基于ArcGIS的雷电致灾危险性分析 ——以内蒙古为例

Analysis of spatial characteristics of lightning disaster-causing risk in Inner Mongolia based on ArcGIS

摘要:

基于内蒙古自治区2014—2023年闪电定位数据,利用spss数理统计分析法、百分位数法、层次分析法和AcrGIS中的空间分析法,研究了内蒙古雷电活动特征及其致灾危险性的空间特征。结果表明:内蒙古落雷日数呈增长趋势,总闪和负闪密度呈下降趋势,正闪密度呈上升趋势,通过T检验,在0.05置信水平以上具有显著性。5—9月是闪电高发期,7月闪电活动最为活跃。上午7~10时(北京时,下同)闪电活动最弱,午后13~19时闪电活动最为活跃。正闪电流幅值显著高于负闪,从下四分位数至上四分位数,正负闪电流幅值的比值大约从1.7增加至2.0,中位数和平均值正闪约为负闪的1.8倍。雷电致灾危险性呈现为在大兴安岭准南北走向以东和阴山山脉准东西走向以南,由平原—河谷—山地逐渐增高的态势。高值区主要位于呼伦贝尔市、兴安盟、通辽市、包头市南部、乌兰察布市南部、呼和浩特市和鄂尔多斯市。

Abstract:

Based on the lightning location data of Inner Mongolia from 2014 to 2023, the spatial characteristics of lightning activity and its hazard in Inner Mongolia were studied by using spss mathematical statistics analysis method, percentile method, analytic hierarchy process and spatial analysis method in AcrGIS.The results show that the flash days shows an upward trend, the total flash and negative flash density show a downward trend, and the positive flash density shows an upward trend. Through the T test, it is significant above the 0.05 confidence level. May-September is the high incidence period of lightning, and the lightning is the most active in July. The lightning is the weakest at 7-10 a.m., and the lightning is the most active at 13-19 p.m. The trend of the average peak current of lightning is opposite to the trend of lightning activity. The peak current of positive flashes is significantly higher than that of negative flashes. From the lower quartile to the upper quartile, the ratio of positive and negative flash peak current increases from about 1.7 times to 2.0 times, and the median and average positive flashes are about 1.8 times that of negative flashes. The lightning disaster-causing risk is gradually increasing from the plain-valley-mountain area in the east-west direction of the Yinshan Mountains to the south and the north-south direction of the daxing"an mountains to the east.