Abstract ATM-9313588 Esbensen, Steven K. Mahrt, Larry J. Oregon State University Title: Tropical Atmospheric Boundary Layers Physical and dynamical processes the regulate the air-sea exchange of sensible heat flux, water vapor and momentum will be analyzed using new data sets from the TOGA (Tropical Ocean Global Atmosphere) Program. The proposed research is intended to contribute to a better understanding of the coupled ocean- atmosphere system and to provide an observational basis for improving representations of the marine atmospheric boundary layer in dynamical prediction models of the atmosphere-ocean system. The project has two specific objectives: o determine quantitatively the effect of spatial variations due to mesoscale and synoptic scale disturbances on the large- scale averaged air-sea flux fields of sensible heat, water vapor and momentum over the equatorial Pacific Ocean o improve bulk aerodynamic formulas for spatially averaged fluxes including weak wind conditions through analysis of aircraft data from TOGA COARE (Coupled Ocean-Atmosphere Response Experiment) and moored buoy data from the TOGA-TAO (Tropical Ocean Atmosphere) array. This research is important because it seeks to quantify the physical exchange between the warm waters of the western Pacific Ocean and the overlying atmosphere in a highly climate sensitive region of the world.