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Interannual Volume Variability In The Tropical Pacific, Christina L. Holland, Gary T. Mitchum

Marine Science Faculty Publications

The question of whether or not the volume of the tropical Pacific changes over the course of an El Niño event has potentially important consequences for our understanding of the dynamical mechanisms responsible for El Niño‐Southern Oscillation (ENSO) events. In this study, we examine the volume variability of the tropical Pacific, defined as the areal integral of the sea surface height variability, using TOPEX/Poseidon altimetric sea surface heights and the output of a numerical model. We find that volume gradually builds up in the tropical Pacific prior to a typical ENSO event and rapidly decreases during the event due to …

Large Scale Ocean Circulation From The Grace Ggm01 Geoid, B. D. Tapley, D. Chambers, S. Bettadpur, J. C. Ries

Marine Science Faculty Publications

The GRACE Gravity Model 01 (GGM01), computed from 111 days of GRACE K-band ranging (KBR) data, is differenced from a global mean sea surface (MSS) computed from a decade of satellite altimetry to determine a mean dynamic ocean topography (DOT). As a test of the GGM01 gravity model, large-scale zonal and meridional surface geostrophic currents are computed from the topography and are compared with those derived from a mean hydrographic surface. Reduction in residual RMS between the two by 30–60% (and increased correlation) indicates that the GGM01 geoid represents a dramatic improvement over older geoid models, which were developed from …

Ocean Observer Study: A Proposed National Asset To Augment The Future U. S. Operational Satellite System, John D. Cunningham, Don P. Chambers, Curtiss O. Davis, Andrew Gerber, Rosalind Hetz, James P. Mcguire, William Pichel

Marine Science Faculty Publications

The next generation of U.S. polar orbiting environmental satellites, are now under development. These satellites, jointly developed by the Department of Defense (DoD), the Department of Commerce (DOC), and the National Aeronautics and Space Administration (NASA), will be known as the National Polar-orbiting Operational Environmental Satellite System (NPOESS). It is expected that the first of these satellites will be launched in 2010. NPOESS has been designed to meet the operational needs of the U.S. civilian meteorological, environmental, climatic, and space environmental remote sensing programs, and the Global Military Space and Geophysical Environmental remote sensing programs. This system, however, did not …

Phytoplankton Response To Intrusions Of Slope Water On The West Florida Shelf: Models And Observations, John J. Walsh, Robert H. Weisberg, Dwight A. Dieterle, Ruoying He, Brian P. Darrow, Jason K. Jolliff, Kristen M. Lester, Gabriel A. Vargo, Gary J. Kirkpatrick, Kent A. Fanning, Tracy T. Sutton, Ann E. Jochens, Douglas C. Biggs, Bisman Nababan, Chuanmin Hu, Frank E. Muller-Karger

Marine Science Faculty Publications

Previous hypotheses had suggested that upwelled intrusions of nutrient‐rich Gulf of Mexico slope water onto the West Florida Shelf (WFS) led to formation of red tides of Karenia brevis. However, coupled biophysical models of (1) wind‐ and buoyancy‐driven circulation, (2) three phytoplankton groups (diatoms, K. brevis, and microflagellates), (3) these slope water supplies of nitrate and silicate, and (4) selective grazing stress by copepods and protozoans found that diatoms won in one 1998 case of no light limitation by colored dissolved organic matter (CDOM). The diatoms lost to K. brevis during another CDOM case of the models. In …

Local And Deep-Ocean Forcing Contributions To Anomalous Water Properties On The West Florida Shelf, Robert H. Weisberg, Ruoying He

Marine Science Faculty Publications

Material property distributions on continental shelves result from the mixing and modifications of estuarine and deep-ocean source waters. How this occurs depends on the momentum and buoyancy that are input either locally on the shelf or from the deep-ocean at the shelf break. We address this question of local versus deep-ocean forcing for the West Florida Shelf (WFS) using in situ data and a numerical circulation model. The spring and summer seasons of 1998 and 1999 show distinctively different water properties on the shelf and at the shelf break. We account for these differences by a combination of local forcing, …

Millennial- To Century-Scale Variability In Gulf Of Mexico Holocene Climate Records, R. Z. Poore, H. J. Dowsett, S. Verardo, Terrence M. Quinn

Marine Science Faculty Publications

Proxy records from two piston cores in the Gulf of Mexico (GOM) provide a detailed (50–100 year resolution) record of climate variability over the last 14,000 years. Long‐term (millennial‐scale) trends and changes are related to the transition from glacial to interglacial conditions and movement of the average position of the Intertropical Convergence Zone (ITCZ) related to orbital forcing. The δ¹⁸O of the surface‐dwelling planktic foraminifer Globigerinoides ruber show negative excursions between 14 and 10.2 ka (radiocarbon years) that reflect influx of meltwater into the western GOM during melting of the Laurentide Ice Sheet. The relative abundance of the …

Assessment Of Current And New Methods For Investigating The Occurrence Of Enteric Pathogens In Ambient Waters And Water Sources For Rehydration Of A Floridan Wetland, Walter Quintero-Betancourt

USF Tampa Graduate Theses and Dissertations

Water quality assessment is currently used for determining the risks from contamination with waterborne pathogenic microorganisms. The public health. significance of such microorganisms cannot be fully understood without the application of reliable environmental monitoring techniques that provide efficient recovery as well as information on the infectious potential of specific isolates. This research was carried out to assess the analytical performance of current and new methods for investigating the occurrence of waterborne Cryptosporidium oocysts in samples of surface water, groundwater and reclaimed water used for public access irrigation in the State of Florida.

Method 1623 of the U.S Environmental Protection Agency …

Evaluation Of Automated Ribotyping As A Tool For Bacterial Source Tracking In Aquatic Environments, Tracy L. Idocks

USF Tampa Graduate Theses and Dissertations

An Escherichia coli ribotype profile library was created for the Tampa Bay watershed for application to bacterial source tracking of human or non-human fecal contamination to the bay and surrounding rivers. Bacterial source tracking uses a variety of methods to identify the source of fecal contamination, not just the quantity of the indicator bacteria present, allowing implementation of effective management practices. The 700 confirmed E. coli isolate library was equally distributed among four sources: human, bird, dog and cow. The library was tested for applicability for source tracking within the Tampa Bay watershed. The DuPont Qualicon RiboPrinter® Microbial Characterization System, …

Chlorophyll Dispersal By Eddy-Eddy Interactions In The Gulf Of Mexico, M. Toner, A. D. Kirwan, A. C. Poje, L. H. Kantha, Frank E. Muller-Karger, C. K. R. T. Jones

Marine Science Faculty Publications

A Lagrangian analysis of the transport and dispersal of plumes observed in satellite‐derived ocean color images was conducted using a data‐assimilating model of the Gulf of Mexico. The interaction between pervasive cyclonic and anticyclonic eddies in the Gulf generated advective paths that connect remote shelf regions. These paths aligned remarkably well with the plume events recorded with the chlorophyll‐a ocean color product from SeaWiFS. Two such events were studied. In one event material was transported in a thin strip between the northern wall of the Loop Current and an adjacent cyclone, connecting the eastern Campheche shelf (off the Yucatan Peninsula) …

A Loop Current Intrusion Case Study On The West Florida Shelf, Ruoying He, Robert H. Weisberg

Marine Science Faculty Publications

The Gulf of Mexico Loop Current intruded upon the West Florida continental shelf in June 2000. In situ currents and hydrography along with satellite temperature and altimetry measurements are used to describe this event and its effects on the shelf. A strong southward current is observed to flow along the shelf slope seaward of the intruded water boundary. This current transported cold, nutrient-rich water from the north, thereby producing anomalous hydrographic features near the shelf break (80-m isobath). An array of moored velocity profilers reveals that the currents landward of the intruded water are independent of the Loop Current and …