关键词: 降水距平百分率, 降水距平百分率, 帕尔默干旱指数, CI干旱指数, 修订改进

Abstract: According to the lightning accident data in Beijing from 1957 to 2015, the relevant characteristics of lightning casualties were analyzed by using the mathematical statistics method. The results showed that: the recorded lightning casualty accidents were 65 in total, among which 47 persons were killed and 96 persons were injured, with personnel casualty ratio of 2.04:1 and an average of 2.42 persons per year. Lightning stroke accidents occurred from April to September, mainly from June to August, most of which were in July (accounting for 32.31%). The spatial distribution of lightning stroke was mainly in the central and eastern part of Beijing and Dongcheng district had the most lightning stroke accidents, which had a certain relationship with a relatively dense population and the concentration of tourist places. The lightning accidents causing personnel injury and death increased rapidly since 1990s, and simultaneously the casualty accidents in the suburb districts became more than that in urban districts. The location of lightning stroke distributed in the open area, accounting for 43.08% of the total locations as the largest category, followed by buildings, trees, mountains, farmland and water area, in that order. The most stroke type was direct lightning, accounting for 52.31%, followed by contact voltage, step voltage and flanking flashover. The Great Wall and the Capital Airport in recent years had more lightning accidents. The temporal and spatial distributions of thunderstorm day from 1959 to 2012 were compared, and the spatial distribution was somewhat different while the temporal distribution was somewhat similar. Finally, according to the characteristics of the personnel casualty accident, a practical and effective lightning protection equipment was designed, which could protect the personnel safety in open area.