强对流云人工增雨和防雹原理的二维数值研究

THE 2-D NUMERICAL STUDY OF RAIN-EN-HANCEMENT AND HAIL-SUPPRESSION PRINCIPLES ON CONVECTIVE CLOUDS

本文建立了一个二维深对流云数值模式,用该模式模拟了一个实测强对流云个例。其结果同观测相近。本文做了一系列催化数值试验,结果表明:在云发展早期播入高浓度的人工冰晶胚胎,能促使云中产生大量的大冰晶和小霰粒,它们争食液水,不易长成大雷,地面降雹动能可减少45％,但降雨量也有明显减小;减小播撒剂量,催化效果亦减小,防雹和增雨效果不明显;若在云发展早期引进浓度为10~0-10^(-1)/L的小雨滴,则能明显提早和增加降水。对于不同强度的对流云,人工引晶仅对中等积云(云顶高为6—8km)的增雨效果较好。文中还比较了二维和一维的模拟结果。

In this paper, a 2-D deep convective cloud model is presented and used to simulate a real storm case. The calculation results are agreeable with observations. Based on it, a series seeding experiments are done in order to decrease hailfall and/or enhance rainfall. The seeding results are analysed and compured with 1-D simulations.