THE INFLUENCE OF THE PROCESS OF PRECIPITATION ON THE STRUCTURE OF LOCAL CUMULUS

Taking consideration of the feedback on the vertical motion due to the drag force and the cooling effect acted on the air by raindrops, a system of differecitial equations for the vertical velocity, temperature difference between cloud and environment and the water.content is introduced. The solutions are analysed numerically for five sets of different parameters. From the analysis the effect of different intensity of precipitation, stratification, initial condition and environment are studied, and it is further found that under the influence of precipitation process, the vertical velocity, temperature difference and water content in cloud are reduced very quickly, and the descending motion appeas rapidly first at the cloud base, then spreads upward. Thus, starting from the cloud base, the cloud dissipates rapidly. This resembles the observed process of the dissipation of a precipitating cloud.