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Henry Sears (1913–1982), George Veronis Jan 2009

Henry Sears (1913–1982), George Veronis

Journal of Marine Research

Henry Sears led a remarkably varied life centered on a love of sailing, racing and fishing. Even as a youngster he spent considerable time at sea because he had asthma and in those days sea air was considered beneficial for one with that ailment. He owned a Swampscott Dory at the age of eight and soon afterwards was sailing a 30-footer from Boston to the Maine coast. His education was unusual. It seems that he was dyslexic, although at the time of his birth dyslexia was not identified as such. During his childhood his family spent three months of the …

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Floral Patterns In The California Current: The Coastal-Offshore Boundary Zone, E. L. Venrick Jan 2009

Floral Patterns In The California Current: The Coastal-Offshore Boundary Zone, E. L. Venrick

Journal of Marine Research

This study quantified the vertical distributions of 294 taxa of phytoplankton from 112 samples in a vertical section across the California Current system off Southern California. The goal was to examine the relationship between coastal and offshore floras throughout the euphotic zone. The two associations were distinct throughout the upper 140 m. The coastal flora was found in water adjacent to and east of the Santa Rosa Ridge. The offshore flora occurred west of the California Current, and also at the station immediately east of the current, presumably the result of upstream entrainment across it. Both coastal and offshore floras …

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Rossby Wave Radiation From An Eastward Jet And Its Recirculations, Genta Mizuta Jan 2009

Rossby Wave Radiation From An Eastward Jet And Its Recirculations, Genta Mizuta

Journal of Marine Research

A series of numerical experiments is carried out to investigate in detail the properties of the variability radiated from a baroclinic jet and its recirculations. Driven by an inflow from the western boundary, an eastward jet and two recirculation gyres are formed in the statistically steady state. The variability of velocity away from the recirculation gyres is as strong as that near the jet at deeper depths, and the structure of this velocity variability was analysed by using the technique of Frequency-Domain Empirical Orthogonal Functions (FDEOFs). Motions represented by the first FDEOFs consist of the barotropic Rossby waves of various …

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Dynamics Of The Indonesian Seas Circulation. Part Ii – The Role Of Pressure Head, Vladimir M. Kamenkovich, Kieran T. A. O'Driscoll, Dmitri A. Nechaev Jan 2009

Dynamics Of The Indonesian Seas Circulation. Part Ii – The Role Of Pressure Head, Vladimir M. Kamenkovich, Kieran T. A. O'Driscoll, Dmitri A. Nechaev

Journal of Marine Research

The aim of this paper is to analyze the role of the pressure head, i.e., the difference of total pressure forces acting on the Indonesian seas waters from the western Pacific and the eastern Indian Ocean, in driving the Indonesian Throughflow (ITF) and in determining the total transport of the ITF. These questions have been discussed in the literature but no consensus has been reached. A regional model of the Indonesian seas circulation has been developed that properly resolves all major topographic features in the region. The results of model runs have been used to calculate all components of the …

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Winter Advection Of Iron Can Explain The Summer Phytoplankton Bloom That Extends 1000 Km Downstream Of The Kerguelen Plateau In The Southern Ocean, M. M. Mongin, E. R. Abraham, T. W. Trull Jan 2009

Winter Advection Of Iron Can Explain The Summer Phytoplankton Bloom That Extends 1000 Km Downstream Of The Kerguelen Plateau In The Southern Ocean, M. M. Mongin, E. R. Abraham, T. W. Trull

Journal of Marine Research

The predominantly low-chlorophyll conditions of the Southern Ocean are punctuated by regions of elevated phytoplankton biomass, including a bloom in the Antarctic Circumpolar Current (ACC) that extends for 1000 km downstream of the Kerguelen-Heard islands. Summer-time studies have demonstrated that iron from the islands and intervening shallow plateau (300–600 m) fuels localized production. Whether this supply, or alternatively iron brought to the surface by enhanced mixing in ACC eddies, drives the more extensive downstream bloom has not been addressed. We show that the extent and shape of the downstream bloom can be reproduced by simulating the winter-time spread of a …

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Deep Cyclogenesis By Synoptic Eddies Interacting With A Seamount, Andrew D. Greene, Georgi G. Sutyrin, D. Randolph Watts Jan 2009

Deep Cyclogenesis By Synoptic Eddies Interacting With A Seamount, Andrew D. Greene, Georgi G. Sutyrin, D. Randolph Watts

Journal of Marine Research

Strong deep eddies with cyclonic vorticity greater than 0.2 f0 were detected using an array of bottom current and pressure measurements in the Kuroshio Extension System Study (KESS) in 2004–2006. Daily maps showed these deep eddies developed locally. As in the Gulf Stream, meandering of the upper baroclinic jet generates deep cyclones and anticyclones by stretching and squashing the lower water column. However, unlike the Gulf Stream, the smaller vertical stretching and greater water depth in the Kuroshio Extension limits the relative vorticity generated by this vertical coupling process to about 0.1 f0. In the deep Kuroshio …

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Intermittent Layering In The Atlantic Equatorial Deep Jets, Claire Ménesguen, Bach Lien Hua, Mark D. Fruman, Richard Schopp Jan 2009

Intermittent Layering In The Atlantic Equatorial Deep Jets, Claire Ménesguen, Bach Lien Hua, Mark D. Fruman, Richard Schopp

Journal of Marine Research

Equatorial observations in the Atlantic show three distinct vertical scales: quasi-barotropic eastward Extra-Equatorial Jets (EEJ), Equatorial Deep Jets (EDJ) of scale 500–800 m, and a smaller scale signal (50–100 m) of thin layers of well-mixed tracer fields. In the combined system of jets, westward EDJ correspond to zero-Potential Vorticity (PV) "niches," inside of which most of the thin well-mixed layers are found. Because of its correlation with zero-PV niches, the formation of layers is interpreted as due to inertial instability. The latter encompasses inertial barotropic instability due to meridional shear (either steady or parametric), baroclinic symmetric instability due to sloping …

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Dynamics Of The Combined Extra-Equatorial And Equatorial Deep Jets In The Atlantic, Claire Ménesguen, Bach Lien Hua, Mark D. Fruman, Richard Schopp Jan 2009

Dynamics Of The Combined Extra-Equatorial And Equatorial Deep Jets In The Atlantic, Claire Ménesguen, Bach Lien Hua, Mark D. Fruman, Richard Schopp

Journal of Marine Research

The available meridional sections of zonal velocity with high vertical and meridional resolution reveal tall eastward jets at 2N and 2S, named the extra-equatorial jets (EEJ), straddling the stacked eastward and westward jets of smaller vertical scales right at the equator, the so-called equatorial deep jets (EDJ). In contrast to the semi-annual to interannual fluctuations in the zonal velocity component, the measured meridional velocity component is dominated by intraseasonal period. We argue here that the formation mechanism for both types of jets is linked to the intraseasonal variability in meridional velocity and the associated wave motions. A process study is …

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Deep Chlorophyll Maximum And Upper Ocean Structure Interactions: Case Of The Guinea Thermal Dome, Olaf Duteil, Alban Lazar, Yves Dandonneau, Ilana Wainer, Christophe Menkes Jan 2009

Deep Chlorophyll Maximum And Upper Ocean Structure Interactions: Case Of The Guinea Thermal Dome, Olaf Duteil, Alban Lazar, Yves Dandonneau, Ilana Wainer, Christophe Menkes

Journal of Marine Research

Deep Chlorophyll Maximum (DCM) modifies the upper ocean heat capture distribution and thus impacts water column temperature and stratification, as well as biogeochemical processes. This energetical role of the DCM is assessed using a 1 m-resolution 1D physical-biogeochemical model of the upper ocean, using climatological forcing conditions of the Guinea Dome (GD). This zone has been chosen among others because a strong and shallow DCM is present all year round. The results show that the DCM warms the seasonal thermocline by +2°C in September/October and causes an increase of heat transfer from below into the mixed layer (ML) by vertical …

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Perturbation Dynamics Of A Planktonic Ecosystem, Katherine Healey, Adam H. Monahan, Debby Ianson Jan 2009

Perturbation Dynamics Of A Planktonic Ecosystem, Katherine Healey, Adam H. Monahan, Debby Ianson

Journal of Marine Research

Planktonic ecosystems provide a key mechanism for the transfer of carbon from the atmosphere to the deep ocean via the so-called "biological pump." Mathematical models of these ecosystems have been used to predict CO2 uptake in surface waters at particular locations, and more recently have been embedded in global climate models. While the equilibrium properties of these models are well studied, less attention has been paid to their response to external perturbations, despite the fact that as a result of the variability of environmental forcing such ecosystems are rarely, if ever, in equilibrium. In this study, linear theory is …

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The Future Evolution Of The Southern Ocean Co2 Sink, Nicole S. Lovenduski, Takamitsu Ito Jan 2009

The Future Evolution Of The Southern Ocean Co2 Sink, Nicole S. Lovenduski, Takamitsu Ito

Journal of Marine Research

We investigate the impact of century-scale climate changes on the Southern Ocean CO2 sink using an idealized ocean general circulation and biogeochemical model. The simulations are executed under both constant and changing wind stress, freshwater fluxes, and atmospheric pCO2, so as to separately analyze changes in natural and anthropogenic CO2 fluxes under increasing wind stress and stratification. We find that the Southern Ocean sink for total contemporary CO2 is weaker under increased wind stress and stratification by 2100, relative to a control run with no change in physical forcing, although the results are sensitive …

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Evidence Of Infaunal Effects On Porewater Advection And Biogeochemistry In Permeable Sediments: A Proposed Infaunal Functional Group Framework, George G. Waldbusser, Roberta L. Marinelli Jan 2009

Evidence Of Infaunal Effects On Porewater Advection And Biogeochemistry In Permeable Sediments: A Proposed Infaunal Functional Group Framework, George G. Waldbusser, Roberta L. Marinelli

Journal of Marine Research

Bioturbating infauna significantly modify reaction and transport processes in permeable sediments, though most studies to date are limited in the scope of species examined. We conducted a comparative field study measuring density-dependent effects of six common bioturbating species on porewater advection and biogeochemistry, across three intertidal permeable sediment habitats. The species in this study are; head-down like deposit feeders (Abarenicola pacifica and Balanoglossus aurantiacus), surface deposit feeders (Diopatra cuprea and Onuphis jenneri) and gallery diffusers (Upogebia pugettensis and Neotrypaea californiensis). Tracer loss from gel diffusers was used to assess relative differences in porewater advection …

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The Skirted Island: The Effect Of Topography On The Flow Around Planetary Scale Islands, Joseph Pedlosky, Roberto Iacono, Ernesto Napolitano, Karl Helfrich Jan 2009

The Skirted Island: The Effect Of Topography On The Flow Around Planetary Scale Islands, Joseph Pedlosky, Roberto Iacono, Ernesto Napolitano, Karl Helfrich

Journal of Marine Research

The flow around planetary scale islands is examined when the island possesses a topographic skirt representing a steep continental shelf. The model is barotropic and governed by the shallow water equations and the motion is driven by a wind stress with a constant curl. The presence of the strong topographic "skirt" around the island vitiates the elegant Island Rule of Godfrey and the closed potential vorticity contours around the island produced by the topography allow a geostrophic, stationary mode to resonate with an amplitude that is limited only by dissipation. In the limit of weak forcing the outline of the …

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Asymmetries In Tidal Flow Over A Seto Inland Sea Scour Pit, Arnoldo Valle-Levinson, Xinyu Guo Jan 2009

Asymmetries In Tidal Flow Over A Seto Inland Sea Scour Pit, Arnoldo Valle-Levinson, Xinyu Guo

Journal of Marine Research

Underway profiles of current velocity were combined with stationary profiles of temperature and salinity around a vertically mixed scour pit of the Seto Inland Sea throughout a semidiurnal tidal cycle. This was done with the purpose of determining (a) whether flood flow is asymmetric relative to ebb over a pit with weakly stratified conditions, and (b) whether there is a dynamic transition from frictionally dominated tidal flow to advectively dominated tidal flow over the pit. These questions arose from previous studies elsewhere under stratified water columns, in contrast to the unstratified conditions at the study site. Observations showed an acceleration …

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Plankton Community Composition, Organic Carbon And Thorium-234 Particle Size Distributions, And Particle Export In The Sargasso Sea, H. S. Brew, S. B. Moran, M. W. Lomas, A. B. Burd Jan 2009

Plankton Community Composition, Organic Carbon And Thorium-234 Particle Size Distributions, And Particle Export In The Sargasso Sea, H. S. Brew, S. B. Moran, M. W. Lomas, A. B. Burd

Journal of Marine Research

Measurements of plankton community composition (eight planktonic groups), particle size-fractionated (10, 20, 53, 70, and 100-μm Nitex screens) distributions of organic carbon (OC) and 234Th, and particle export of OC and 234Th are reported over a seasonal cycle (2006–2007) from the Bermuda Atlantic Time-Series (BATS) site. Results indicate a convergence of the particle size distributions of OC and 234Th during the winter-spring bloom period (January–March, 2007). The observed convergence of these particle size distributions is directly correlated to the depth-integrated abundance of autotrophic pico-eukaryotes (r = 0.97, P < 0.05) and, to a lesser extent, Synechococcus (r = 0.85, P < 0.14). In addition, there are positive correlations between the sediment trap flux of OC and 234Th at 150 …

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New Observations Of The Spreading And Variability Of The Antarctic Intermediate Water In The Atlantic, Claudia Schmid, Silvia L. Garzoli Jan 2009

New Observations Of The Spreading And Variability Of The Antarctic Intermediate Water In The Atlantic, Claudia Schmid, Silvia L. Garzoli

Journal of Marine Research

The new and unique Argo data set currently available, in conjunction with other data previously collected, increases our understanding of the spreading of the Antarctic Intermediate Water in the southern and tropical Atlantic Ocean and to verify previous results. The combination of velocity and salinity data collected with Argo floats verified the main patterns of circulation at intermediate (800 to 1100 dbar) depths. Interesting new features in the pathways are found: (1) the existence of a new, third, branch of westward to northwestward flow that is fed by the Benguela Current; (2) two pathways through which the water from the …

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Intraseasonal Variability In The Makassar Strait Thermocline, Kandaga Pujiana, Arnold L. Gordon, Janet Sprintall, R. Dwi Susanto Jan 2009

Intraseasonal Variability In The Makassar Strait Thermocline, Kandaga Pujiana, Arnold L. Gordon, Janet Sprintall, R. Dwi Susanto

Journal of Marine Research

Intraseasonal variability [ISV] in the Makassar Strait thermocline is examined through the analysis of along-channel flow, regional sea level anomaly and wind fields from January 2004 through November 2006. The dominant variability of 45–90 day in the Makassar Strait along-channel flow is horizontally and vertically coherent and exhibits vertical energy propagation. The majority of the Makassar ISV is uncoupled to the energy exerted by the local atmospheric ISV: instead the Makassar ISV is due to the combination of a remotely forced baroclinic wave radiating from Lombok Strait and deep reaching ISV originating in the Sulawesi Sea. Thermocline depth changes associated …

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Temporal And Spatial Variation In Infaunal Community Structure In Physically Active Continental Shelf Sediments At A Long-Term Ecosystem Observatory (Leo-15) Off New Jersey, Usa, J. Frederick Grassle, Patricia A. Ramey, Rosemarie F. Petrecca Jan 2009

Temporal And Spatial Variation In Infaunal Community Structure In Physically Active Continental Shelf Sediments At A Long-Term Ecosystem Observatory (Leo-15) Off New Jersey, Usa, J. Frederick Grassle, Patricia A. Ramey, Rosemarie F. Petrecca

Journal of Marine Research

When the LEO-15 (Long-term Ecosystem Observatory at 15-m depth) research area was designated around Beach Haven Ridge (39°27.69′ N, 74°15.81′ W) in the early 1990's several stations were selected to reflect the different physical regimes and habitats present in a highly dynamic shelf environment. This study determined the composition, diversity, and abundance of infaunal communities at three contrasting stations on five dates in 1994–1995. A unique sampling scheme was used where a nested design was combined with targeted sampling by divers of benthic topographic habitat features, namely crests and troughs of sand ripples. The total number of taxa collected was …

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Mixing In Cyclonic Eddies In The Antarctic Circumpolar Current, Angela Hibbert, Harry Leach, Volker Strass, Boris Cisewski Jan 2009

Mixing In Cyclonic Eddies In The Antarctic Circumpolar Current, Angela Hibbert, Harry Leach, Volker Strass, Boris Cisewski

Journal of Marine Research

Observations over a period of 39 days of the increasing minimum core temperature of Winter Water trapped within a mature cyclonic eddy in the Antarctic Circumpolar Current encouraged us to assess the mixing processes which might lead to this temperature rise. Using diffusive heat budgets for alternatively diapycnic (∼vertical) and then isopycnic (∼horizontal) mixing combined with the observed rate of warming allowed upper limits for diapycnic and isopycnic diffusivities to be inferred. This gave values of (3.3 ± 0.8) × 10−4m2s−1 and 87 ± 20m2s−1 for the diapycnic and isopycnic diffusivities respectively. …

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On The Interannual Variability Of Nitrogen Fixation In The Subtropical Gyres, Fanny M. Monteiro, Michael J. Follows Jan 2009

On The Interannual Variability Of Nitrogen Fixation In The Subtropical Gyres, Fanny M. Monteiro, Michael J. Follows

Journal of Marine Research

Time-series observations of geochemical tracers and diazotroph abundances in the northern subtropical gyres suggest variability in nitrogen fixation on interannual and longer timescales. Using a highly idealized model of the biogeochemistry and ecology of a subtropical gyre, we explore the previously proposed hypothesis that such variability is regulated by an internal "biogeochemical oscillator." We find, in certain parameter regimes, self-sustained oscillations in nitrogen fixation, community structure and biogeochemical cycles even with perfectly steady physical forcing. During the oscillations of nitrogen fixation, "blooms" of diazotrophs occur at intervals between a year and several decades, consistent with the observed variability. The period …

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Dynamics Of The Indonesian Seas Circulation. Part I – The Influence Of Bottom Topography On Temperature And Salinity Distributions, Kieran T. A. O'Driscoll, Vladimir M. Kamenkovich Jan 2009

Dynamics Of The Indonesian Seas Circulation. Part I – The Influence Of Bottom Topography On Temperature And Salinity Distributions, Kieran T. A. O'Driscoll, Vladimir M. Kamenkovich

Journal of Marine Research

The influence of bottom topography on the distribution of temperature and salinity in the Indonesian seas region has been studied with a high-resolution model based on the Princeton Ocean Model. One of the distinctive properties of the model is an adequate reproduction of all major topographic features in the region by the model bottom relief. The three major routes of flow of Pacific water through the region have been identified. The western route follows the flow of North Pacific Water through the Sulawesi Sea, Makassar Strait, Flores Sea, and Banda Sea. This is the main branch of the Indonesian Throughflow. …

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Mass Transport In The Stokes Edge Wave, Jan Erik H. Weber, Peygham Ghaffari Jan 2009

Mass Transport In The Stokes Edge Wave, Jan Erik H. Weber, Peygham Ghaffari

Journal of Marine Research

The Lagrangian mass transport in the Stokes progressive edge wave is obtained from the vertically integrated equations of momentum and mass, correct to second order in wave steepness. The cross-shore momentum balance is between the mean pressure at the sloping bottom, the radiation stress, and the pressure gradient due to the mean surface slope. In the alongshore direction, the effect of viscosity leads to a wave attenuation, and hence a radiation stress component. The frictional effect on the mean Eulerian motion is modeled through a turbulent bottom drag. The alongshore momentum balance is between the mean pressure gradient due to …

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A Linear Diffusivity Model Of Near-Surface, Cross-Shore Particle Dispersion From A Numerical Simulation Of Central California’S Coastal Ocean, Patrick T. Drake, Christopher A. Edwards Jan 2009

A Linear Diffusivity Model Of Near-Surface, Cross-Shore Particle Dispersion From A Numerical Simulation Of Central California’S Coastal Ocean, Patrick T. Drake, Christopher A. Edwards

Journal of Marine Research

A simple diffusion model of cross-shore mixing employing an inhomogeneous diffusivity is applied to near-surface particle dispersion within a high-resolution numerical model of the central California coastal ocean. The theoretical model employs a linear diffusivity, Ky = νy, where y is the cross-shore coordinate and ν a constant, as traditionally assumed for wall-layer flows. A realistic implementation of the Regional Ocean Modeling System (ROMS) is used to generate hundreds of thousands of three-dimensional, passive particle trajectories. Particles were released daily along the inner shelf for one model year, 2002, tracked for 16 days and treated statistically as …

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Irminger Current Anticyclones In The Labrador Sea Observed In The Hydrographic Record, 1990 –2004, Tatiana Rykova, Fiammetta Straneo, Jonathan M. Lilly, Igor Yashayaev Jan 2009

Irminger Current Anticyclones In The Labrador Sea Observed In The Hydrographic Record, 1990 –2004, Tatiana Rykova, Fiammetta Straneo, Jonathan M. Lilly, Igor Yashayaev

Journal of Marine Research

A significant fraction of the lateral heat transport into the Labrador Sea's interior, needed to balance the net heat loss to the atmosphere, is attributed to the Irminger Current Anticyclones. These mesoscale eddies advect warm, salty boundary current water, of subtropical origin, from the boundary current to the interior— but when or how they release their anomalous heat content has not been previously investigated. In this study, we discuss the seasonal and interannual evolution of these anticyclones as inferred from the analysis of hydrographic data from the Labrador Sea from 1990 to 2004. The 29 identified anticyclones fall into two …

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Relative Dispersion In The Nordic Seas, I. Koszalka, J. H. Lacasce, K. A. Orvik Jan 2009

Relative Dispersion In The Nordic Seas, I. Koszalka, J. H. Lacasce, K. A. Orvik

Journal of Marine Research

We examine the relative dispersion of surface drifters deployed in the POLEWARD experiment in the Nordic Seas during 2007–2008. The drifters were launched in pairs and triplets, yielding 67 pairs with an initial separation of 2 km or less. There were 26 additional pairs from drifters which subsequently came near one another. As these produced statistically identical dispersion to the original pairs, we used them as well, yielding 93 pairs. The relative dispersion exhibits three phases. The first occurs during the first two days, at spatial scales less than 10 km. The dispersion increases approximately exponentially during this period, with …

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Effects Of Surface Forcing On The Seasonal Cycle Of The Eastern Equatorial Pacific, D. E. Harrison, A. M. Chiodi, G. A. Vecchi Jan 2009

Effects Of Surface Forcing On The Seasonal Cycle Of The Eastern Equatorial Pacific, D. E. Harrison, A. M. Chiodi, G. A. Vecchi

Journal of Marine Research

The roles of zonal and meridional wind stress and of surface heat flux in the seasonal cycle of sea surface temperature (SST) are examined with a primitive equation (PE) model of the tropical Pacific Ocean. While a variety of previous numerical and observational studies have examined the seasonal cycle of SST in the eastern tropical Pacific, it is noteworthy that different mechanisms have been invoked as primary in each case and different conclusions have been reached regarding the relative importance of the various components of surface forcing. Here, we perform a series of numerical experiments in which different components of …

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Salt Flux Into Coastal River Plumes: Dye Studies In The Delaware And Hudson River Outflows, R. W. Houghton, R. J. Chant, Ana Rice, Charles Tilburg Jan 2009

Salt Flux Into Coastal River Plumes: Dye Studies In The Delaware And Hudson River Outflows, R. W. Houghton, R. J. Chant, Ana Rice, Charles Tilburg

Journal of Marine Research

The results of ten dye tracer experiments conducted in 2003–2006 to study the dispersion of the outflow of the Delaware and Hudson Rivers are presented. A fluorescent dye tracer was used to track the river plume and to measure directly the salt flux into the plume. A variety of flow regimes were encountered. During strong upwelling events, a salt flux of ∼3 ÷ 10–4 kg m s–1 at the leading edge of the plume implies a vertical diffusivity of Kz ∼ 3 × 10–4 m–2 s–1. Comparable salt flux was measured at the …

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Measuring Turbulent Large-Eddy Structures With An Adcp. Part 2. Horizontal Velocity Variance, A. E. Gargett, A. E. Tejada-Martínez, C. E. Grosch Jan 2009

Measuring Turbulent Large-Eddy Structures With An Adcp. Part 2. Horizontal Velocity Variance, A. E. Gargett, A. E. Tejada-Martínez, C. E. Grosch

Journal of Marine Research

This paper considers the degree of accuracy with which observations from an acoustic Doppler current profiler (ADCP) can determine turbulent horizontal velocity variance. As in a previous paper addressing turbulent vertical velocity variance, we use a combination of techniques, deriving response functions from simple theory and from oceanic observations taken with a VADCP (an ADCP with an additional vertical (V) beam) in two different oceanic turbulent flows, Langmuir supercells (LSC) and unstable convection. In the case of LSC, we also determine response by sampling available Large-Eddy Simulations (LES) with specified beam geometry. In contrast with the previous investigation, where a …

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Sensitivity Of Plankton Biomass And Productivity To Variations In Physical Forcing And Biological Parameters In Chesapeake Bay, Ming Li, Liejun Zhong, Lawrence W. Harding Jr. Jan 2009

Sensitivity Of Plankton Biomass And Productivity To Variations In Physical Forcing And Biological Parameters In Chesapeake Bay, Ming Li, Liejun Zhong, Lawrence W. Harding Jr.

Journal of Marine Research

A coupled three-dimensional hydrodynamic-biogeochemical model is used to simulate plankton dynamics in Chesapeake Bay and examine its sensitivity to variations in biological parameters and physical forcing. The coupled biophysical model captures observed seasonal cycle and regional distributions of plankton in Chesapeake Bay and predicts the "phase lag" between the spring chlorophyll maximum and the summer primary productivity maximum. This lag traces to the delivery of dissolved inorganic nutrients in the winter-spring freshet from the Susquehanna River that fuels the spring bloom, whereas regenerated nutrients support high primary productivity in summer. The model shows that episodic wind events commonly associated with …

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A Shallow Water Model Conserving Energy And Potential Enstrophy In The Presence Of Boundaries, Rick Salmon Jan 2009

A Shallow Water Model Conserving Energy And Potential Enstrophy In The Presence Of Boundaries, Rick Salmon

Journal of Marine Research

We extend a previously developed method for constructing shallow water models that conserve energy and potential enstrophy to the case of flow bounded by rigid walls. This allows the method to be applied to ocean models. Our procedure splits the dynamics into a set of prognostic equations for variables (vorticity, divergence, and depth) chosen for their relation to the Casimir invariants of mass, circulation and potential enstrophy, and a set of diagnostic equations for variables that are the functional derivatives of the Hamiltonian with respect to the chosen prognostic variables. The form of the energy determines the form of the …

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