HR: 18:05h
AN: OS54A-08    [Abstracts]
TI: The Bottom Boundary Layer in the Deep Gulf of Mexico
AU: * Badan, A
EM: abadan@cicese.mx
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AU: Rivas, D
EM: drivas@cicese.mx
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AU: Ochoa, J
EM: jochoa@cicese.mx
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AU: Candela, J
EM: jcandela@cicese.mx
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AU: Sheinbaum, J
EM: julios@cicese.mx
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AU: Mouton, J
EM: moutonjo@ensieta.fr
AF: Oceanografía Física, CICESE, Apdo. Postal 2732, Ensenada, BC 22800, Mexico
AB: A year-long time series of current profiles, upward from ten meters off the bottom in 3750 m of water in the central Gulf of Mexico, shows that the measuring range of the instrument, and the velocity of the current in the boundary layer vary as a function of time, the former because the concentration of backscattering suspended matter fluctuates with the strength of the currents above the boundary layer. Therefore, currents near the bottom, typically of O(0.1 m·sec^-1) are often strong enough to cause sediment resuspensions. Estimates of the thickness of the boundary layer based on the friction velocity support the notion of an active boundary layer that varies with the bottom-intensified motions of the lower, very homogeneous, layers of the Gulf of Mexico. The deeper layers in the gulf have been shown to be actively ventilated and therefore highly oxygenated. Hence, organic matter near the bottom must be efficiently oxidized. The dynamical and environmental implications of these findings are discussed.
DE: 4223 Descriptive and regional oceanography
DE: 4277 Time series experiments (1872, 3270, 4475)
DE: 4520 Eddies and mesoscale processes
DE: 4804 Benthic processes, benthos (0408)
DE: 4863 Sedimentation (1861)
SC: Ocean Sciences [OS]
MN: 2007 Joint Assembly