内蒙古雷灾特征及灾情的灰色关联评估

Characteristics and grey association evaluation of lightning disaster in Inner Mongolia

基于中国气象局1998—2008年《全国雷电灾害汇编》资料和内蒙古115个气象站的逐日雷暴观测资料,运用数理统计和灰色关联等方法分析了内蒙古雷电灾害特征。结果表明,内蒙古年雷电灾害次数总体呈上升趋势,雷电灾害次数月分布呈单峰型,与其雷暴日数的月分布基本一致;内蒙古雷电灾害次数、直接经济损失、伤亡人数、行业灾害特征等具有明显的区域性,呈"东部多西部少"特征;从行业雷电灾害特征来看,石油化工及矿业部门遭受的雷电灾害直接经济损失最大,居民用户发生雷电灾害次数最多;雷灾致人员伤亡地点多发生在农村牧区,其雷击伤亡人数占总伤亡人数的62.4%。最后运用灰色关联度方法对内蒙古各地区的雷电灾害进行了损失评估,内蒙古各盟市雷灾主要属于轻灾或微灾等级。

The present paper is aimed to introduce our systematic analysis of the characteristic features of the lightning disasters for the decade from 1998 to 2008 registered by China Meteorological Administration and the statistical data of the thunderstorm observational data provided by the 115 stations in Inner Mongolia autonomous region from 1971 to 2007. And then, we have made a comprehensive evaluation of such disasters in the region by means of mathematical statistics and grey association method based on the historical archives of nationwide typical cases of lightning disasters. The results of our analysis show that there exists an increasing trend of the number of the lightning disasters in the region in the above said corresponding periods. More specifically speaking, the monthly distribution of lightning disasters coincides with the monthly distribution of thunderstorms in a single peak type. At the same time, we have analyzed the temporal and spatial variation characteristics of lightning, the direct consequential economic loss and the degrees of fatalities, the afflicted industrial and agricultural installations and facilities, the distribution characteristics of lightning types and the discrepancy between the afflicted urban and rural areas, while stressing the regional differences. For example, each index in the eastern Inner Mongolia proves higher than that in the western. The industrial urban areas afflicted by the lightning disasters indicate that the average economic loss in the petro-chemical industry and mining sectors directly caused by lightning proves to be highest, with its most serious economic loss in the residential living installations. Moreover, the gravest lightning strike sites lie in the farmland and pastoral areas. It is just for this reason that it is necessary for the local people to pay greater attention to the agricultural and pastoral facilities and installations likely to be hit by the lightning, whose rate tends to be added up to 62.4% of the total number of casualties. And, finally, we have established a lightning disaster and loss assessment model for the entire autonomous region via the gray correlation degree method. The results of trial application of our the model proves to be rational for the lightning disaster grade area division and distribution thanks to our thorough control of the main influential factors for the different risk areas. One more point that should be added is that among the various areas likely to be hit by lightning and thunder-storms, the urban areas should be put into the lighter or minor disaster-hit ones.