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Articles 2221 - 2250 of 2279

Full-Text Articles in Life Sciences

15N/14N And 13C/12C In Weddell Sea Birds, Seals, And Fish: Implications For Diet And Trophic Structure, Greg H. Rau, David G. Ainley, John L. Bengston, Joseph J. Torres, Thomas L. Hopkins Jul 1992

15N/14N And 13C/12C In Weddell Sea Birds, Seals, And Fish: Implications For Diet And Trophic Structure, Greg H. Rau, David G. Ainley, John L. Bengston, Joseph J. Torres, Thomas L. Hopkins

Marine Science Faculty Publications

delta-C-13, delta-N-15, and C/N were measured for each of 247 muscle tissue samples from 12 bird, 4 seal, and 4 fish species collected in the Weddell Sea primarily during March 1986. delta-C-13 values ranged from -31.3 to -22.0 parts per thousand and, in the case of fish and seal samples, varied inversely with C/N. This implied that lipid concentration significantly influenced these vertebrate delta-C-13 measurements. No such relationship was found between C/N and delta-N-15, where the latter values ranged from +4.4 to +11.2 parts per thousand. with considerable overlap among many of the taxonomic groups measured. Notable exceptions to this …

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The 26‐Day Oscillation Observed In The Satellite Sea Surface Temperature Measurements In The Equatorial Western Indian Ocean, Pedro T. H. Tsai, James J. O'Brien, Mark E. Luther Jun 1992

The 26‐Day Oscillation Observed In The Satellite Sea Surface Temperature Measurements In The Equatorial Western Indian Ocean, Pedro T. H. Tsai, James J. O'Brien, Mark E. Luther

Marine Science Faculty Publications

A 26‐day oscillation in sea surface temperature (SST) data is observed in the western Indian Ocean, from 52° to 60°E and in the vicinity of the equator. The SST data used in this study are obtained from the NOAA 9 satellite and are for the years 1987 and 1988. This fluctuation of SST at a period near 26 days is found to be antisymmetric about the equator and is trapped within the equatorial waveguide (equator ±6°). The variance associated with this oscillation has a maximum located at about 3° latitude; furthermore, the variance decreases at a faster rate toward the …

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Nutrient Provinces In The Sea: Concentration Ratios, Reaction Rate Ratios, And Ideal Covariation, Kent A. Fanning Apr 1992

Nutrient Provinces In The Sea: Concentration Ratios, Reaction Rate Ratios, And Ideal Covariation, Kent A. Fanning

Marine Science Faculty Publications

Global distributions of the ratios of the concentrations of nitrate + nitrite (= [N]) and phosphate (= [P]) are evaluated from Geochemical Ocean Sections Study (GEOSECS) and Transient Tracers in the Ocean (TTO) data sets. If large oceanic regions (or provinces) can be identified on the basis of constant [N]:[P] ratios, then the distribution equation for a reactive variable shows that the ratio of the net reaction rates involving N and P in each one is equal to its concentration ratio. Organisms within the interiors of the provinces would then be in balance with the ratios in which the nutrients …

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Simulation Of The 1979 Spring Bloom In The Mid-Atlantic Bight: A Coupled Physical/Biological/Optical Model, Watson W. Gregg, John J. Walsh Apr 1992

Simulation Of The 1979 Spring Bloom In The Mid-Atlantic Bight: A Coupled Physical/Biological/Optical Model, Watson W. Gregg, John J. Walsh

Marine Science Faculty Publications

A coupled physical/biological/optical model was developed to investigate the causes of phytoplankton variability in the spring 1979 Mid-Atlantic Bight (MAB) as observed in Coastal Zone Color Scanner (CZCS) imagery, and to estimate the magnitude and variability of primary production. The model incorporated advection, mixing, sinking, growth as a function of light, temperature, and nutrient availability, and death as a function of ingestion. These variables were assumed to determine the large-scale, low-frequency variability of phytoplankton distributions the model also contained two phytoplankton groups, netplankton and nanoplankton, which differed in maximum growth rate, sinking rate, and specific light absorption. The model produced …

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Concentration Of Microbial Populations From Aquatic Environments By Vortex Flow Filtration, Sunny C. Jiang, Jennifer M. Thurmond, Scott L. Pichard, John H. Paul Feb 1992

Concentration Of Microbial Populations From Aquatic Environments By Vortex Flow Filtration, Sunny C. Jiang, Jennifer M. Thurmond, Scott L. Pichard, John H. Paul

Marine Science Faculty Publications

Vortex Flow Filtration was used to concentrate particulate DNA, chlorophyll a and bacteria from freshwater, estuarine, coastal and oligotrophic marine environments. A Membrex Benchmark System with either a 100 kD or a 0.45-mu-m filter and a large-scale Pacesetter System with a 100 kD filter were used. The Benchmark System is ideal for processing 100 ml to 50 l of water, while the Pacesetter is designed for working with volumes from 20 l up to hundreds of liters. The Benchmark System with a 100 kD filter yielded an average recovery of 81.7, 83.3 and 80.5% respectively for particulate DNA, chlorophyll a …

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The Phytoplankton Bloom In The Northwestern Arabian Sea During The Southwest Monsoon Of 1979, John C. Brock, Charles R. Mcclain, Mark E. Luther, William W. Hay Nov 1991

The Phytoplankton Bloom In The Northwestern Arabian Sea During The Southwest Monsoon Of 1979, John C. Brock, Charles R. Mcclain, Mark E. Luther, William W. Hay

Marine Science Faculty Publications

The biological variability of the northwestern Arabian Sea during the 1979 southwest monsoon has been investigated by the synthesis of satellite ocean color remote sensing with analysis of in situ hydrographic and meteorological data sets and the results of wind-driven modeling of upper ocean circulation. The phytoplankton bloom in the northwestern Arabian Sea peaked during August-September, extended from the Oman coast to about 65-degrees-E, and lagged the development of open-sea upwelling by at least 1 month. In total, the pigment distributions, hydrographic data, and model results all suggest that the bloom was driven by spatially distinct upward nutrient fluxes to …

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Reflectance Model For Quantifying Chlorophyll-A In The Presence Of Productivity Degradation Products, Kendall L. Carder, S. K. Hawes, K. A. Baker, R. C. Smith, R. G. Steward, B. G. Mitchell Nov 1991

Reflectance Model For Quantifying Chlorophyll-A In The Presence Of Productivity Degradation Products, Kendall L. Carder, S. K. Hawes, K. A. Baker, R. C. Smith, R. G. Steward, B. G. Mitchell

Marine Science Faculty Publications

Marine colored dissolved organic matter (CDOM) (also gilvin or yellow substance) absorbs light at an exponentially decreasing rate as a function of wavelength. From 410 nm to about 640 nm, particulate phytoplankton degradation products including pheopigments, detritus, and bacteria have absorption curves that are similar in shape to that of CDOM. In coastal areas and areas downstream from upwelling regions, these constituents of seawater often absorb much more light than do living phytoplankton, leading to errors in satellite-derived chlorophyll estimates as high as 133%. Proposed NASA sensors for the 1990s will have spectral channels as low as 412 nm, permitting …

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15N/14N And 13C/12C In Weddell Sea Invertebrates: Implications For Feeding Diversity, Greg H. Rau, Thomas L. Hopkins, Joseph J. Torres Oct 1991

15N/14N And 13C/12C In Weddell Sea Invertebrates: Implications For Feeding Diversity, Greg H. Rau, Thomas L. Hopkins, Joseph J. Torres

Marine Science Faculty Publications

Biomass delta-C-13, delta-N-15, and C/N were measured for each of 29 taxa of pelagic invertebrates sampled from the Weddell Sea in March 1986. The delta-C-13 values of these animals ranged from -33.2 to -23.9 parts per thousand, and a significant negative logarithmic relationship was observed between these values and biomass C/N. This implies that the relative proportion of carbon-rich C-13-depleted lipid in these animals significantly influenced the delta-C-13 of their bulk biomass. No such relationship with C/N is evident with respect to biomass delta-N-15 where values ranged from -1.2 to +7.3 parts per thousand. This spread of values reflects a …

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On The Seasonal Phytoplankton Concentration And Sea Surface Temperature Cycles Of The Gulf Of Mexico As Determined By Satellites, Frank E. Muller-Karger, John J. Walsh, Robert H. Evans, Mark B. Meyers Jul 1991

On The Seasonal Phytoplankton Concentration And Sea Surface Temperature Cycles Of The Gulf Of Mexico As Determined By Satellites, Frank E. Muller-Karger, John J. Walsh, Robert H. Evans, Mark B. Meyers

Marine Science Faculty Publications

Monthly climatologies of near‐surface phytoplankton pigment concentration and sea surface temperature (SST) were derived for the Gulf of Mexico from multiyear series of coastal zone color scanner (CZCS) (November 1978 to November 1985) and advanced very high resolution radiometer (AVHRR) (January 1983 to December 1987) images. We complement these series with SST from the comprehensive ocean‐atmosphere data set (1946–1987) and Climate Analysis Center (1982–1990), and hydrographic profile data from the NOAA National Oceanographic Data Center (1914–1985). The CZCS ocean color satellite data provide the first climatological time series of phytoplankton concentration for the region. The CZCS images show that seasonal …

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On The Annual Cycle Of Equatorial Upwelling In The Central Atlantic-Ocean, Thomas J. Weingartner, Robert H. Weisberg Jan 1991

On The Annual Cycle Of Equatorial Upwelling In The Central Atlantic-Ocean, Thomas J. Weingartner, Robert H. Weisberg

Marine Science Faculty Publications

The annual cycle of the upper ocean's vertical velocity component (w) on the equator at 28°W is examined by integrating the continuity equation using current meter data from the Seasonal Response of the Equatorial Atlantic Experiment. The annual cycle consists in part of an intense, but brief (∼1 month), upwelling season beginning with the onset of strong easterly wind stress in boreal spring. This upwelling is followed by weaker downwelling during the summer despite the persistence of strong easterly wind stress. The record-length averaged w profile shows that maximum upwelling (0.6 x 10-3cm s-1) …

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The Seasonal Circulation Of The Upper Ocean In The Bay Of Bengal, James T. Potemra, Mark E. Luther Jan 1991

The Seasonal Circulation Of The Upper Ocean In The Bay Of Bengal, James T. Potemra, Mark E. Luther

Marine Science Faculty Publications

Analysis of the results of a multilayer, adiabatic, numerical model of the upper Indian Ocean, driven by climatological monthly mean winds, shows that the simulated currents in the northeastern Indian Ocean are in general agreement with available observations and interpretations. The main features of the ocean currents include large anticyclonic flow in the Bay of Bengal surface waters during the northern hemisphere winter. This gyre decays into eddies in spring and then transitions into a weaker, cyclonic gyre by late summer. The western recirculation region of this flow is an intensified western boundary current which changes direction twice during the …

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A Description Of The Annual Cycle In Sea Surface Temperature And Upper Ocean Heat In The Equatorial Atlantic, Thomas J. Weingartner, Robert H. Weisberg Jan 1991

A Description Of The Annual Cycle In Sea Surface Temperature And Upper Ocean Heat In The Equatorial Atlantic, Thomas J. Weingartner, Robert H. Weisberg

Marine Science Faculty Publications

Temperature and velocity time series, obtained by surface moorings during the Seasonal Response of the Equatorial Atlantic Experiment, are used to investigate the role of ocean dynamics upon the annual cycle of equatorial sea surface temperature (SST) and upper ocean heat. The annual cycle in SST is explained by different mechanisms, each operant at different phases of the cycle. The boreal springtime decrease in SST results from upwelling in response to the seasonal intensification of easterly wind stress. This upwelling causes the seasonal formation of the cold tongue along the equator in the central and eastern portions of the basin. …

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Tectonic Evolution Of The Easter Microplate, David F. Naar, R. N. Hey Jan 1991

Tectonic Evolution Of The Easter Microplate, David F. Naar, R. N. Hey

Marine Science Faculty Publications

The plate tectonic history of the Easter microplate has been reconstructed by “closing” the microplate in a series of steps using the Pacific-Nazca magnetic anomalies north and south of the microplate and the NUVEL 1 global plate motion model. After each step, the Easter microplate was rotated rigidly to match the Nazca and Pacific anomalies. Gaps and overlaps formed by this kinematic treatment indicate compressional and tensional deformation, respectively, and show that rigid plate motions are insufficient to explain the complete tectonic evolution. Analysis of the magnetic anomaly data was guided by contoured SeaMARC II, Sea Beam, and 3.5-kHz bathymetry …

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A Linear Analysis Of Equatorial Atlantic Ocean Thermocline Variability, Robert H. Weisberg, T. Y. Tang Dec 1990

A Linear Analysis Of Equatorial Atlantic Ocean Thermocline Variability, Robert H. Weisberg, T. Y. Tang

Marine Science Faculty Publications

Observed variations in the Atlantic Ocean's equatorial thermocline are compared at four locations with simultations using an analytical reduced-gravity model. The comparison shows the essential features of the seasonal wind-forced thermocline response to be accounted for by a linear superposition of equatorial long waves, evolving basinwide, tending to bring the zonal pressure gradient into balance with the wind stress. A frequency response function is derived whose properties provide a basis for discussing the large scale features of the equatorial Atlantic Ocean's seasonal cycle-for example, its evolution along the equator, the maximum upwelling region observed in the Gulf of Guinea and …

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Variability In Upwelling Fields In The Northwestern Indian Ocean 2. Data‐Model Comparison At 9000 Years B.P., Warren L. Prell, Rebecca E. Marvil, Mark E. Luther Jan 1990

Variability In Upwelling Fields In The Northwestern Indian Ocean 2. Data‐Model Comparison At 9000 Years B.P., Warren L. Prell, Rebecca E. Marvil, Mark E. Luther

Marine Science Faculty Publications

Theoretical investigations, in the form of general circulation model (GCM) simulations and empirical studies of pollen, lake levels, and marine sediments suggest that the Indian summer monsoon was intensified 9000 years ago, at a time of increased summer radiation (about 8%) in the northern hemisphere. The southwesterly summer monsoon winds and their pattern of wind stress curl cause coastal upwelling along the coast of Arabia. Stronger summer winds, therefore, should intensify coastal upwelling. Incorporation of the broad‐scale GCM winds into a high‐resolution ocean model of the Arabian Sea produces distinct patterns of stronger upwelling at 9000 years B.P. To verify …

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Variability In Upwelling Fields In The Northwestern Indian Ocean 1. Model Experiments For The Past 18,000 Years, Mark E. Luther Jan 1990

Variability In Upwelling Fields In The Northwestern Indian Ocean 1. Model Experiments For The Past 18,000 Years, Mark E. Luther

Marine Science Faculty Publications

A nonlinear reduced gravity ocean model is used to assess the effects of changes in the monsoon winds during glacial and interglacial conditions on the seasonal circulation in the northwestern Indian Ocean. Winds from the National Center for Atmospheric Research Community Climate Model simulations for 18 kyr B.P. (the most recent glacial maximum and a period of weaker monsoon winds), 9 kyr B.P. (near the beginning of the present interglacial and a period of stronger monsoon winds), and present‐day (0 kyr B.P.) conditions are used to drive the model to a steady seasonal cycle. Strength of upwelling fields are inferred …

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Interannual Differences Of Geosat Altimeter Heights And Sea Level: The Importance Of A Datum, Klaus Wyrtki, Gary Mitchum Jan 1990

Interannual Differences Of Geosat Altimeter Heights And Sea Level: The Importance Of A Datum, Klaus Wyrtki, Gary Mitchum

Marine Science Faculty Publications

Sea surface height data from the Geosat altimeter are compared with island sea level data from 18 gauges in the western and central tropical Pacific during December 1986 to November 1987. Care was taken to ensure that the two data sets are referenced to the same mean surface. This was done by requiring that both data sets have a zero mean sea level over the period April 1985 to April 1986. When the annual means are computed at each station in the later time period, we find that the annual mean sea surface height values have drifted away from the …

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Effect Of Rotation On Vertical Mixing And Associated Turbulence In Stratified Fluids, L. H. Kantha, A. Rosati, B. Galperin Jan 1989

Effect Of Rotation On Vertical Mixing And Associated Turbulence In Stratified Fluids, L. H. Kantha, A. Rosati, B. Galperin

Marine Science Faculty Publications

Combined effects of stratification and rotation on vertical mixing and the characteristics of associated small-scale turbulence are explored using second-moment closure methodology; the rotational terms in the equations for Reynolds stresses and turbulent heat fluxes are retained, not ignored as in earlier works. Semianalytical results valid for arbitrary values of rotation and stratification are derived by further invoking the local equilibrium limit of closure. Two cases are considered: nonzero vertical rotation and nonzero meridional rotation; the latter case is of more general interest in geophysics because of its potential application to equatorial mixed layers. In both cases the influence of …

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Three-Dimensional Inversion Of The Magnetic Field Over The Easter-Nazca Propagating Rift Near 25°S, 112°25′W, Jean-Christophe Sempere, Jeff Gee, David F. Naar, Richard N. Hey Jan 1989

Three-Dimensional Inversion Of The Magnetic Field Over The Easter-Nazca Propagating Rift Near 25°S, 112°25′W, Jean-Christophe Sempere, Jeff Gee, David F. Naar, Richard N. Hey

Marine Science Faculty Publications

The Easter microplate boundary configuration is being reorganized by rift propagation. A Sea Beam survey of the Easter-Nazca spreading center, which forms the eastern boundary of the microplate, has revealed the presence of a young propagating rift growing northward (Naar and Hey, 1986). The tip of the propagating rift is associated with a high-amplitude positive magnetic anomaly. We have performed a three-dimensional inversion of the magnetic field over the propagating rift tip area. The magnetization solution suggests that the western and eastern pseudofaults strike 014° and 338°, respectively, and converge near the rift tip. These orientations yield a propagation to …

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The Wind‐Driven Seasonal Circulation In The Southern Tropical Indian Ocean, Karen E. Woodberry, Mark E. Luther, James J. O'Brien Jan 1989

The Wind‐Driven Seasonal Circulation In The Southern Tropical Indian Ocean, Karen E. Woodberry, Mark E. Luther, James J. O'Brien

Marine Science Faculty Publications

A numerical model of the Indian Ocean, driven by climatological monthly mean winds, realistically simulates the major features of the large scale upper ocean circulation observed in the southern hemisphere and equatorial regions. The principal feature in the tropical Indian Ocean is a basin‐wide clockwise southern hemisphere (cyclonic) gyre comprised of the South Equatorial Current to the south, the South Equatorial Countercurrent to the north, and the East African Coastal Current in the west. Rossby waves propagate westward in the shear zone between the South Equatorial Current and the South Equatorial Countercurrent, and are obstructed and partially reflected by the …

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Aspects Of The Ecology Of The Mesopelagic Fish Gonostoma Elongatum (Gonostomatidae, Stomiiformes) In The Eastern Gulf Of Mexico, Thomas M. Lancraft, Thomas L. Hopkins, Joseph J. Torres Nov 1988

Aspects Of The Ecology Of The Mesopelagic Fish Gonostoma Elongatum (Gonostomatidae, Stomiiformes) In The Eastern Gulf Of Mexico, Thomas M. Lancraft, Thomas L. Hopkins, Joseph J. Torres

Marine Science Faculty Publications

Gonostoma elongatum is an important mesopelagic fish found throughout the world at subtropical-tropical latitudes. This study examined its distribution, abundance and life history in the eastern Gulf of Mexico. The species was a strong diel migrator, found from 25 to 325 m at night and from 425 to 725 m during the day with small fish occurring shallower than large fish. Numerical abundance and biomass were high, rivaling the dominant species of myctophids in the Gulf of Mexico. There no obvious seasonal fluctuations in population abundance. G. elongatum is a protandric hermaphrodite whose population breeds throughout the year and females …

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Instability Waves In The Equatorial Atlantic Ocean, Robert H. Weisberg, T. J. Weingartner Nov 1988

Instability Waves In The Equatorial Atlantic Ocean, Robert H. Weisberg, T. J. Weingartner

Marine Science Faculty Publications

Evidence is presented for the generation of planetary waves by barotropic instability within the cyclonic shear region of the Atlantic Ocean's South Equatorial Current (SEC). Immediately following the springtime intensification of the southeast trade wind, which accelerates the SEC westward, a packet of waves with central periodicity of around 25 days is observed lasting for about three cycles. Independent wavenumber analyses on 1983 and 1984 data give newly identical zonal wavelengths and phase speed estimates of around 1100 km and −50 cm s−1. The waves are anisotropic and spatially inhomogeneous with generation confined primarily to the mixed layer. …

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Vertical Structure Of Low-Frequency Variability In The Eastern Equatorial Pacific Ocean, T. Y. Tang, Robert H. Weisberg, D. Halpern Jul 1988

Vertical Structure Of Low-Frequency Variability In The Eastern Equatorial Pacific Ocean, T. Y. Tang, Robert H. Weisberg, D. Halpern

Marine Science Faculty Publications

The vertical structure of low frequency velocity and temperature variability in the eastern equatorial Pacific Ocean is examined using surface and subsurface moored current meter data from 0°, 110°W between 20 and 3027 m depths over the period 30 March 1980 to 2 February 1981. Three methods of analysis are employed: vertical coherence, empirical orthogonal functions, and linear least-squares dynamical mode decompositions. Direct evidence is given for the existence of first baroclinic mode Kelvin waves in the east component of velocity and vertical displacement (estimated from temperature) in that the vertical displacement is coherent and in phase over the water …

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The Mathematician Paleoplate, J. Mammerickx, D. F. Naar, R. L. Tyce Jan 1988

The Mathematician Paleoplate, J. Mammerickx, D. F. Naar, R. L. Tyce

Marine Science Faculty Publications

The Pacific seafloor is littered with small fragments of lithosphere captured from adjacent plates by past plate boundary reorganizations. One of the clearest examples of such a reorganization is documented in the Mathematician Seamounts region, where a distinctive geomorphology and well-developed magnetic anomalies are present. This reorganization involved a short-lived microplate between the failing Mathematician Ridge and a new propagating spreading center: the East Pacific Rise. It produced a transfer of a fragment of lithosphere from the Farallon to the Pacific plate, and also created a number of landforms and magnetic patterns, within and on the margins of the captured …

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Verification Of A Numerical Ocean Model Of The Arabian Sea, Ray C. Simmons, Mark E. Luther, James J. O'Brien, David M. Legler Jan 1988

Verification Of A Numerical Ocean Model Of The Arabian Sea, Ray C. Simmons, Mark E. Luther, James J. O'Brien, David M. Legler

Marine Science Faculty Publications

A case study evaluating the predictive capability of an upper layer circulation model of the northwest Indian Ocean is presented. The model is a nonlinear, reduced gravity model incorporating realistic boundary geometry and is forced by observed winds. Model results for the fall of 1985 are compared with and evaluated against U.S. Navy bathythermograph and NOAA satellite data collected during August–November 1985. An assessment is made of the model's ability to simulate correctly the circulation structure. Ship wind observations are converted to wind stress for model forcing by a procedure developed by Legler and Navon (1988). The model is only …

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Abundance And Distribution Of Herbaceous Angiosperms In Grass-Sedge Marshes Of West-Central Florida: The Effect Of Seasonal Water-Level Fluctuation, Pamela S. Botts Jul 1987

Abundance And Distribution Of Herbaceous Angiosperms In Grass-Sedge Marshes Of West-Central Florida: The Effect Of Seasonal Water-Level Fluctuation, Pamela S. Botts

USF Tampa Graduate Theses and Dissertations

Grass-sedge marshes in west-central Florida were studied to determine the abundances and distributions of herbaceous angiosperms. Cluster analysis, reciprocal averaging, and a biotic boundaries technique were used to analyze the relationship between community composition and depth within the marsh. Shallow areas were dominated by Rhynchospora filifolia, Dichanthelium sabulorum, and Rhynchospora cephalantha. Abundances of the species fluctuated seasonally and varied between marshes. Deep areas of individual marshes differed markedly from shallow areas and from each other. A deep, well-drained marsh supported a monospecific stand of Juncus repens, while a less deep, but poorly drained marsh had a …

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Distribution And Molecular Weight Of Dissolved Dna In Subtropical Estuarine And Oceanic Environments, Mary F. Deflaun, John H. Paul, Wade H. Jeffrey May 1987

Distribution And Molecular Weight Of Dissolved Dna In Subtropical Estuarine And Oceanic Environments, Mary F. Deflaun, John H. Paul, Wade H. Jeffrey

Marine Science Faculty Publications

Dissolved DNA and a series of microbial biomass and activity parameters were measured in offshore, coastal, estuarine and coral reef environments of the southeast Gulf of Mexico. Oceanic concentrations of dissolved DNA ranged from 0.2 to 19 μg 1-1 and decreased as a function of distance from shore and depth in the water column. Dissolved DNA concentrations were greater than half the particulate DNA content in offshore environments (̄x̄ = 63 ± 45 %) but were a smaller percentage of particulate DNA in nearshore and estuarine environments (̄x̄ = 35 ± 21 %). Dissolved DNA correlated better with bacterial …

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Velocity And Temperature Observations During The Seasonal Response Of The Equatorial Atlantic Experiment At 0 Degrees, 28 Degrees W, Robert H. Weisberg, J. H. Hickman, T. Y. Tang, T. J. Weingartner May 1987

Velocity And Temperature Observations During The Seasonal Response Of The Equatorial Atlantic Experiment At 0 Degrees, 28 Degrees W, Robert H. Weisberg, J. H. Hickman, T. Y. Tang, T. J. Weingartner

Marine Science Faculty Publications

Continuous 2.7‐year time series of upper ocean currents and temperature at 0°, 28°W collected during the Seasonal Response of the Equatorial Atlantic Experiment are presented. The thermocline underwent distinctive annual cycles in response to forcing by the surface wind stress, and the core of the Equatorial Undercurrent tracked the thermocline. While the vertical position of the thermocline and the undercurrent appear to be simply related, the transport of the undercurrent did not show a replicating annual cycle, and the speed at the undercurrent core remained relatively constant. Near surface flow when averaged over the 2.7 years was not statistically different …

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M2 Tidal Currents In The Eastern Equatorial Pacific Ocean, Robert H. Weisberg, D. Halpern, T. Y. Tang, S. M. Hwang Apr 1987

M2 Tidal Currents In The Eastern Equatorial Pacific Ocean, Robert H. Weisberg, D. Halpern, T. Y. Tang, S. M. Hwang

Marine Science Faculty Publications

Current meter measurements recorded over the water column at 10 depths ranging from 20 m to 3027 m using surface and subsurface moorings near 0°, 110°W are analyzed for the M2 tidal current over a 10‐month sampling interval. A kinematical description is given by month and depth, followed by a decomposition into a barotropic mode and three baroclinic modes. The barotropic tide was dominant, and its hodograph was stable over the 10 months sampled. The baroclinic tide was random, isotropic, and without mode preference.

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Further Studies On The Response Of The Equatorial Thermocline In The Atlantic Ocean To The Seasonally Varying Trade Winds, Robert H. Weisberg, T. Y. Tang Apr 1987

Further Studies On The Response Of The Equatorial Thermocline In The Atlantic Ocean To The Seasonally Varying Trade Winds, Robert H. Weisberg, T. Y. Tang

Marine Science Faculty Publications

Upper ocean temperature data obtained during the Seasonal Response of the Equatorial Atlantic experiment and the Francais Ocean et Climat dans l'Atlantique Equatorial program are used to describe the variations of the thermocline observed along the equator from February 1983 to September 1984. In response to rapid seasonal changes in zonal wind stress, the thermocline underwent sequences of upwelling followed by downwelling or conversely, depending upon whether the winds were intensifying or relaxing. These sequences increased systematically in magnitude and duration to the east. Both the sequential behavior and its zonal inhomogeneity represent departures from the slowly varying and in-phase …

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