HR: 11:45h
AN: OS22A-06    [Abstracts]
TI: Redistribution of riverine water along the continental shelves of the northern and western Gulf of Mexico
AU: * Morey, S L
EM: morey@coaps.fsu.edu
AF: Center for Ocean - Atmospheric Prediction Studies, Florida State University, Tallahassee, FL 32306-2840 United States
AU: O'Brien, J J
EM: jim.obrien@coaps.fsu.edu
AF: Center for Ocean - Atmospheric Prediction Studies, Florida State University, Tallahassee, FL 32306-2840 United States
AU: Zavala-Hidalgo, J
EM: jzavala@troposfera.atmosfcu.unam.mx
AF: Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico Cd. Universitaria , Mexico, DF 04510 Mexico
AB: The seasonal variability of circulation on the continental shelves of the northern and western Gulf of Mexico is explained using observational data and a high-resolution numerical model. It is shown that the primarily wind driven circulation governs the salinity field on the shelves, by transporting low salinity water formed by river discharge along seasonally shifting pathways. When buoyant low salinity water is present over the outer continental shelf near the shelf edge, it is available for entrainment in currents associated with the mesosocale eddy field of the Gulf. The preferred locations for this cross-shelf export of fresh water shift seasonally as the shelf circulation transports low salinity water along shelf, and impact the upper ocean salinity field throughout the Gulf. A low salinity tongue is found in the monthly climatology in the Bay of Campeche during the winter months, and another extends southeastward from De Soto Canyon along the eastern edge of the Loop Current during the summer. A similar pattern can be seen in the monthly climatology chlorophyll concentration produced from remotely sensed ocean color data, suggesting that the biological properties of the surface waters of the Gulf may be controlled by this combined wind-driven shelf circulation and eddy interaction mechanism responsible for redistributing river discharged fresh water.
DE: 4219 Continental shelf processes
DE: 4243 Marginal and semienclosed seas
DE: 4255 Numerical modeling
SC: Ocean Sciences [OS]
MN: 2005 Joint Assembly