2019年内蒙古雷电活动分析

Analysis of Lightning Activity in Inner Mongolia in 2019

基于闪电定位资料,文章对2019年内蒙古雷电活动进行了分析。结果表明:2019年内蒙古雷电活动最频繁的区域出现在兴安盟西南部与锡林郭勒盟东北部的交界地区,地闪密度可以达到21次/km2;内蒙古雷电活动存在明显的季节变化,雷电活动主要集中在5—9月,约占全年地闪总数的97.13%;尽管夏季雷电发生频次很多,但电流强度相对较小,相反的,冬季发生的雷电频次虽少,电流强度却较大。地闪频次的日变化总体呈现单峰型,峰值出现于15—16时;地闪强度平均值的日变化幅度不大。负地闪主要集中在10~30 kA,0~30 kA负地闪的累计概率可以达到65.89%,正地闪主要集中在25~40kA,不同强度区间的地闪频次差异不显著,0~50kA正地闪的累计概率为50.62%。

Based on the cloud to ground(CG) lightning data collected by location lightning detection net-work,the lightning activity in 2019 over the Inner Mongolia was analyzed.Results showed that the highest frequency of lightning activity in 2019 occurred over the border between the southwest of Hinggan League and the northeast of Xilingol League,with the ground lightning density reaching up to 21 times per square kilometers.Significant seasonal variation of the lightning is observed,with most lightning activities occurring during May to September,which accounts for 97.13% of the total number of annual ground lightning.Although the higher lightning frequency occurs in the summer of 2019,the current intensity during the summertime is relatively small.In contrast,fewer lightning activities occur in the winter but with much stronger current intensity.The diurnal variation of ground lightning frequency generally presents a unimodal pattern and maximizes from 3 to 4 p.m.However,the diurnal variation of the mean intensity of ground flash is small.Negative ground flashes are mainly concentrated in 10~30 kA,and the cumulative probability of 0~30 kA negative ground flashes accounts for 65.89% of the total negative ground flashes.Positive ground flashes are mainly concentrated in 25~40 kA,and there is no significant difference in ground flashes among different intensity intervals.The cumulative probability of 0 ~50 kA positive ground flashes is 50.62% of the total positive ground flashes.