凉山州闪电活动特征分析

凉山州位于四川省西南部,由于特殊的地理因素和大气环流季风气候,是全省雷暴日数最多的地区,每年所造成的损失严重。本文基于2005~2014年的闪电监测资料,分析了凉山州地区闪电的年、月、时变化及闪电密度和强度时空分布特征。分析结果,凉山地区闪电活动以负闪为主,占94.43%,正闪仅占5.57%;各县市正、负闪次数差异明显;闪电密度分布呈明显的地域性差异,相对较高区域主要分布自北向南以雅砻江、安宁河谷沿线的冕宁、越西、喜德、西昌、盐源、德昌、会理等县区域为主;6~9月为发生闪电的集中高发区月份,发生闪电数占全年闪电总数的86.53%,6月为闪电最高频发峰值,部分县闪电活动月分布存在一定的差异性;闪电时频度也存在一定差异变化;总闪强度主要集中5~30KA以下,累积概率为86.14%,其中5~20KA的闪电强度概率最高,平均为76.24%。 

Analysis of Lightning Activity in Liangshan

Liangshan is located in the southwest of Sichuan province. Because of the special geographical factors and the monsoon climate,it is the most severe thunderstorm days in the whole province. Based on lightning monitoring data from 2005 to 2014,the temporal and spatial distribution characteristics of lightning density and intensity in Liangshan area are analyzed in this paper. Analysis results,lightning activity in Liangshan area to negative flash based,accounting for change,positive lightning accounted for only 5. 57%; counties and cities of positive and negative lightning frequency difference; lightning density distribution was obvious regional difference,relative higher area mainly distributed from north to south in the Yalong River,the Anning River valley along Mianning,Yuexi,Xide,Xichang,Yanyuan,dechang,huili and county area mainly. 6-September lightning occurs from high incidence area in,lightning accounted for the annual total lightning 86. 53%,June lightning maximum frequent peak,the lightning activities of some county distribution exist certain differences; lightning frequency also exist certain difference; total lightning intensity is mainly concentrated below 5 ~ 30kA,cumulative probability for 86. 14%,of which 5 ~ 20kA lightning intensity probability was the highest and average 76. 24%.