Abstract:

Lightning is a strange atmospheric phenomenon, which causes great damage to human society. Lightning has become one of the ten most serious natural disasters announced by the United Nations. The research of lightning disasters helps to better understand their features, impacts and causal factors, from which the relevant measures for lightning protection could be taken to induce the injuries and economic losses. Recently research of lightning disasters is playing a more and more important role in lightning disasters evaluation and lightning risk assessment. In the past 20 years, there were lots of lightning disasters in Anhui Province and some of them caused great damage such as great injuries and economic losses. According to the data of the lightning disasters from 1998 to 2012 and the data from lightning location system in Anhui Province, characteristics of the lightning disasters and their relevant causes were analyzed statistically, showing that a lot of factors should be taken into account for lightning disaster causes such as regional lightning activities, level of regional lightning protection, level of economic development in different areas. The results show that during these years, lightning disasters were of higher incidence from 2002 to 2009. Lightning disasters mostly occurred in June, July and August; distribution of monthly percentage of lightning disasters in Anhui Province has good consistency with lightning. Cities suffered from more lightning disasters than villages. In addition, dominating losses caused by lightning in villages were mainly casualties while those in cities were mainly economic loss and physical damages to electronic equipment. Annual frequency of lightning disasters in 78 counties was counted; more lightning disasters appeared in central and south Anhui Province, a possible reason is that there are more lightning in these areas. Based on those data, average lightning density had better correlation to annual frequency of lightning disasters than the average lightning intensity in counties. Civilian facilities, electric power and communication are main loss industries in all 16 cities caused by lightning in Anhui Province, loss of some regional economy industries are also serious. In order to characterize the affecting extent resulting from lightning disasters in different areas, annual frequency of lightning disasters N, average annual number of casualties M and average annual economic loss E were selected as evaluation indices to present a comprehensive assessment for the lightning disasters in 78 counties of Anhui province, with the entropy weight synthetic evaluation model used for natural disaster assessment. Comprehensive disaster index G of 78 counties is divided into 3 levels by using the equalinterval method. Furthermore, synthetic index G is obtained to reflect the severity caused by the lightning disasters in different areas and space distribution for lightning disaster intensity was classified. The result shows that Nanling, Fuyang, Maanshang, Huaibei and Xuancheng are heavy lightning disaster areas, so more lightning protection measures need to be taken in these areas. The evaluation results can provide scientific basis for regional lightning protection and risk assessment