两次雷暴的地闪及降水宏微观特征  

Macroscopic and microscopic characteristics of CG lightning and precipitation in two thunderstorms

作　　者：周筠珺[1,2] 瞿婞[1] 李展[1] 李哲[1] 胡初阳 

机构地区：[1]成都信息工程学院大气科学学院,成都610225 [2]中国科学院大气物理研究所中层大气与全球环境探测实验室,北京100029 [3]西藏气象台,拉萨850000

出　　处：《气象科学》2010年第6期791-800,共10页Journal of the Meteorological Sciences

基　　金：中国科学院知识创新工程领域前沿项目(IAP09314);灾害天气国家重点实验室开放课程(2010LASW-A08);西藏强对流天气短时临近预报预警系统项目;成都信息工程学院科研基金项目(CRF200903)

摘　　要：用地闪及TRMM卫星等资料,分析四川两次长生命期雷暴的地闪及降水的宏微观特征。结果表明:在"副高边缘效应"及高空槽的影响下,两次雷暴均主要发生于夜间的川西高原以东地区,且主要以多单体系统及单体的形式出现。宏观上,雷暴系统或单体中心区地闪频数峰值提前或同步于降水量峰值出现;而于雷暴系统或单体边缘区地闪频数峰值则易滞后于降水量峰值。雷暴微物理结构上看,两次过程中的双单体或单体雷暴基本可等效为双极性电荷结构,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。雷暴中正、负地闪的比率分别与云冰及云水区域距离地面的位置有着直接的联系。By using the data of CG lightning and TRMM satellite,the macroscopic and microscopic characteristics of CG lightning and precipitation in two thunderstorms over Sichuan province have been analyzed.Two thunderstorms with multi-cell and single cell mainly occurred during nighttime in the east of Chuanxi Plateau due to ＂the edge effect of subtropical high＂ and upper-level trough.Based on macroscopic analysis,peaks of CG lightning frequency often reach high values before or simultaneously with the arrival of the precipitation on the ground in the center areas of thunderstorms or cells;but they are later than the precipitation peak in the edges of thunderstorms or cells.After analyzing the relationship between microphysical structures and CG lightning in two thunderstorms,it can be concluded that the charge structures of dual-cell and single cell are basically equivalent to dipoles.Discharges of negative CG lightning come from the lower cloud or precipitable water center of thunderstorms,while ones of positive CG lightning come from the edge of cloud ice center.The ratios of positive and negative CG lightning directly relate with the distances from cloud ice or water areas to ground surface respectively.

关 键 词：雷暴 地闪 降水 TRMM 

分 类 号：P427.32[天文地球—大气科学及气象学]