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Coherence Of Internal Tide Modulations Along The Hawaiian Ridge, Gary T. Mitchum, Stephen M. Chiswell
Coherence Of Internal Tide Modulations Along The Hawaiian Ridge, Gary T. Mitchum, Stephen M. Chiswell
Marine Science Faculty Publications
Long time series of sea level from tide gauges along the north side of the Hawaiian Ridge and shorter series of dynamic heights inferred from inverted echo sounders moored just north of the main Hawaiian Islands are examined for evidence of internal tides at the M2 frequency. We find that the amplitudes and phases of the M2 tidal components have low-frequency variability, which is consistent with a superposition of an internal tide with the larger barotropic tide. Further, the low-frequency variability is correlated with low-frequency changes in the depth of the pycnocline, which suggests a simple physical mechanism …
Meeting Explores Sensor Technology For Remote, Interactive Aquatic Experiments, Kendra L. Daly
Meeting Explores Sensor Technology For Remote, Interactive Aquatic Experiments, Kendra L. Daly
Marine Science Faculty Publications
Oceans, lakes, rivers, and groundwater are complex, dynamic environments in which physical, chemical, and biological processes occur over varying temporal and spatial scales (e.g., eddies, nutrient fluxes, patchiness of organisms, benthic processes, and pollution). In addition, deep, remote, or hostile systems such as hydrothermal vents and polar regions traditionally are poorly sampled, but are important to understanding global biogeochemical and hydrological cycles. In the coming decades, moored, cabled, and autonomous observatories will be used to investigate a spectrum of basic processes in aquatic environments. In anticipation of the need to develop or re‐engineer sensors to measure physical, chemical, biological, and …
Orbitally Induced Climate And Geochemical Variability Across The Oligocene/Miocene Boundary, Hilary A. Paul, James C. Zachos, Benjamin P. Flower, Aradhna Tripati
Orbitally Induced Climate And Geochemical Variability Across The Oligocene/Miocene Boundary, Hilary A. Paul, James C. Zachos, Benjamin P. Flower, Aradhna Tripati
Marine Science Faculty Publications
To assess the influence of orbital-scale variations on late Oligocene to early Miocene climate and ocean chemistry, high-resolution (similar to 5 kyr) benthic foraminiferal carbon and oxygen isotope and percent coarse fraction time series were constructed for Ocean Drilling Program site 929 on Ceara Rise in the western equatorial Atlantic. These time series exhibit pervasive low- to high-frequency variability across a 5-Myr interval (20.5-25.4 Ma). The records also reveal several large-scale secular variations including two positive (similar to 1.6 parts per thousand) oxygen isotope excursions at 22.95 and 21.1 Ma, suggestive of large but brief glacial maxima (Mi-l and Mi-la …
North Atlantic Intermediate To Deep Water Circulation And Chemical Stratification During The Past 1 Myr, Benjamin P. Flower, D. W. Oppo, J. F. Mcmanus, K. A. Venz, D. A. Hodell, J. L. Cullen
North Atlantic Intermediate To Deep Water Circulation And Chemical Stratification During The Past 1 Myr, Benjamin P. Flower, D. W. Oppo, J. F. Mcmanus, K. A. Venz, D. A. Hodell, J. L. Cullen
Marine Science Faculty Publications
Benthic foraminiferal carbon isotope records from a suite of drill sites in the North Atlantic are used to trace variations in the relative strengths of Lower North Atlantic Deep Water (LNADW), Upper North Atlantic Deep Water (UNADW), and Southern Ocean Water (SOW) over the past 1 Myr. During glacial intervals, significant increases in intermediate-to-deep delta(13)C gradients (commonly reaching >1.2 parts per thousand) are consistent with changes in deep water circulation and associated chemical stratification. Bathymetric delta(13)C gradients covary with benthic foraminiferal delta(18)O and covary inversely with Vostok CO2, in agreement with chemical stratification as a driver of atmospheric CO2 changes. …
Near-Surface Phytoplankton Distribution In The Western Intra-Americas Sea: The Influence Of El Niño And Weather Events, Nelson M. Gonzalez, Frank E. Muller-Karger, Sergio Cerdeira Estrada, Roberto Perez De Los Reyes, Ivan Victora Del Rio, Pedro Cardenas Perez, Ida Mitrani Arenal
Near-Surface Phytoplankton Distribution In The Western Intra-Americas Sea: The Influence Of El Niño And Weather Events, Nelson M. Gonzalez, Frank E. Muller-Karger, Sergio Cerdeira Estrada, Roberto Perez De Los Reyes, Ivan Victora Del Rio, Pedro Cardenas Perez, Ida Mitrani Arenal
Marine Science Faculty Publications
The space-rime variation of phytoplankton pigments in the western Intra-Americas Sea (IAS), in the vicinity of the island of Cuba, is examined using digital images obtained with the Coastal Zone Color Scanner sensor flown aboard the Nimbus 7 satellite from 1978 to 1986. The results are compared to historical in situ hydrographic observations. A marked seasonality in pigment concentration was observed in waters around Cuba, with an average of 0.07 mg m(-3) in summer (April-September) and 0.13 mg m-3 during winter (October-March). The range of variation in pigment concentration was larger in the Gulf of Mexico relative to the western …
The Effects Of Silviculture And Prescribed Burning On Herpetofauna In Florida Sand-Pine Scrub, Stig Ravdal
The Effects Of Silviculture And Prescribed Burning On Herpetofauna In Florida Sand-Pine Scrub, Stig Ravdal
USF Tampa Graduate Theses and Dissertations
Florida sand pine scrub is among the most endangered habitats in the United States and much of the remaining scrub is heavily influenced by management for timber production. In this study the effects of timber management practices on herpetofaunal community diversity and composition were investigated on experimentally manipulated plots near Orlando, Florida. Plots at three sites were either harvested, burned, or treated as a control (unmanipulated). Herpetofauna were trapped using pit-fall drift-fence trapping arrays. Animals were counted, measured, marked and released from March 1996 to June 1998. During this time period 1489 reptiles and amphibians were caught from 31 different …
Form Ia Rbcl Transcripts Associated With A Low Salinity/High Chlorophyll Plume ('Green River') In The Eastern Gulf Of Mexico, John H. Paul, Albin Alfreider, Jordan B. Kang, Roger A. Stokes, Dale Griffin, Lisa Campbell, Erla Ornolfsdottir
Form Ia Rbcl Transcripts Associated With A Low Salinity/High Chlorophyll Plume ('Green River') In The Eastern Gulf Of Mexico, John H. Paul, Albin Alfreider, Jordan B. Kang, Roger A. Stokes, Dale Griffin, Lisa Campbell, Erla Ornolfsdottir
Marine Science Faculty Publications
Coastal plumes of low salinity water that extend hundreds of kilometers offshore into oligotrophic waters are often found in the Gulf of Mexico. To characterize one such feature, a series of photoautotrophic activity and biomass parameters were measured at 2 stations in the eastern Gulf of Mexico, including pigments by high performance liquid chromatography (HPLC), autotrophic picoplankton abundance by flow cytometry, photoautotrophic 14C-HCO3- fixation, and Ribulose-1,5-diphosphate carboxylase large subunit gene (rbcL) transcriptional activity. One sampling site (Stn 4) was in a 15 m deep, low salinity (29.8 ppt) plume 242 km west of Tampa Bay. …
An Upwelling Case Study On Florida's West Coast, Robert H. Weisberg, Bryan D. Black, Zhenjiang Li
An Upwelling Case Study On Florida's West Coast, Robert H. Weisberg, Bryan D. Black, Zhenjiang Li
Marine Science Faculty Publications
Using a combination of satellite sea surface temperature imagery; in situ currents, temperature, and sea level data; and a numerical circulation model, we describe an upwelling event observed along Florida's west coast. Although ubiquitous features of continental shelves, descriptions of coastal upwellings (or downwellings) are generally complicated by the continuum of processes in which they occur. For the case study presented the winds were light, and the baroclinic background currents were steady for several days prior to the event. These conditions allow the evolution of a specific wind-driven upwelling event to be viewed as an initial value problem. The data …
Vhf Radar Detects Oceanic Submesoscale Vortex Along Florida Coast, Lynn K. Shay, Thomas M. Cook, Brian Haus, Jorge Martinez, Hartmut Peters, Arthur J. Mariano, John Vanleer, P. E. An, Samuel Smith, A. Soloviev, Robert H. Weisberg, Mark E. Luther
Vhf Radar Detects Oceanic Submesoscale Vortex Along Florida Coast, Lynn K. Shay, Thomas M. Cook, Brian Haus, Jorge Martinez, Hartmut Peters, Arthur J. Mariano, John Vanleer, P. E. An, Samuel Smith, A. Soloviev, Robert H. Weisberg, Mark E. Luther
Marine Science Faculty Publications
Escalating national interest in the coastal ocean underscores the need for high‐quality surface current data that can improve our understanding of surface circulation and its impact on societal and environmental issues related to coastal pollution, beach restoration, oil spill mitigation, and coastal air‐sea interaction. Coastal regimes exposed to strong ocean currents,surface waves, and winds during storm conditions may frequently require beach renourishment to restore valuable beaches that are key to local economies. Maintaining water quality is a problem, too, particularly where shipping dominates the traffic in and out of harbors. These environmental issues are increasingly difficult to manage due to …
Physical Factors Of Differentiation In Macrobenthic Communities Between Atoll Lagoons In The Central Tuamotu Archipelago (French Polynesia), Mehdi Adjeroud, Serge Andrefouet, Claude Payri, Joel Orempuller
Physical Factors Of Differentiation In Macrobenthic Communities Between Atoll Lagoons In The Central Tuamotu Archipelago (French Polynesia), Mehdi Adjeroud, Serge Andrefouet, Claude Payri, Joel Orempuller
Marine Science Faculty Publications
Nine atolls were characterized in order to understand how physical factors control the species composition, diversity, and abundance of macrobenthic (coral, mollusc, echinoderm, and algal) communities inside the lagoons. Only one region, the central part of Tuamotu Archipelago, French Polynesia, was considered, in order to minimise the variation due to regional factors between regions. The lagoons investigated showed a gradient of physical factors, providing various landscape configurations. The physical factors were surface area, abundance of pinnacles, degree of hydrodynamic aperture, and relative importance of passes in this degree of aperture. Macrobenthic communities were characterized by low diversity and strong dominance …
Extrinsic Con The Evolution Of Hawaiian Ocean Island Volcanoes, David A. Clague, Jacqueline E. Dixon
Extrinsic Con The Evolution Of Hawaiian Ocean Island Volcanoes, David A. Clague, Jacqueline E. Dixon
Marine Science Faculty Publications
Extrinsic parameters that affect the evolution of magmatic systems within and beneath ocean island volcanoes include physical variables such as confining pressure, which controls magma degassing, and temperature of the underlying lithosphere and crust, which controls magma crystallization during ascent. Other extrinsic parameters are environmental variables coupled to the hydrosphere and atmosphere such as hydrothermal circulation systems and even rainfall. All these extrinsic factors interact with intrinsic parameters, such as magma supply rates or composition, to modulate the evolution of magma chambers and the petrologic processes that take place within them.
Wind-Forced Reversing Jets In The Western Equatorial Pacific, Megan F. Cronin, Michael J. Mcphaden, Robert H. Weisberg
Wind-Forced Reversing Jets In The Western Equatorial Pacific, Megan F. Cronin, Michael J. Mcphaden, Robert H. Weisberg
Marine Science Faculty Publications
Upper-ocean zonal currents in the western equatorial Pacific are remarkably variable, changing direction both with time and depth. As a part of the Tropical Ocean and Global Atmosphere Coupled Ocean-Atmosphere Response Experiment, an enhanced monitoring array of moorings measured the upper-ocean velocity, temperature, salinity, and, surface meteorological conditions in the western equatorial Pacific for two years (March 1992-April 1994). Data from this array are used to evaluate the zonal momentum balance. Although nonlinear terms (zonal. meridional, and vertical advection) were at times large, reversing jets were primarily due to an interplay between wind forcing and compensating pressure gradients. In the …
Plankton Community Composition, Production, And Respiration In Relation To Dissolved Inorganic Carbon On The West Florida Shelf, April 1996, Gary L. Hitchcock, Gabriel A. Vargo, Mary-Lynn L. Dickson
Plankton Community Composition, Production, And Respiration In Relation To Dissolved Inorganic Carbon On The West Florida Shelf, April 1996, Gary L. Hitchcock, Gabriel A. Vargo, Mary-Lynn L. Dickson
Marine Science Faculty Publications
In April 1996 the Florida Shelf Lagrangian Experiment examined dissolved inorganic carbon (DIC) dynamics on the West Florida Shelf. DIC concentrations increased over 2 weeks at an average rate of 1 μmol kg−1 d−1 in a patch of the intentionally released tracers sulfur hexafluoride (SF6) and helium 3 (3He). Approximately 20% of the increase was due to air‐sea exchange with the remaining 80% attributed to plankton respiration [Wanninkhof et al., 1997]. Here we present particulate matter concentrations, phytoplankton production, and community respiration rates from the tracer patch that suggest that heterotrophs dominated …
Characteristics Of Wind-Generated Rings In The Eastern Tropical Pacific Ocean, Frank E. Muller-Karger, Cesar Fuentes-Yaco
Characteristics Of Wind-Generated Rings In The Eastern Tropical Pacific Ocean, Frank E. Muller-Karger, Cesar Fuentes-Yaco
Marine Science Faculty Publications
Eddies are generated in the eastern tropical Pacific (3 degrees S-23 degrees N, 75 degrees-105 degrees W) by winds blowing through Central American mountain passes from the Atlantic. We used Coastal Zone Color Scanner (CZCS) and advanced very high resolution radiometer (AVHRR) satellite imagery complemented with monthly in situ sea surface temperature and wind series from the Comprehensive Ocean-Atmosphere Data Set (COADS) to study these eddies and their effect on pigment concentrations in the region. Pigment values in the Gulf of Tehuantepec generally reach higher values in November-March before those in the Gulf of Papagayo. The eddies generated in the …
Micro- And Macrodiversity In Rbcl Sequences In Ambient Phytoplankton Populations From The Southeastern Gulf Of Mexico, John H. Paul, Albin Alfreider, Boris Wawrik
Micro- And Macrodiversity In Rbcl Sequences In Ambient Phytoplankton Populations From The Southeastern Gulf Of Mexico, John H. Paul, Albin Alfreider, Boris Wawrik
Marine Science Faculty Publications
Ribulose-1,5-diphosphate carboxylase/oxygenase (RuBisCO) large subunit genes (rbcL) were obtained by amplification and cloning of 554 or 614 bp sequences of indigenous phytoplankton populations at 2 stations in the southeastern Gulf of Mexico. One station (Stn 4) was located in a low salinity, high chlorophyll plume (the ŒGreen River¹) which has previously been shown to contain elevated levels of Form IA rbcL mRNA while the other (Stn 7) was in oligotrophic, oceanic water. A diversity of rbcL sequences was obtained, spanning 3 of the 4 evolutionary clades of Form I RuBisCOs. Six nucleotide sequences obtained from Stn 4 were …
Equatorial Upwelling In The Central Pacific Estimated From Moored Velocity Profilers, Robert H. Weisberg, Lin Qiao
Equatorial Upwelling In The Central Pacific Estimated From Moored Velocity Profilers, Robert H. Weisberg, Lin Qiao
Marine Science Faculty Publications
Horizontal divergence and vertical velocity (w) are estimated at 0°, 140°W using an array of five subsurface moored acoustic Doppler current profilers deployed from May 1990 to June 1991 during the Tropical Instability Wave Experiment. The record-length mean flow is divergent within the near-surface region and convergent within the thermocline, with maximum convergence located at the high speed core of the Equatorial Undercurrent (EUC). This pattern of divergence results in upwelling at and above the EUC core (with maximum value of 2.3 × 10−5 m s−1 located at 60-m depth) and downwelling below the core. The relative slopes in the …
The Recommended Dissociation Constants For Carbonic Acid In Seawater, Kitack Lee, Frank J. Millero, Robert H. Byrne, Richard A. Feely, Rik Wanninkhof
The Recommended Dissociation Constants For Carbonic Acid In Seawater, Kitack Lee, Frank J. Millero, Robert H. Byrne, Richard A. Feely, Rik Wanninkhof
Marine Science Faculty Publications
A coherent representation of carbonate dissociation constants and measured inorganic carbon species is essential for a wide range of environmentally important issues such as oceanic uptake of anthropogenic CO2 and carbon cycle depictions in ocean circulation models. Previous studies have shown varying degrees of discordance between calculated and measured CO2-system parameters. It is unclear if this is due to errors in thermodynamic models or in measurements. In this work, we address this issue using a large field dataset (15,300 water samples) covering all ocean basins. Our field data, obtained using laboratory-calibrated measurement protocols, are most consistent with …
Interannual Mean Sea Level Change And The Earth's Water Mass Budget, Don P. Chambers, Jianli Chen, R. Steven Nerem, Byron D. Tapley
Interannual Mean Sea Level Change And The Earth's Water Mass Budget, Don P. Chambers, Jianli Chen, R. Steven Nerem, Byron D. Tapley
Marine Science Faculty Publications
The relationship between interannual global mean sea level change and the Earth's water mass budget is examined between 1993 and 1998 by removing the steric (thermal) component from mean sea level computed with TOPEX/Poseidon (T/P) altimetry. The steric component is calculated from subsurface temperatures measured by expendable bathythermographs and interpolated to a global grid by empirical orthogonal function (EOF) reconstruction. Results indicate that from late-1995 to early-1998, the thermal expansion of sea level was significantly higher than the total sea level change measured by T/P, suggesting that fresh water mass was lost from the ocean. The size of the maximum …