcites, are found at some locations in the Deep Pacific, particularly at the depth of the Pacific Benthic Thermocline. These particle-rich layers cannot be explained by simple classical settling processes nor by resuspension of the underlying sediment. A theoretical approach based on these data, on the hydrodynamic characteristics of the regional circulation and on some known physical and chemical parameters, leads us to postulate two possible mechanisms: the settling of large particles from surface waters and their preferential disaggregation at some specific depth, particularly at the Pacific Benthic Thermocline depth; or alternatively, the …

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Generation And Propagation Of Inertial Waves In The Subtropical Front, Dong-Ping Wang Jan 1991

Generation And Propagation Of Inertial Waves In The Subtropical Front, Dong-Ping Wang

Journal of Marine Research

A primitive-equation numerical model is used to examine the generation and propagation of internal-inertial waves in the Subtropical Front. The mesoscale variability in surface inertial currents is induced by radiation of internal-inertial waves out of the surface layer. On the warm side of the front, surface inertial energy is carried away by normal internal-inertial waves. A deep inertial energy maximum exists at the base of the thermocline where the effective local inertial frequency approaches the planetary inertial frequency. On the cold side of the front, the surface inertial energy is carried away by anomalously low frequency internal waves. A subsurface …

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Modeling Of Internal Tides In Fjords, V. Tverberg, B. Cushman-Roisin, H. Svendsen Jan 1991

Modeling Of Internal Tides In Fjords, V. Tverberg, B. Cushman-Roisin, H. Svendsen

Journal of Marine Research

A previous model for the distribution of internal tides above irregular topography is generalized to include arbitrary stratification and a radiation condition at the open boundary. Thanks to a small amount of dissipation, this model remains valid in the presence of resonant internal tides, leading to intense wave-energy beams. An application to a Norwegian fjord correctly reproduces the observed energy pattern consisting of two beams both originating at the 60-meter deep entrance sill and extending in-fjord, one upward toward the surface, the other downward toward the bottom. After correction for the varying width of the fjord, the observed and modelled …

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Modeling The Variability Of The Somali Current, D. L. T. Anderson, D. J. Carrington, R. Corry, C. Gordon Jan 1991

Modeling The Variability Of The Somali Current, D. L. T. Anderson, D. J. Carrington, R. Corry, C. Gordon

Journal of Marine Research

The dynamics of the Somali Current system during the southwest Monsoon are investigated using a 16 level general circulation model. Solutions are found for a number of model geometries and wind-forcing patterns. The first integrations reported use a model domain exactly equivalent to that of the layer model of McCreary and Kundu allowing a direct comparison between the level and layer models. In the second set of integrations a more realistic Indian Ocean geometry is used, but still with an idealized wind forcing, while in the third, the Hellerman and Rosenstein wind stresses are used to simulate the seasonal cycle. …

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On The Structure And Stability Of The Alaskan Stream, R. K. Reed, F. I. Gonzalez, L. Miller Jan 1991

On The Structure And Stability Of The Alaskan Stream, R. K. Reed, F. I. Gonzalez, L. Miller

Journal of Marine Research

Data from a year-long current mooring in the central region of the Alaskan Stream revealed an extremely stable flow unlike that in typical western boundary currents. Hydrographic and ADCP data also showed a simple flow free of excursions or eddies. These findings are in good agreement with a recent analytical model of the Stream. In addition, GEOSAT altimeter estimates of variability are consistent with the observations, suggesting that the results are valid in spite of the relatively large corrections applied at these high latitudes.

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Control Of Deep-Sea Benthic Community Structure By Oxygen And Organic-Matter Gradients In The Eastern Pacific Ocean, Lisa A. Levin, Cynthia L. Huggett, Karen F. Wishner Jan 1991

Control Of Deep-Sea Benthic Community Structure By Oxygen And Organic-Matter Gradients In The Eastern Pacific Ocean, Lisa A. Levin, Cynthia L. Huggett, Karen F. Wishner

Journal of Marine Research

At boundaries of oxygen minimum zones (OMZs), bathyal faunas experience steep gradients in oxygen and organic-matter availability. The present study compares changes in microbial, meiofaunal, macrofaunal and megafaunal benthic assemblages along these gradients on Volcano 7, a 2.3-km high seamount in the eastern tropical Pacific. Faunal tolerance to dysaerobic (low oxygen) conditions varies with organism size; microbial and meiofaunal abundances are less affected than macro- and megafaunal abundances. At the exceedingly low concentrations (<0.1 ml/l) encountered on the upper summit of Volcano 7, oxygen appears to exert primary control over abundance, composition and diversity of macrofauna, overriding other factors such as food availability and sediment grain size. When oxygen concentration is sufficient, food availability in sediments (indicated by the presence of labile material such as chlorophyll a) is highly correlated with meiofaunal and macrofaunal abundance. Four distinct physical zones were identified on Volcano 7: (1) the coarse-grained upper summit zone (730–770 …

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The Climatological Seasonal Circulation Of The Mediterranean Sea, Eli Tziperman, Paola Malanotte-Rizzoli Jan 1991

The Climatological Seasonal Circulation Of The Mediterranean Sea, Eli Tziperman, Paola Malanotte-Rizzoli

Journal of Marine Research

The horizontal circulation of the upper 800 m of the Mediterranean Sea is calculated from a seasonal climatological hydrographic data set using a simple inverse model. The results show a fairly steady surface circulation in the western Mediterranean and a somewhat stronger seasonal signal in the surface circulation of the eastern Mediterranean. The deep flow field can be calculated for most of the Mediterranean, except for the Levantine basin east of Crete, where the high noise level in the data masks the deep circulation. The calculated deep velocity field (below 500 m) shows some interesting features, including several steady cyclonic …

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A Carbon Budget For A Eutrophic Marine Ecosystem And The Role Of Sulfur Metabolism In Sedimentary Carbon, Oxygen And Energy Dynamics, P. Sampou, C. A. Oviatt Jan 1991

A Carbon Budget For A Eutrophic Marine Ecosystem And The Role Of Sulfur Metabolism In Sedimentary Carbon, Oxygen And Energy Dynamics, P. Sampou, C. A. Oviatt

Journal of Marine Research

Organic carbon was budgeted for an experimental marine ecosystem which received 21.2 mol C m–2 of allochthonous sewage sludge plus 12.4 mol C m–2 in situ net daytime production over a 99 day experiment. The fate of carbon, in order of importance, was remineralization, storage in the sediments and export. Sediment carbon metabolism was dominated by sulfate reduction which resulted in the dissociation of organic carbon remineralization from oxygen consumption and energy cycling. The sediments were inefficient in processing sedimented carbon and its associated chemical energy. About 70% of the energy reaching the sediments as organic carbon remained …

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Expatriation Of Xyrichtys Novacula (Pisces: Labridae) Larvae: Evidence Of Rapid Cross-Slope Exchange, Jonathan A. Hare, Robert K. Cowen Jan 1991

Expatriation Of Xyrichtys Novacula (Pisces: Labridae) Larvae: Evidence Of Rapid Cross-Slope Exchange, Jonathan A. Hare, Robert K. Cowen

Journal of Marine Research

Larvae of Xyrichtys novacula (Pisces: Labridae) have been collected in the Middle Atlantic Bight (MAB) hundreds of kilometers north of reported adult ranges by both the Marine Monitoring and Assessment Program (MARMAP) and by our ichthyoplankton cruises. These larvae could be from a previously unknown population north of Cape Hatteras or they could have been transported north from southern populations. In order to examine these two hypotheses both biological and physical oceanographic data were considered, including size-specific larval distribution, larval age, vertical distribution of larvae, satellite imagery of sea surface temperature, and temperature and salinity measurements. Larvae captured during our …

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The Kinetics Of Organic Matter Mineralization In Anoxic Marine Sediments, David J. Burdige Jan 1991

The Kinetics Of Organic Matter Mineralization In Anoxic Marine Sediments, David J. Burdige

Journal of Marine Research

The kinetics of sulfate reduction and inorganic nutrient production (ΣCO2, ammonium, and phosphate) were examined in the sediments at five sites in the southern Chesapeake Bay, using long term (> 200 d) sediment decomposition experiments. Average first order rate constants for these processes (at 25°C) decreased from 8.2 to 3.7 yr–1 in the surface sediments (0–2 cm), to 2.1 to 0.2 yr–1 at 12–14 cm. The C/N and C/P ratios of the organic matter undergoing decomposition also increased with depth at these sites. Taken together, these results indicate that the reactivity of the organic matter undergoing …

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Laminar Separation Of Colliding Western Boundary Currents, Paola Cessi Jan 1991

Laminar Separation Of Colliding Western Boundary Currents, Paola Cessi

Journal of Marine Research

A barotropic model is employed to study the dynamics of colliding jets along a western boundary. To isolate the processes at the western wall we use a regional model where two opposing jets are induced by prescribing narrow inflows at the northern and southern edges of the computational domain. The fluid is withdrawn from the domain on the eastern side.

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Arrested Fronts, William K. Dewar Jan 1991

Arrested Fronts, William K. Dewar

Journal of Marine Research

A theory of fronts within the general circulation is discussed. These fronts and their associated jets differ from the more classical picture of boundary jets and their extensions (an example being the Gulf Stream system) in that they occur in the interior of the general circulation. The mechanism at the heart of the frontogenesis is nonlinear beta steepening, which arises from geostrophy in the presence of continuity. Such dynamics have been used in the past in a study of planetary shock waves. It is here argued that these dynamics result in stationary shock fronts in the general circulation. An equation …

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Tidal Stirring And Phytoplankton Bloom Dynamics In An Estuary, James E. Cloern Jan 1991

Tidal Stirring And Phytoplankton Bloom Dynamics In An Estuary, James E. Cloern

Journal of Marine Research

A decade of observation in South San Francisco Bay demonstrates that estuarine phytoplankton biomass fluctuates at the time scale of days to weeks, and that much of this variability is associated with fluctuations in tidal energy. During the spring seasons of every year from 1980–1990, episodic blooms occurred in which phytoplankton biomass rose from a baseline of 2–4 mg chlorophyll a m–3, peaked at 20–40 mg chlorophyll a m–3, and then returned to baseline values, all within several weeks. Each episode of biomass increase occurred during neap tides, and each bloom decline coincided with spring tides. …

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The Effect Of East River On The Barotropic Motions In Long Island Sound, Kuo-Chuin Wong Jan 1991

The Effect Of East River On The Barotropic Motions In Long Island Sound, Kuo-Chuin Wong

Journal of Marine Research

A linearized, frequency-dependent analytical model is developed to examine the effect of East River on the barotropic motions in Long Island Sound. At tidal frequencies, East River creates a slightly imperfect reflecting wall at the western end of Long Island Sound, resulting in moderate reduction in the resonance of the M2 tide. At subtidal frequencies the presence of East River permits a significant amount of volume exchange through the western end of Long Island Sound, causing large scale adjustments in both the amplitude and the phase of the barotropic flow well into the interior of the Sound. It appears …

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A Subsurface Cyclonic Eddy In The Bay Of Bengal, M. T. Babu, Prasanna Kumar, D. P. Rao Jan 1991

A Subsurface Cyclonic Eddy In The Bay Of Bengal, M. T. Babu, Prasanna Kumar, D. P. Rao

Journal of Marine Research

CTD data collected from the northwestern Bay of Bengal during late July 1984 reveal the existence of a cold core subsurface eddy centered at 17°40'N and 85°19'E. The thermal structure observed across the eddy indicates that it was confined to a level well below the mixed layer, between 50 and 300 db, and that it had a diameter of about 200 km. A temperature drop of 4–5°C as compared with the surroundings was observed at the center of the eddy. A plausible mechanism for the eddy generation is baroclinic instability at the interface of two opposing boundary currents present along …

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The Influence Of A Changing Bacterial Community On Trace Metal Scavenging In A Deep-Sea Particle Plume, James P. Cowen, Yuan Hui Lui Jan 1991

The Influence Of A Changing Bacterial Community On Trace Metal Scavenging In A Deep-Sea Particle Plume, James P. Cowen, Yuan Hui Lui

Journal of Marine Research

An extensive set of particle samples was collected from the extended (nonbuoyant) hydrothermal plume, the distal remnant plume, and the adjacent waters in a transect across the Southern Juan de Fuca Ridge. Bacterial capsules comprised the primary species of particulate Mn. However, the data also showed significant shifts in the relative abundance of distinctive subpopulations of this bacterial community, as expressed by several consistently recurring capsule morphologies. The data are discussed with respect to distance from plume origins (relative plume age), total bacterial numbers, experimentally determined scavenging rate constants and total particulate and dissolved Mn. The relative distribution of one …

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Diel Migration And Feeding Patterns Of The Chaetognath, Sagitta Friderici, Off The West Coast Of South Africa, Venetia Stuart, Hans M. Verheye Jan 1991

Diel Migration And Feeding Patterns Of The Chaetognath, Sagitta Friderici, Off The West Coast Of South Africa, Venetia Stuart, Hans M. Verheye

Journal of Marine Research

The vertical distribution patterns of adult and juvenile Sagitta friderici were investigated over a 48 h period, using samples collected at different depth strata with an RMT 1 × 6 net. Juvenile chaetognaths were generally found at depths of less than 50 m throughout the day and night, and exhibited limited diel migration patterns. Adults, on the other hand, migrated more extensively and were generally found below 50 m during the day and scattered throughout the water column or near the surface at night. Using the mean depths at each sampling time, the migration patterns of adult chaetognaths closely followed …

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Nonlinear General Circulation Of An Ocean Model Driven By Wind With A Stochastic Component, Annalisa Griffa, Sergio Castellari Jan 1991

Nonlinear General Circulation Of An Ocean Model Driven By Wind With A Stochastic Component, Annalisa Griffa, Sergio Castellari

Journal of Marine Research

The effects of the stochastic component of the large-scale wind on the climatological mean of the nonlinear ocean circulation are studied, using a set of numerical solutions for the single-layer, quasi-geostrophic equation in a closed basin with a flat bottom. In the absence of a steady wind, the purely stochastic wind is found to drive the solutions toward a nonlinear mean flow similar to that of the free system (i.e. without forcing and dissipation). This equilibrium mean flow (Fofonoff flow), is predicted by statistical mechanics and is characterized by a westward interior closed by inertial boundary layers along the coast. …

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Micropatchiness, Turbulence And Recruitment In Plankton, Cabell S. Davis, Glenn R. Flierl, P. H. Wiebe, P. J. S. Franks Jan 1991

Micropatchiness, Turbulence And Recruitment In Plankton, Cabell S. Davis, Glenn R. Flierl, P. H. Wiebe, P. J. S. Franks

Journal of Marine Research

A series of models are presented which examine the relative importance of microscale patchiness and turbulence to growth and recruitment in planktonic consumers. The analyses apply over scales from centimeters to meters (e.g. from copepods to fish larvae), and we assume food-limited conditions, since, otherwise, patchiness would not affect growth. A model of individual growth response to fluctuating food is developed which shows that growth is approximately exponential and is linearly related to food concentration. A random walk model reveals that the swimming process can be approximated as a simple diffusion term which, when included in the exponential growth model, …

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Similarity Solutions Of The Thermocline Equations, Rick Salmon, Rainer Hollerbach Jan 1991

Similarity Solutions Of The Thermocline Equations, Rick Salmon, Rainer Hollerbach

Journal of Marine Research

We apply symmetry group methods to find the group of transformations of the dependent and independent variables that leave the thermocline equations unchanged, These transformations lead to an optimal subset of sixteen forms of similarity solution, Each form obeys an equation with one fewer dependent variable than the original thermocline equations. Previously obtained similarity solutions, which are based solely upon scaling symmetries, are special cases of just three of these forms. Two of the sixteen forms lead to linear, two-dimensional, advection-diffusion equations for the temperature, Bernoulli functional or potential vorticity. Simple exact solutions contain "internal boundary layers" that resemble the …

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The Effects Of Flow Disturbance By An Oceanic Island, Karen J. Heywood, Eric D. Barton, John H. Simpson Jan 1990

The Effects Of Flow Disturbance By An Oceanic Island, Karen J. Heywood, Eric D. Barton, John H. Simpson

Journal of Marine Research

We present CTD and ADCP surveys around the Indian Ocean coral atolls of Aldabra (46°20′E, 9°25′S) and Cosmoledo (47°30E, 9°45′S) during April–July 1987. These isolated, steep-sided islands situated in deep (4000 m) water in the South Equatorial Current provide examples of flow disturbance which are compared to laboratory studies of eddy generation by a circular cylinder in a channel. For sufficiently strong and steady flows, a doming of the isopycnals is observed in the lee of the islands. The sea-surface temperature decreases and the salinity increases as cool, saline water is mixed from below. Just as in the case of …

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Δ14c Balance For The Gulf Of Maine, Long Island Sound And The Northern Middle Atlantic Bight: Evidence For The Extent Of The Antarctic Intermediate Water Contribution, N. Tanaka, M. C. Monaghan, K. K. Turekian Jan 1990

Δ14c Balance For The Gulf Of Maine, Long Island Sound And The Northern Middle Atlantic Bight: Evidence For The Extent Of The Antarctic Intermediate Water Contribution, N. Tanaka, M. C. Monaghan, K. K. Turekian

Journal of Marine Research

The radiocarbon signatures of the western Sargasso Sea and the atmosphere as a function of time over the past 200 years are known. These can be combined with seawater dissolved inorganic carbon (DIC) radiocarbon data from the Gulf of Maine and the northern Middle Atlantic Bight (MAB), including Long Island Sound (LIS), for 1983 and pre-1955 shell analyses for radiocarbon, to set the amount of Antarctic Intermediate Water (AAIW) required to balance the 14C budget in the northern MAB. Approximately 40% of the water entering the Middle Atlantic Bight from the north must be AAIW, the other 60% being …

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Barotropic Variability In The Presence Of An Ocean Gyre, Richard J. Greatbatch, Jin Li Jan 1990

Barotropic Variability In The Presence Of An Ocean Gyre, Richard J. Greatbatch, Jin Li

Journal of Marine Research

We describe results from some idealized numerical calculations in which we examine the influence of a barotropically stable mean flow on wind-driven variability in a flat-bottomed barotropic vorticity equation model. The mean flow has features in common with the vertically integrated time-mean circulation found in eddy-resolving models with a Sverdrup interior, western boundary current and inertial recirculation region. We integrate the equations of motion linearized about this flow and driven by oscillating wind forcing and compare the results with those obtained when the mean state is one of rest. We find that the presence of a mean flow leads to …

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The North Atlantic Current And Subarctic Intermediate Water, Michel Arhan Jan 1990

The North Atlantic Current And Subarctic Intermediate Water, Michel Arhan

Journal of Marine Research

The region where the North Atlantic Current crosses the ocean around 50N is studied from a watermass point of view and using the ventilated thermocline model of Luyten et al. (1983). Both approaches focus on the part played by the Subarctic Intermediate Water which, owing to its pronounced thermohaline anomalies stands out as a clue to the complex oceanic circulation in this area. Vertical mixing of this watermass with the overlying North Atlantic Central Water creates a fresher variety of central water found between the two major branches of the North Atlantic Current. Using the ventilated thermocline model several …

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Optical Efficiency Factors Of Free-Living Marine Bacteria: Influence Of Bacterioplankton Upon The Optical Properties And Particulate Organic Carbon In Oceanic Waters, André Morel, Yu-Hwan Ahn Jan 1990

Optical Efficiency Factors Of Free-Living Marine Bacteria: Influence Of Bacterioplankton Upon The Optical Properties And Particulate Organic Carbon In Oceanic Waters, André Morel, Yu-Hwan Ahn

Journal of Marine Research

Free-living coccoid bacteria have been repeatedly isolated from the Mediterranean Sea and then cultured in detritus- and predator-free seawater, either unenriched or slightly nutrient-supplemented. The modal diameter of these cultured cells was in the 0.5 to 1 μm range. The spectral values (within the 400–750 nm λ-range) of absorption, total scattering and backscattering have been determined, together with cell enumeration, size distribution and C–N content. Because of their smallness, bacteria are amenable to simplified theoretical expressions providing their optical efficiency factors. Experimental data are in remarkable quantitative agreement with theoretical predictions. As expected, scattering is wavelength (λ−2) …

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A Mechanistic View Of The Particulate Biodiffusion Coefficient: Step Lengths, Rest Periods And Transport Directions, R. A. Wheatcroft, P. A. Jumars, C. R. Smith, A. R. M. Nowell Jan 1990

A Mechanistic View Of The Particulate Biodiffusion Coefficient: Step Lengths, Rest Periods And Transport Directions, R. A. Wheatcroft, P. A. Jumars, C. R. Smith, A. R. M. Nowell

Journal of Marine Research

We link specific mechanisms of biogenous sediment mixing with the commonly used bioturbation coefficient (Db) that describes their bulk effects. Using an isotropic, stationary, unbiased random walk model we mechanistically decompose the particulate bioturbation coefficient into the fundamental dimensions of length and time. The result shows that Db depends directly on the square of the distance particles are moved (step length) and inversely on the elapsed time between movements (rest period). This new decomposition in terms of explicit mechanisms (i.e., animal activities), leads to scaling arguments that large, deposit feeding animals will in nearly all cases …

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On The Influence Of The Continental Slope On The Western Boundary Layer: The Enhanced Transport And Recirculation, Zhengyu Liu Jan 1990

On The Influence Of The Continental Slope On The Western Boundary Layer: The Enhanced Transport And Recirculation, Zhengyu Liu

Journal of Marine Research

Quasi-geostrophic theory is used to study the effect of a continental slope on the Western Boundary Layer. The compression of the vortex tubes by the slope results in a strong northward boundary current called the Continental Slope Boundary Current (hereafter CSBC). On the β-plane, for a reasonably high slope, we find a strong barotropic recirculation which enhances the total transport of the Western Boundary Current significantly. The two-layer model further shows that the CSBC is trapped in the lower layer. In oceans with very deep lower layers, the CSBC transport increases dramatically. Consequently, even for a very weak lower layer …

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Hydrography And Circulation Off The West Coast Of India During The Southwest Monsoon 1987, S. R. Shetye, A. D. Gouveia, S. S. C. Shenoi, D. Sundar, G. S. Michael, A. M. Almeida, K. Santanam Jan 1990

Hydrography And Circulation Off The West Coast Of India During The Southwest Monsoon 1987, S. R. Shetye, A. D. Gouveia, S. S. C. Shenoi, D. Sundar, G. S. Michael, A. M. Almeida, K. Santanam

Journal of Marine Research

During June–August 1987 thirteen hydrographic sections, each approximately perpendicular to the coast, covered the coastal region off western India. The southernmost section showed occurrence of upwelling, the nearshore surface temperature being about 2.5°C lower than farther offshore. There was a shallow (approximately 75 to 100 m deep) equatorward surface current, below which there were signatures of downwelling indicative of a poleward undercurrent hugging the continental slope. T-S characteristics showed that the undercurrent carried low salinity water found in the southwestern Bay of Bengal. Conditions similar to those found at this section existed up to around 15N but the intensity of …

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Early Diagenesis And Recycling Of Biogenic Debris At The Seafloor, Santa Monica Basin, California, Richard A. Jahnke Jan 1990

Early Diagenesis And Recycling Of Biogenic Debris At The Seafloor, Santa Monica Basin, California, Richard A. Jahnke

Journal of Marine Research

Seafloor recycling of organic materials in Santa Monica Basin, California was examined through in situ benthic chamber experiments, shipboard whole-core incubations and pore water studies. Mass balance calculations indicate that the data are internally consistent and that the estimated benthic exchange rates compare well with those derived from deep, moored conical sediment traps and hydrographic modeling. Pore water and benthic flux observations indicate that the metabolizable organic matter at the seafloor must be composed of at least two fractions of very different reactivities. While the majority of reactive organic compounds degrade quickly, with a half-life of <6.5 years, ¼ of the total metabolizable organic matter appears to react more slowly, with a half-life on the order of 1700 years. Down-core changes in pore water sulfate and titration alkalinity are not explained by stoichiometric models of organic matter diagenesis and suggest that reactions not considered previously must be influencing the pore water concentrations. Measured recycling and burial rates indicate that 43% of the organic carbon reaching the basin seafloor is permanently buried. The results for Santa Monica Basin are compared to those reported for other California Borderland Basins that differ in sedimentation rate and bottom water oxygen content. Organic carbon burial rates for the Borderland Basins are strongly correlated with total organic carbon deposition rate and bulk sedimentation rate. No significant correlation is observed between carbon burial and bottom water oxygen, extent of oxic mineralization and sediment mixing. Thus, for the California Borderlands, it appears that carbon burial rates are primarily controlled by input rates and not by variations in preservation.

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The Mixed-Layer Climatology In The Northwestern Part Of The North Pacific Subtropical Gyre And The Formation Area Of Subtropical Mode Wate, Toshio Suga, Kimio Hanawa Jan 1990

The Mixed-Layer Climatology In The Northwestern Part Of The North Pacific Subtropical Gyre And The Formation Area Of Subtropical Mode Wate, Toshio Suga, Kimio Hanawa

Journal of Marine Research

Climatological character of the mixed layer in the northwestern part of the subtropical North Pacific and the formation area of Subtropical Mode Water (STMW) are investigated using all available hydrographic data compiled by the Japan Oceanographic Data Center. Various monthly mean properties of the mixed layer averaged over 2° × 5° (lat. × lon.) rectangles are presented. In the heating season, the mixed layer is less thick throughout the region, while in the cooling season, a prominent thick mixed layer whose properties correspond with those of STMW evolves just off the Kuroshio both south and east of Japan. This probable …

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