湖北省两次区域性暴雨过程的对比分析  

Contrastive Analysis of Two Heavy Rain Cases in Hubei Province

作　　者：施望芝[1] 张萍萍[1] 吴涛[1] 钟敏[1] 韩琦[1] 

机构地区：[1]武汉中心气象台,武汉430074

出　　处：《暴雨灾害》2008年第3期219-224,共6页Torrential Rain and Disasters

基　　金：中国气象局新技术推广项目"江淮流域实时洪水预报中水文气象耦合方法研究"资助

摘　　要：利用常规气象观测资料和T213数值预报产品等资料,采用天气动力学诊断方法,对2007年春夏之交湖北省的两场区域性暴雨的相同点和不同点进行了诊断分析。结果表明:两次暴雨过程具有相似的环流背景及强低层辐合、高层辐散的动力学结构,且都受到冷空气的影响;两次暴雨过程的不同点在于,后一次暴雨过程的副热带高压、西南风急流明显强过前一次暴雨过程,前一次暴雨过程的地面冷空气强度和移速强于后一次暴雨过程;两次暴雨过程均伴随有能量锋区、湿度锋区,但后一次暴雨过程的能量锋、湿度锋、上升运动等明显强于前一次暴雨过程;前一次暴雨的雷达回波带结构不完整,强回波局地性较强,对应暴雨分布相对零散,后一次暴雨的雷达回波带结构紧密,回波组织性较强,对应暴雨站点较为集中;前一次暴雨的云系由多个云团合并形成,呈带状,对应暴雨站点分散、暴雨集中区域小,后一次暴雨的云系由一个微小云团发展而成,呈团状,其结构密实且停滞少动,对应暴雨区域较大且集中、大暴雨站点多。By using synoptic and dynamical diagnostic methods, the contrastive analysis of two heavy rain cases is performed with routine data and T213 products. It is shown that the two processes have the same circulation background, the same dynamic structure with air convergence in lower level and air divergence in upper level and are affected by the cold air. The differences between two cases are that the subtropical high and southwest wind＇s jet in the second heavy progress are obviously stronger than those in the first one, but cold air＇s intensity and speed in the ground of the first progress are stronger than the second progress＇. Both energy frontal zone and moisture front exist in two processes, but the energy frontal zone, moisture front and the ascending motion of the second progress are stronger than those of the first one. In addition, the incomplete echo structure of the first progress is corresponed with the scattered distribution of rainstorm , but the dense and strong structure of the radar echo in the second progress with the centralized distribution of rain storm. The characteristics of the cloud images indicate that multiple cloud clusters distributed in belts of the first process result in dispersed regional rainstorm, but the cloud system of the second process developed from a small cloud cluster appearing mass, dense and less active makes the large and concentrated regional rainstorm.

关 键 词：暴雨 物理量场 雷达回波 卫星云图 

分 类 号：P458.121[天文地球—大气科学及气象学]