A Two-Cylinder Model of Cumulus Cells and Its Application in Computing Cumulus Transports

Abstract

A two-cylinder model suitable for computing vertical transports in cumulus cells is formulated. The model includes explicit computation of perturbation pressure and allows the study of the evolution of raindrop size spectra. Sensitivity tests were performed to determine the response of the model to different assumptions. Analysis of the moisture and heat budgets yields information on the effect of cumulus convection on the larger scale environment. Results of applying the model to a computation of heat and mass transports by cumulus cells are presented. Comparison of the present results for Boston in the month of July with those obtained by Houze (1973) indicates that the two models give comparable total heat transports in the region of the cloud column. The level of maximum heat transport is noticeably lower in the present computation.