梅雨锋云系中尺度系统回波结构及其与暴雨的关系

梅雨锋云系中中尺度回波带主要有对流带和混合带二种类型,中尺度回波团一般为混合型回波。对流云回波带在初生、成熟和消散三个不同的演变阶段结构特征不同,下垫面对回波带的演变有一定的影响。中尺度系统能够产生高强度降水,多个中尺度系统相继通过一地或中尺度系统与对流回波群的汇集可以造成梅雨期的局地性暴雨和大暴雨。产生暴雨的中尺度系统常具有混合型回波结构,它们降水强度大,对降水的贡献也大。

ECHO STRUCTURE OF MESOSCALE SYSTEMS IN THE MEI-YU FRONTAL CLOUD SYSTEM AND THEIR RELATIONS WITH THE HEAVY RAINFALL

In the Mei-Yu frontal cloud system. there are two kinds of meso-scale systems: meso-scale echo bands and meso-scale echo groups. Echo band consisting of convective clouds has different echo structure in different.evolution stages. Water surface and mountains have an effect on it's evolution. Analysis of precipitation shows that if several meso-scale systems pass successively through a place, or meso-scale echo bands and echo groups converge at the place, there will be local heavy rainfall. Also, meso-scale systems producing heavy rain are pf mixed cloud types, in which stratiform clouds and convective clouds coexist.