一次由降水引发地质灾害的降雨过程模拟及诊断分析

Simulation and Diagnostic Analysis of A Rainfall Process of Geological Disasters Caused by Precipitation

利用再分析资料、探空资料以及多普勒天气雷达资料,对2021年6月云南大理白族自治州一次引发地质灾害的降雨过程进行诊断分析,并结合数值模式,对观测资料的诊断结果做验证。结果表明:此次降雨过程主要是受滇缅高压和副热带高压之间的季风槽影响,季风槽东移有利于引导低层水汽输送;切变线南压,有助于低空动力抬升,配合冷平流的作用,触发对流性降水天气;数值模拟试验进一步验证和再现了此次降雨过程的基本特征,与观测资料的诊断结果一致。

The reanalysis data,sounding data and Doppler weather radar data were used to diagnose and analyze a rainfall process that caused geological disasters in Dali Bai Autonomous Prefecture of Yunnan Province in June 2021,and the diagnostic results of the observation data were verified by numerical model.The results show that the rainfall process was mainly affected by the monsoon trough between the Yunnan-Myanmar High and the subtropical high,and the eastward movement of the monsoon trough was conducive to guiding the water vapor transport in the lower layer.The southward pressure of the shear line was conducive to the dynamic uplift of the low altitude,and the cold advection triggers the convective precipitation weather.The numerical simulation test further verified and reproduced the basic characteristics of the rainfall process,which was consistent with the diagnostic results of the observation data.