江西省雷灾灾情和闪电活动时空分布特征及灾情等级划分研究

Research on the characteristics of lightning disasters and lightning activities spatial and temporal distribution and the classification of disaster levels in Jiangxi Province

基于江西省雷电灾害数据和闪电监测数据,对比分析雷电灾害和闪电活动的时空分布特征,利用ArcGIS软件,绘制江西省各地市的雷击事故分布图和年平均雷击密度分布图;采用灰色定权聚类分析法,评估各地市的雷灾灾情等级和雷灾灾害风险等级,绘制江西省各地市的雷电灾害等级划分图和雷灾灾害风险等级划分图,对比分析评估结果。研究表明,雷击事故和闪电活动的时空分布特征有明显的一致性,集中发生时段是6~8月份、16时;雷击密度高值区和年平均雷击密度高值区有一定的对应关系,赣北地区雷击事故密度要高于赣南地区,农田、建(构)筑物和野外(空旷处)发生雷击伤亡事故最多,农村发生的雷击伤亡事故占总雷击事故数的85.16%。对比分析各地市雷灾灾情等级和雷灾灾害风险等级的评估结果可知,二者的匹配度达到45%,重灾区和高风险地区不相匹配,中灾区、中风险地区和少灾区、低风险地区较匹配,基于雷灾数据分析得到的灾情等级要比基于闪电监测数据得到的雷灾灾害风险等级要低一些,在实际防雷减灾工作中,可结合考虑二者的分布特征,采取相应减灾措施。

Based on the lightning disaster data and lightning monitoring data in Jiangxi Province,the temporal and spatial distribution characteristics of lightning disasters and lightning activities are comparatively analyzed.The lightning accident distribution maps and annual average lightning strike density distribution maps in various cities are drawn by ArcGIS software.Besides,the lightning disaster level and lightning disaster risk level of each city are evaluated by means of gray fixed weight aggregation class analysis method and the lightning division map and the lightning disaster risk division map are drawn too by ArcGIS software.In addition,the evaluation results of disaster levels are compared and analyzed.Studies have shown that the temporal and spatial distribution characteristics of lightning accidents and activities have obvious consistency,and the concentrated occurrence period is June to August,at 16:00;the areas with high lightning strike density and the areas with high annual average lightning strike density have a certain degree of consistency.According to the corresponding relationship,the density of lightning accidents in northern is higher than that in southern,and the number of lightning casualties in farmland,buildings(structures)and in the field(open areas)is the most.Lightning casualties in rural areas accounted for 85.16%of the total lightning accidents.A comparative analysis of the lightning disaster level and the lightning disaster risk level of various cities show that the matching degree between the two is 45%.The severely-hit area and the high-risk area do not match;the medium-hit area,the medium-risk area and the less-hit area,and the low-risk area are matched to a certain extent.And the disaster level based on lightning disaster data analysis is lower than the lightning disaster risk level based on lightning monitoring data.In actual lightning prevention and mitigation work,the distribution characteristics of the two can be combined to take corresponding disaster reduction.