四川2008年“9．23”强对流天气中雷电活动和降水结构关系的研究

利用常规气象资料、地闪及TRMM卫星等资料，运用统计和对比的分析方法，对四川“9．23”雷暴过程中地闪的时空演变特征及其与降水结构的关系进行了研究分析。结果表明：沿副高边缘移动的“9．23”雷暴过程主要发生在川西高原以东地区，地闪空间分布集中连续，且主要以双单体雷暴系统的形式出现。处于雷暴系统或单体中心的地面站其地闪频数的峰值提前或同时与降水量峰值出现；而处于雷暴系统或单体边缘的地面站其地闪频数的峰值则更易滞后于降水量峰值。地闪的发生与雷暴云中的水成物粒子的分布状态都有直接的关联性，负地闪放电主要源于雷暴系统中较低的云水及可降水强中心区域，而正地闪放电则源于较高的云冰强中心的边缘处。

Study of Relationships between Thunderstorm activities and Precipitation Structure of the"9.23"Convective system in 2008 over Sichuan Province

By utilizing the data of conventional meteorology, the data of CG; lightning and TRMM satellite, the spatiotemporal evolution characters of CG lightning and relationships between CG lightning and precipitation structure which happened on ＂9.23＂ over Sichuan province have been analyzed according to statistics and comparison analysis methods. Results show as follows. The ＂9.23＂ thunderstorm which moved along the effect of subtropical high mainly occurred during nighttime east of Chuanxi Plateau, the special distribution of CG lightning is concentrated and continuous, and usually happened in the form of multi-cell. The peaks of CG lightning frequency often reach high values before （or at same time with） the arrival of the precipitation at the ground in center areas of thunderstorms or cells; while lag after that in edges of thunderstorms or cells. The occurrence of CG lightning is directly related to the distribution of the type of hydrometeors in thunderstorm cloud. Discharges of negative CG lightning are from the lower cloud or precipitate water center of thunderstorms, while ones of possitive CG lightning from the edge of cloud ice center.