西北师范大学学报（自然科学版）

基于1978—2013年人工雷暴日和2007—2020年闪电定位仪雷电监测数据,分析雷暴日、雷击点密度、地闪强度的区域分布以及雷暴日、地闪频率的年、月、日变化特征,通过雷击点密度、地闪强度、雷暴日数等资料综合评估宁夏雷电致灾危险性的区域分布.结果表明,宁夏雷暴日呈现“山地多、川区少,南北多、中部少”的地域分布特征,六盘山和贺兰山相对于其他地区属于雷暴日高发地带,这说明雷暴的发生与地形、地势密切相关;雷暴日和地闪都具有明显的年、月、季、日变化特征,峰谷波动周期为3～5年,7,8月份站全年地闪68.9%,是地闪的高发月份,一天中13～23时是地闪高发时段,雷电流幅值主要集中在10～60 k A;宁夏北部、东部和南部地区为雷电致灾危险性高到较高风险等级区域,其中贺兰山沿山、盐池县北部、麻黄山、六盘山区为雷电致灾危险性高风险等级区域.

Based on the artificial thunderstorm day data from 1978 to 2013 and the lightning monitoring data from lightning location instruments from 2007 to 2020,this study analyzes the regional distribution of thunderstorm days,lightning strike point density,and ground flash intensity,as well as the annual,monthly,and diurnal variation characteristics of thunderstorm days and ground flash frequency.By comprehensively evaluating the regional distribution of lightninginduced disaster risk in Ningxia using data such as lightning strike point density,ground flash intensity,and the number of thunderstorm days,the results show that:The thunderstorm days in Ningxia exhibit a regional distribution characterized by “more in mountainous areas,fewer in river plains;more in the south and north,fewer in the central part.”The Liupan Mountains and Helan Mountains are high-frequency thunderstorm areas compared to other regions,indicating that the occurrence of thunderstorms is closely related to terrain and topography.Both thunderstorm days and ground flashes have distinct annual,monthly,seasonal,and diurnal variation characteristics,with peak-to-trough fluctuation cycles of 3 to 5 years.July and August account for 68.9% of the annual ground flashes,making them the peak months for ground flashes.The period from BF13:00 to 23:00 is the high-incidence time for ground flashes within a day,and the amplitude of lightning current mainly concentrates between 10 kA and 60 k A.The northern,eastern,and southern regions of Ningxia are areas with high to relatively high risk levels of lightning-induced disasters,among which the areas along the Helan Mountains,northern Yanchi County,Mahuang Mountain,and the Liupan Mountain area are identified as high-risk areas for lightning-induced disasters.