舟曲“8.8”特大山洪泥石流灾害气象成因分析

Analysis on the Meteorological Causes for the 8 August 2010 Massive Mudslide in Zhouqu,Gansu Province

本文利用气象监测数据分析了2010年8月8日凌晨发生在甘肃省舟曲县的特大山洪泥石流灾害的气象成因。经过分析表明,造成此次特大山洪泥石流的主要气象触发因素是一场局地性强、短时强度大、突发性强的短历时强降雨型的强对流天气过程;经过雷达、卫星资料分析,其天气系统具有明显的中尺度特征;这种中尺度天气系统的发生、发展是在高空有冷空气东移南下的大尺度环流背景下,由低层切变线天气系统强迫作用造成的。

By using the meteorological monitoring data,the meteorological causes for the massive mudslide in Zhouqu which occurred on 8 August 2010 are analyzed.Results demonstrate that the severe convective weather process with heavy precipitation is the main cause for this massive mudslide.The characteristics of this heavy precipitation are local,large intensity in short time and paroxysmal.The data of radar and satellites suggest that the weather system has obviously mesoscale characteristics.This kind of mesoscale weather system is produced by the forcing of the shear line in the low level,when the cold air in the high level is moving eastward and southward.