浙江省地闪特征及致灾危险性分析  

Analysis of CG Lightning Characteristics and Disaster-Causing Risk in Zhejiang Province

作　　者：顾媛 张卫斌 崔雪东 GU Yuan;ZHANG Weibin;CUI Xuedong(Zhejiang Meteorological Safety Technology Center,Hangzhou 310008)

机构地区：[1]浙江省气象安全技术中心,杭州310008

出　　处：《气象科技》2021年第4期654-661,共8页Meteorological Science and Technology

基　　金：浙江省气象科技计划项目(2018QN03)资助。

摘　　要：基于2007-2018年浙江省ADTD闪电监测资料,分析该区域地闪时空分布特征,进而选用地闪密度和强度作为致灾要素,进行致灾危险性评估。结果表明:落雷日数和正地闪比例的年际变化均呈增长趋势,全年地闪集中发生于6-9月的12:00-20:00。春季正地闪比例高,地闪多发于傍晚和夜间;夏季日地闪落雷面积广、密度极值高,午后雷暴占主导地位。地闪密度相对高值区随季节演变而自西向东移动,年平均地闪密度总体呈浙中多南北少的特征。雷电流幅值主要分布于15~45kA,地闪强度平均值在舟山最高(44.49kA),台州最低(32.69kA),地闪密度和强度的空间分布特征各异。致灾危险性极高等级在浙东沿海一带和杭州—绍兴交界呈片状分布,另在温州西北部、浙中和浙西地区呈絮状分布,致灾危险性与历史雷灾个数、人员伤亡总数的空间分布总体一致。Based on the observation data of the Zhejiang ADTD lightning location system(from 2007 to2018),the spatial and temporal distribution characteristics of cloud-to-ground(CG)lightning are analyzed.Considering both CG lightning density and intensity,an analysis of lightning disaster causing risk is made.The results show that the number of thunderstorm days per year and the percentage of positive CG lightning each year both have a rising tendency during the 12 years.The CG flashes mainly occur from 12:00 to 20:00,June to September.In spring,the proportion of positive CG lightning is much higher,while the most of flashes occur in the evening and at night.In summer,there are many abnormally high values of daily lightning density and lightning area,while the peak hour of daily lightning is mainly in the afternoon.The spatial distribution of higher CG lightning density area varies from west to east with season changes.It is also found that the average CG lightning density over the years is higher in the central Zhejiang than in north and south parts.The amplitude of CG lightning current is mainly distributed from 15 to 45 kA.The average value of CG lightning intensity is the highest in Zhoushan(44.49 kA),while the lowest in Taizhou(32.69 kA).The spatial distribution characteristics of lightning intensity and density are different.It suggests that the very high lightning disaster-causing risk level locates in the coastal area of the eastern Zhejiang,Hangzhou-Shaoxing border,northwestern Wenzhou,central Zhejiang and western Zhejiang.The spatial distribution characteristics of disaster causing risk level are consistent with the number of historical lightning disasters as well as the total number of casualties.

关 键 词：地闪 时空分布 致灾因子 地闪强度 

分 类 号：P429[天文地球—大气科学及气象学]