济南市近50年雷暴气候特征分析

利用1960～2009年济南6测站雷暴观测资料,从雷暴日数年月分布和雷暴初终日变化趋势及初终日的绝对变率、相对变率等方面进行了分析,深入了解济南市雷暴发生的气候规律以及演变趋势。从年际变化来看,济南市雷暴日数整体呈减少趋势,济南站年平均雷暴日数在均值附近波动,其余各站年平均雷暴日数线性倾向率为-2.5～-3.9d/10a。雷暴只发生在3～11月,6～8月是雷暴多发期,7月雷暴最多,8月次之。中部山前平原较北部冲击平原和南部丘陵山区雷暴初日出现偏早,而雷暴终日结束偏晚,初终间日数延长;南部丘陵雷暴初日、终日均较平原区稳定。

Climatic Characteristics of Thunderstorm in Ji'nan in the Last 50 Years

By using thunderstorm data of Ji’nan six stations,variance trends of yearly and monthly thunderstorm days were analyzed including variance trends of the first and the last thunderstorm days and their absolute variability and opposite variability to investigate the climatic characteristics of thunderstorm and its evolving trend in Ji’nan area.As seen by inter-annual variation,thunderstorm days in Ji’nan City reduced as a whole,annual mean thunderstorm days of Ji’nan station undulated with its mean value,while annual mean thunderstorm days of other stations reduced with a linear inclination rate of-2.5～-3.9 d/10 a.Thunderstorm only occured from March to November and the frequent thunderstorm period was from June to August most was July,next was August.The first thunderstorm day over submountain plain in mid-region was the earlier than that in north alluvial plain or south hilly land,while the last thunderstorm day of it was the latest so that thunderstorm period over submountain plain was longer.Either the first thunderstorm days or the last thunderstorm days in south hilly land were stable compared to plain terrain.