Sea-surface flow in the northeast Gulf of Mexico using surface drifter, TOPEX/ERS altimetry, and NOAA/AVHRR data

The surface flow near the shelf in the northeastern Gulf of Mexico (NEGOM) was examined using monthly mean NOAA/AVHRR sea-surface temperature (SST) data, TOPEX/ERS sea-surface height (SSH) data, and surface current data from drifters released in 1996 and tracked by the NOAA/ARGOS tracking system. From January through July, the shelf-break flow in the DeSoto Canyon region was eastward and southward in the west Florida Shelf region. The shelf-break circulation was jetlike and anticyclonic, following the curvature of the shelf off the Florida Panhandle region. In August, a flow reversed and the mean shelf-break surface currents were northward off the west Florida Shelf, westward in the DeSoto Canyon region, and offshore in the Mississippi Delta region. This gave the flow a cyclonic curvature. Potential forcing functions for the observed circulation patterns are discussed.