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Accuracy Assessment Of The Large-Scale Dynamic Ocean Topography From Topex/Poseidon Altimetry, B. D. Tapley, D. P. Chambers, C. K. Shum, R. J. Eanes, J. C. Ries, R. H. Stewart
Accuracy Assessment Of The Large-Scale Dynamic Ocean Topography From Topex/Poseidon Altimetry, B. D. Tapley, D. P. Chambers, C. K. Shum, R. J. Eanes, J. C. Ries, R. H. Stewart
Marine Science Faculty Publications
The quality of TOPEX/POSEIDON determinations of the global scale dynamic ocean topography have been assessed by determining mean topography solutions for successive 10-day repeat cycles and by examining the temporal changes in the sea surface topography to identify known features. The assessment is based on the analysis of TOPEX altimeter data for cycles 1 through 36. Important errors in the tide model used to correct the altimeter data have been identified. The errors were reduced significantly by use of a new tide model derived with the TOPEX/POSEIDON measurements. Maps of the global 1-year mean topography, produced using four of the …
Metabolism Of Antarctic Micronektonic Crustacea As A Function Of Depth Of Occurrence And Season, Joseph J. Torres, A. V. Aarset, J. Donnelly, Thomas L. Hopkins, T. M. Lancraft, D. G. Ainley
Metabolism Of Antarctic Micronektonic Crustacea As A Function Of Depth Of Occurrence And Season, Joseph J. Torres, A. V. Aarset, J. Donnelly, Thomas L. Hopkins, T. M. Lancraft, D. G. Ainley
Marine Science Faculty Publications
Oxygen comsumption rates were determined on 21 species of crustaceans typical of the Southern Ocean micronektonic crustacean assemblage during spring (November), fall (March), and winter (June-August). Specimens were collected in the Scotia-Weddell Sea region in the vicinity of 60-degrees-S, 40-degrees-W in the upper 1000 m of the water column. Respiration (y, mul O2mg-1 wet mass h-1) declined with depth of occurrence (x, m) according to the equation y = 0.125 x-0.172 +/- 0.052 (p < 0.05) despite the isothermal character of the water column, suggesting that lower metabolic rates are a temperature-independent adaptation to life in the deep sea. Three species of Crustacea showed a lowered metabolism during the winter season: the krill Euphausia superba and the 2 hyperiid amphipods Cyllopus lucasii and Vibilia stebbingi. Critical oxygen partial pressure (Pc) varied between 29 and 52 mm Hg, well below the lowest PO2 found in the water column. It is suggested that the long nights of the Antarctic winter decrease the effectiveness of visual predation in the epipelagic zone, allowing lowered metabolic rates to be a viable overwintering strategy for some species.
Effect Of Decompression On Mesopelagic Gelatinous Zooplankton: A Comparison Of In-Situ And Shipboard Measurements Of Metabolism, T. G. Bailey, Joseph J. Torres, M. J. Youngbluth, G. P. Owen
Effect Of Decompression On Mesopelagic Gelatinous Zooplankton: A Comparison Of In-Situ And Shipboard Measurements Of Metabolism, T. G. Bailey, Joseph J. Torres, M. J. Youngbluth, G. P. Owen
Marine Science Faculty Publications
Weight- and carbon-specific rates of respiration for 4 mesopelagic gelatinous zooplankton (2 ctenophores, 1 trachymedusa and 1 pelagic holothurian) measured in situ were 2 to 5 times higher than those from shipboard incubations. These results support the theory that removal of deep-living gelatinous species from natural environments can adversely affect their metabolism. The disparity between in situ and shipboard treatments is most simply explained by an interaction between pressure and activity, i.e. a loss of motor activity due to decompression occurred among animals used in shipboard experiments.
Proximate Composition And Overwintering Strategies Of Antarctic Micronektonic Crustacea, Joseph J. Torres, J. Donnelly, Thomas L. Hopkins, T. M. Lancraft, A. V. Aarset, D. G. Ainley
Proximate Composition And Overwintering Strategies Of Antarctic Micronektonic Crustacea, Joseph J. Torres, J. Donnelly, Thomas L. Hopkins, T. M. Lancraft, A. V. Aarset, D. G. Ainley
Marine Science Faculty Publications
Proximate (protein, lipid, carbohydrate and chitin) and elemental (carbon and nitrogen) composition were determined for 18 species of Antarctic micronektonic Crustacea, representing the majority of species found in the Antarctic water column. Individuals used in the analyses were captured during fall and winter; for 8 species data were collected in both seasons. Seven of the 8 species showed some evidence that combustion of body stores were an aid to surviving the winter months; comparison with data from other investigators suggests that most of the species inhabiting shallow and mid-depths exhibit some degree of combustion of body stores during winter. Three …
Equatorially Trapped Waves Of A Coupled Ocean-Atmosphere System, Chunzai Wang, Robert H. Weisberg
Equatorially Trapped Waves Of A Coupled Ocean-Atmosphere System, Chunzai Wang, Robert H. Weisberg
Marine Science Faculty Publications
Equatorially trapped waves of a simplified coupled ocean-atmosphere system are described by applying the formalism for conventional equatorially trapped waves with the assumption that the zonal wind stress and sea surface temperature perturbations are proportional. In this system, inertial-gravity and Rossby-gravity waves are unaffected by coupling whereas Rossby and Kelvin waves are affected, and in the low-frequency limit, these Rossby and Kelvin waves transform to slow westward and eastward propagating wave modes, respectively. The primary modifications by air-sea coupling are a decrease in phase speed and an increase in meridional scale. The properties of these coupled waves are useful in …
Structure And Trophic Ecology Of A Low Latitude Midwater Decapod And Mysid Assemblage, Thomas L. Hopkins, Mark E. Flock, John V. Gartner Jr, Joseph J. Torres
Structure And Trophic Ecology Of A Low Latitude Midwater Decapod And Mysid Assemblage, Thomas L. Hopkins, Mark E. Flock, John V. Gartner Jr, Joseph J. Torres
Marine Science Faculty Publications
The micronektonic crustacean assemblage in the eastern Gulf of Mexico is an extension of the low latitude Atlantic and Caribbean faunas. Species showed highly varying diel distribution patterns ranging from a strong vertical migration to the epipelagic zone to absence of any migration resulting in a permanent residence deep in the mesopelagic zone. As in other low latitude areas, decapod species with variegated pigment patterns centered above 650 m during the day, whereas 'all-red' species centered below this depth. Standing stocks were estimated at 0.18 g dry wt m-2 and 3 ind. m-2 in the upper 1000 m. Diet analysis …
Interpretation Of The Coastal Zone Color Scanner Signature Of The Orinoco River Plume, Herschel T. Hochman, Frank E. Muller-Karger, John J. Walsh
Interpretation Of The Coastal Zone Color Scanner Signature Of The Orinoco River Plume, Herschel T. Hochman, Frank E. Muller-Karger, John J. Walsh
Marine Science Faculty Publications
The Caribbean Sea is an area that traditionally has been considered oligotrophic, even though the Orinoco River contributes large quantities of fresh water, nutrients, and other dissolved materials to this region during the wet boreal (fall) season. Little is known about the impact of this seasonal river plume, which extends from Venezuela to Puerto Rico shortly after maximum discharge. Here we present results from a study of the bio-optical characteristics of the Orinoco River plume during the rainy season. The objective was to determine whether the coastal zone color scanner (CZCS) and the follow-on sea-viewing wide-field-of-view sensor (SeaWiFS) satellite instrument …
A Numerical Analysis Of Shipboard And Coastal Zone Color Scanner Time Series Of New Production Within Gulf Stream Cyclonic Eddies In The South Atlantic Bight, J. Raymond Pribble, John J. Walsh, Dwight A. Dieterle, Frank E. Muller-Karger
A Numerical Analysis Of Shipboard And Coastal Zone Color Scanner Time Series Of New Production Within Gulf Stream Cyclonic Eddies In The South Atlantic Bight, J. Raymond Pribble, John J. Walsh, Dwight A. Dieterle, Frank E. Muller-Karger
Marine Science Faculty Publications
Eddy-induced upwelling occurs along the western edge of the Gulf Stream between Cape Canaveral, Florida, and Cape Hatteras, North Carolina, in the South Atlantic Bight (SAB). Coastal zone color scanner images of 1-km resolution spanning the period April 13-21, 1979, were processed to examine these eddy features in relation to concurrent shipboard and current/temperature measurements at moored arrays. A quasi-one-dimensional (z), time-dependent biological model, using only nitrate as a nutrient source, has been combined with a three-dimensional physical model in an attempt to replicate the observed phytoplankton field at the northward edge of an eddy. The model is applicable only …
The Effects Of Temporal Variability Of Mixed Layer Depth On Primary Productivity Around Bermuda, W. Paul Bissett, Mark B. Meyers, John J. Walsh, Frank E. Muller-Karger
The Effects Of Temporal Variability Of Mixed Layer Depth On Primary Productivity Around Bermuda, W. Paul Bissett, Mark B. Meyers, John J. Walsh, Frank E. Muller-Karger
Marine Science Faculty Publications
Temporal variations in primary production and surface chlorophyll concentrations, as measured by ship and satellite around Bermuda, were simulated with a numerical model. In the upper 450 m of the water column, population dynamics of a size‐fractionated phytoplankton community were forced by daily changes of wind, light, grazing stress, and nutrient availability. The temporal variations of production and chlorophyll were driven by changes in nutrient introduction to the euphotic zone due to both high‐ and low‐frequency changes of the mixed layer depth within 32°‐34°N, 62°‐64°W between 1979 and 1984. Results from the model derived from high‐frequency (case 1) changes in …
Seasonal And Diel Abundance Of Viruses And Occurrence Of Lysogeny/Bacteriocinogeny In The Marine Environment, Sunny C. Jiang, John H Paul
Seasonal And Diel Abundance Of Viruses And Occurrence Of Lysogeny/Bacteriocinogeny In The Marine Environment, Sunny C. Jiang, John H Paul
Marine Science Faculty Publications
To understand the role of viruses in the marine environment, it is important to know the factors affecting their temporal distribution and the abundance of lysogens. We therefore performed a seasonal and a diel study on viral distribution in Tampa Bay, Florida, USA, and detected the abundance of lysogens and bacteriocinogens amongst marine bacterial isolates from diverse marine environments. We investigated the distribution of viruses, bacterial direct counts, chlorophyll a (chl a), salinity and temperature during a 13 mo period in the Tampa Bay estuary. The results indicated that the viral population had a strong seasonal pattern with the highest …
Comparison Of Topex Sea Surface Heights And Tide Gauge Sea Levels, Gary T. Mitchum
Comparison Of Topex Sea Surface Heights And Tide Gauge Sea Levels, Gary T. Mitchum
Marine Science Faculty Publications
TOPEX sea surface height data from the first 300 days of the mission are compared to sea level data from 71 tide gauges. The initial comparison uses sea surface height data processed according to standard procedures as defined in the users handbook. It is found that the median correlations for island and for coastal tide gauges are 0.53 and 0.42, respectively. The analogous RMS differences between the two data sets are 7.9 and 10.4 cm. The comparisons improve significantly when a 60-day harmonic is fit to the differences and removed. This period captures aliased M2 and S2 tidal energy that …
Modeling Rotating Flows With Neutral And Unstable Stratification, Samuel Hassid, Boris Galperin
Modeling Rotating Flows With Neutral And Unstable Stratification, Samuel Hassid, Boris Galperin
Marine Science Faculty Publications
We investigate the effect of rotation on the structure of turbulence in neutral and convective mixed layers and assess the applicability of the Reynolds stress turbulence closure models to studies of deep convection. Unlike in the case of stable stratification, where rotational contribution is limited (Galperin et al., 1989), in neutral and convective flows this contribution is significant. The rotational terms endow eddy viscosity and eddy diffusivity with tensorial properties and algebraic complexity. In the present study we thoroughly investigate the mathematical features of this tensorial eddy viscosity-eddy diffusivity formulation. To ensure physical readability of the model, we found it …