Simple parameterizations of the marine boundary layer are a crucial component of numerical models of weather and climate. In the tropics and subtropics, tradewind cumulus clouds are by far the most common cloud type. Parameterizations of trade cumulus cloud fields rely heavily on correctly predicting the vertical mass and moisture fluxes within individual cumulus clouds, yet these predictions have not been adequately compared with either observations nor models of individual cumuli. Using data from the previously executed Hawaiian Rainband Project, the Principal Investigator will analyze dual-Doppler data of trade cumuli in order to determine the vertical profile of vertical mass fluxes throughout the life cycle of a large number of individual precipitating cumulus clouds. The Principal Investigator will utilize a three-dimensional numerical boundary layer cloud model to help in interpretation of the results from the Doppler radars. He also will compare results from both observations and the numerical model to currently used parameterizations of trade cumulus cloud fields.
