HR: 10:40h
AN: A12D-02 INVITED    [Abstracts]
TI: Modeling the Upper Ocean Response to a Hurricane.
AU: * Price, J F
EM: jprice@whoi.edu
AF: Woods Hole Oceanographic Institution, Clark Laboratory, Woods Hole, MA 02543, United States
AB: The upper ocean response to a hurricane is a three-dimensional and time-dependent phenomenon that can be analyzed usefully from several different perspectives. From a (numerical) modeling perspective, a significant issue is whether a given phenomenon is resolved by an ocean model (and model hurricane) or has to be parameterized. Ocean models suitable for coupled air-sea forecasting applications will likely have a horizontal and vertical resolution of about 5 km and 10 m. Resolved phenomena will then include a hurricane-scale rightward bias of the surface current amplitude, and the downward and outward propagation of near inertial- frequency energy. Parameterized phenomena include diapycnal mixing within the upper ocean. This mixing determines the effective depth of the ocean surface layer and is the main contributor to the cooling of SST that is thought to be an important aspect of air-sea interaction. Evidence from the CBLAST deployment of EM-Apex floats is that this mixing is a response to stratified shear flow instability. The rightward bias of SST cooling is then a direct result of the rightward bias of the current amplitude. Satellite infrared images show a very clear signature of a rightward bias in SST cooling. They also show a significant along-track variability of SST cooling on scales of tens of kilometers whose origin is unclear. Certainly this kind of variability is not reproduced by ocean models forced by smoothly varying model hurricanes and started with homogeneous ocean initial conditions.
DE: 3374 Tropical meteorology
DE: 4504 Air/sea interactions (0312, 3339)
DE: 4572 Upper ocean and mixed layer processes
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting