The mutual response of the tropical squall line and the ocean

The Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) is used t o investigate the mutual response of a tropical squall line and the ocean. Simulated squall line compares well with the observations, and consists of counterrotating vortices, and has a bow shape bulge toward the leading edge . In addition to these features, which are also shown in the:he previous nu merical simulations, the unique results from the coupled simulation indicat e that the:he air-sea interaction processes within the squall line are impo rtant. They affect both the atmosphere and the ocean locally. Simulated upp er ocean displays significant response to the squall line with upwelling an d baroclinicity. Depth of the ocean mixed layer in the coupled simulation b ecomes modified due to feedback processes. Ocean temperature acts as a dest abilizing factor, and the salinity as a stabilizing factor. Surface turbule nt fluxes from the coupled simulation are about 10% less than that of the u ncoupled simulation. The SST in the coupled simulation decreases by about 0 .21 degrees C. Predicted squall line in the coupled simulation is weaker as compared to the uncoupled simulation. This is reflected in terms of differ ences in surface fluxes, cloud water, rain water and vertical velocities be tween the two simulations.