HR: 09:00h
AN: OS51D-05    [Abstracts]
TI: On the Origin of Mesoscale Variability in the Caribbean Sea
AU: * Sheinbaum, J
EM: julios@cicese.mx
AF: Oceanografia Fisica,CICESE, Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja Calif, 22860, Mexico
AU: Jouanno, J
EM: jouanno@cicese.mx
AF: Oceanografia Fisica,CICESE, Km 107 Carretera Tijuana-Ensenada, Ensenada, Baja Calif, 22860, Mexico
AU: Barnier, B
EM: Bernard.Barnier@hmg.inpg.fr
AF: LEGI-CNRS, CNRS UMR 5519 BP53, 38041, Grenoble, cedex 9, France
AU: Molines, J
EM: Jean-Marc.Molines@hmg.inpg.fr
AF: LEGI-CNRS, CNRS UMR 5519 BP53, 38041, Grenoble, cedex 9, France
AB: The circulation in the Caribbean Sea is investigated using a two-way nested high resolution configuration of the Océan Parallélisé (OPA) primitive equation model that includes the North Atlantic (1/3 degree) and Intra- Americas Sea (1/15 degree resolution). Consistent with altimetry data, the simulations show a westward growth of baroclinic eddies with maxima of variability in the Colombia Basin. The mesoscale presents a westward shift from periods of 50 days near the Lesser Antilles to periods of 100 days in the Cayman Basin associated with the growth and merging of eddies. Energy diagnostics suggest that baroclinic instability is the dominant mechanism controlling the variability in the Venezuela/Colombia Basins whereas in the Cayman Basin, barotropic instability is more important. The broad scale flow of the southern branch of the Subtropical Gyre divides into two branches within the Caribbean. The southern branch merges with the return flow from the meridional overturning circulation conforming the main Caribbean Current close to the continental coast, with the northern branch flowing close to the southern boundary of the Greater Antilles. This flow separation is associated with enhanced potential vorticity gradients which explains why the flow is more prone to instability. Seasonal variations in eddy kinetic energy are also analyzed.
DE: 4512 Currents
DE: 4520 Eddies and mesoscale processes
DE: 4528 Fronts and jets
DE: 4534 Hydrodynamic modeling
DE: 4562 Topographic/bathymetric interactions
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly