太原夏季短时强降水与闪电的关系及应用  

作　　者：张泽秀 李梦军[1] 荆肖军[1] 

机构地区：[1]太原市气象局,太原030082

出　　处：《科技创新与应用》2024年第14期100-103,共4页Technology Innovation and Application

基　　金：山西省气象局气象科研项目(SXKQNDQ20185145);山西省气象局面上科研项目(SXKMSQH20205226)。

摘　　要：利用太原地区夏季三维闪电定位系统的2017—2021年闪电数据、小时降水量及国家站10 min降水量,分析短时强降水日的闪电特征,并将短时强降水站点与前1 h的闪电密度进行空间叠加。结果表明,短时强降水日闪电以负闪为主。负闪密度远大于正闪密度,且有明显的空间差异,负闪密度中心主要位于尖草坪北部和阳曲县南部。闪电频数峰值比10 min降水量峰值提前10~60 min,且闪电频数峰值(大于等于50次/10 min)及其后的20 min内闪电频数陡降其峰值的一半或以上,这对短时强降水有更好的指示作用。短时强降水站点与前1 h的闪电高密度区有很好的对应关系,且大多分布在闪电密度梯度相对较大的地区。当太原地区闪电频数大于100次/h时,闪电密度大于等于0.1次/km2·h对短时强降水落区预警命准率较高。Based on the lightning data of the three-dimensional lightning positioning system in Taiyuan and hourly precipitation from 2017 to 2021,as well as 10 min precipitation at the national station,the lightning characteristics of short-term torrential precipitation days are analyzed,and the short-term torrential precipitation stations are spatially superimposed with the lightning density of the previous hour.The results show that:The daily lightning of short-term torrential precipitation is mainly negative lightning.The negative flash density is much larger than the positive flash density,and there are obvious spatial differences.The negative flash density centers are mainly located in the north of Jiancaoping and the south of Yangqu County.The peak value of lightning frequency is 10~60 min earlier than that of 10 min precipitation,and the peak lightning frequency(≥50 times/10 min)and the steep decrease of lightning frequency in 20 min by half or more of its peak value are better indicators of short-term torrential precipitation.The short-term torrential precipitation stations have a good corresponding relationship with the lightning high density area in the previous hour,and most of them are distributed in the areas with relatively large lightning density gradient.When the lightning frequency in Taiyuan area is more than 100 times/h,the lightning density≥0.1 tiqmes/km2·h is more accurate for early warning of short-term torrential precipitation.

关 键 词：短时强降水 闪电特征 闪电密度 闪电密度指标 闪电频数 

分 类 号：P332.1[天文地球—水文科学]