福建西部山区短时暴雨雷达回波特征及中小尺度系统分析

摘要

Utilizing conventional meteorological data,T-Inp and the Longyan and Jianyang CINRAD/SA data,the radar echo characteristics and meso-microscale systems of short-time rainstorms in western mountainous area of Fujian are analyzed.The results show that the short-time torrential rainfall echoes can be classified for continental convective precipitation and tropical marine precipitation.Besides,the rela-tionship between the convective precipitation,the tropical marine precipitation’s low level reflectivity fac-tor and rainfall intensity are statistically analyzed.The rainfall echoes are classified for local developed stagnation echo and“train effect”echo which constantly affects certain regions according to the impact time of rainfalls.Based on the evolution of radar echoes,base velocities and weather systems,three types of meso-microscale systems which lead to short-time rainstorms are extracted.The first is meso-scale shear line or convergence line related to low-level shear line (trough)and southwest jet.The second is low-level shear line or convergence line which moves to south.The third is adverse wind area or mesocylone related to local convections.%利用常规天气资料、探空、地面降水资料以及建阳、龙岩两部新一代天气雷达资料对2005-2009年福建西部山区短时暴雨的雷达回波特征及对应的中小尺度系统进行分析，分析表明：短时暴雨的雷达回波按降水类型可分为大陆强对流型降水和热带海洋型强降水，并统计了大陆强对流型降水和热带海洋型降水低层反射率因子与雨强对应关系；按降水影响时间可以分为以局地发展为主的停滞型回波和不断影响某一地区的移动型列车效应回波；利用雷达回波演变及基本径向速度资料，结合天气系统，提取三类产生短时暴雨对应的中小尺度系统：与低空切变（或低压槽）、西南急流配合的中小尺度切变线或辐合线，以切变南压为主的中小尺度切变线或辐合线和以局地对流发展为主的逆风区或中气旋。