基于ADTD型闪电定位数据的江门闪电特征

利用广东省ADTD(active divectory topology diagrammer)闪电定位系统资料,分析2017-2019年江门地区地闪回击的时空分布特征.结果表明:地闪密度大值分布在江门北部及西部,中部地闪回击密度最低.正地闪回击频次占总回击频次的3.36％,负地闪回击频次占总回击频次的96.64％;月分...

Characteristics of Lightning in Jiangmen Based on the Data of ADTD,a Locating Device for Lightning

Using the data of an active directory topology diagrammer,a locating device for lightning in Guangdong province,this work analyzes the spatiotemporal distribution of cloud-to-ground(C-G)lightning return stroke currents in the area of Jiangmen from 2017 to 2019.The results are shown as follows.For cloud-to-ground(C-G)lightning,large densities are distributed in the north and west part and minimum densities are in the central part of the city.The frequency of positive C-G lightning return strokes takes up 3.36%and that of negative ones amounts to 96.64%of the total.Monthly distribution is mainly from May to September,with most active C-G lightning in June,July and August.For the time of the day,it happens most frequently from 12:00 to 17:00.The intensity of positive C-G lightning return stroke currents is mostly within 20 and 60 kA with an annual average of 51.3 kA,and that of negative and total ones concentrates in the range from 10 to 50 kA with annual averages of 37.0 kA and 37.4 kA,respectively.Furthermore,the average intensity of C-G lightning is higher during the night than in daytime.For the monthly variation,the intensity of both positive and negative C-G lightning is smooth,with the maximum diurnal distribution all in a few hours before sunrise and the minimum from the afternoon to the time close to sunset.