A simple model of evaporatively driven downdraft: application to microburst downdraft.

Abstract

A simple one-dimensional, time-dependent model of an evaporatively driven downdraft is presented. The model is described by equations for raindrop evaporation, raindrop concentration, water substance, thermodynamic energy and vertical air velocity. At the top of the downdraft, the pressure, temperature, relative humidity, vertical air velocity and the raindrop size distribution are specified; Marshall-Palmer and monodisperse drop size distributions are considered. -from Author Dept. of the Geophysical Sciences, The Univ. of Chicago, Chicago, IL 60637, USA.