Study of the possibility of stimulating precipitation from warm convective clouds by hygroscopic particles from numerical simulation

Abstract

We present the results of numerical simulation of the action of hygroscopic particles on a convective cloud for obtaining additional precipitation. The correspondence of vertical profiles of cloud parameters to those actually observed under natural atmospheric conditions is achieved within a one-dimensional numerical model by parametrization of the process of heat and moisture entrainment into the upward air flow forming the cloud. The model describes in detail microphysical processes in a cloud with the use of the kinetic equation for the size distribution of cloud droplets. The processes of forming precipitation in convective clouds with a vertical thickness of 3–4 km during their natural development and during the introduction of hygroscopic particles are analyzed using numerical calculations. It is shown that it is actually possible to obtain additional precipitation from convective clouds of continental type under the action of hygroscopic particles with sizes of 1–1.5 μm. The results of calculating the intensity and total amount of precipitation as functions of the vertical thickness of a cloud and the parameters of particles introduced into it are presented. The conditions necessary for obtaining the maximum positive effect are elucidated.