海北雷暴活动分析

Analysis on Thunderstorms over Haibei

利用海北6个气象站1978～2007年30a气象观测资料和2000～2007年雷灾资料,从气象要素变化分析了海北地区雷暴日数时空变化的原因,并从地理和土壤环境背景角度分析了雷暴多发和雷灾多发的原因。结果表明,海北地区雷暴次数总的趋势是减少的,各地雷暴日数不同,门源为多雷区,托勒为少雷区;雷暴出现最多方位为西北方和西南方;雷暴活动的强弱与近地层大气的不稳定有关,地气温差的高低和相对湿度的大小与海北雷暴活动关系密切;气候变化是导致海北雷暴减少的主要因素之一;雷暴日数和雷击灾害的发生与当地所处的地理位置、盛行风向、土壤背景有关。

The reasons of the thunderstorms time and space change with the meteorological factors are analyzed by using the 30 years＇ （from 1978 to 2007） meteorological observational data and thunderstorms data from 2000 to 2007 in Haibei state, and the reasons for the thunderstorm disasters occurrence from the geological and soil background are also analyzed. The results show that the general trend of the thunderstorm frequencies are decreasing, and the thunderstorm days are different among the areas of Haihei state： Menyuan has the most and Tuole has the least. Most thunderstorms occur in the northwest and southwest. The intensities of thunderstorm activities are related with the unstable surface layer atmosphere; the rusticity temperature and relative humidity are closely related with the Halbei thunderstorm activities; The climatic change is one of the primary causes of reducing thunderstorms; The thunderstorm days and disasters are related to the geological location, prevailing wind direction and soil background.