河南省2005年7月22日大暴雨过程数值模拟与诊断分析

Numerical Simulation and Diagnostic Analysis of a Heavy Rainstorm Process in Henan on 22 July 2005

利用MM5V3.6版中尺度非静力模式,对2005年5号台风海棠减弱为低压倒槽后于7月22日在河南造成的大暴雨天气进行数值模拟和诊断分析,结果表明:强降水发生前大暴雨区上空深厚湿层和不稳定层结已经形成;在高低层同时出现的正负涡度柱、散度柱耦合结构及其互耦配置和剧烈的上升运动,导致不稳定能量快速释放,产生大暴雨。

Based on the nonhydrostatic mesoscale numerical model MM5(V3.6),the heavy rainstorm in Henan on 22 July 2005,when the 0505 typhoon Haitang weakened and developed as inverted trough of low depress,was simulated and diagnostic analyzed.The results show that deep humid level and unstable stratification had formed before the heavy rainstorm took place.Positive and negative vorticity columns all appearing in high and low level,coupling structure of divergence columns,allocation of coupling structure and strenuous ascending motion,leaded to fast release instability energy and rainstorm ultimately.