长治市近40a寒潮气候特征分析

Anaalysis on the characteristics of cold wave of Changzhi in the last 40 years

利用1969年-2008年长治市11个地面气象站的气温资料，应用对比分析和小波分析方法，对寒潮分布特征进行了综合分析，结果表明：①长治市的寒潮发生时段为9月至次年5月；最早平均时间为9月13日，最晚平均为5月18日；24h寒潮发生次数较多的是1月、4月，48h寒潮发生次数较多的是1月、10月和12月，5月和9月寒潮出现较少；总体上平川多于山地，峡谷多于盆地。②寒潮总次数存在明显的7a-8a和14a周期变化，寒潮结束期和开始期分别存在10a和7a周期，而且两者的20a周期也较为显著。③随着气候的变暖，寒潮次数、寒潮开始期和结束期分别呈现出减少、推后和提前的趋势。

Based on the air temperature data from 11 ground meteorological stations in Changzhi during 1979-2008, the distribution characteristics of cold wave in Changzhi were analyzed with contrast analysis and wavelet analysis methods. The results indicated that the cold wave happened from September to next May, and the earliest occurrence date was September 13th, while the latest end date was May 18th. The 24h cold wave occurred most frequently in January and April, while 48h cold wave occurred most frequently in January, October and December. The frequency of cold wave was the lowest in May and September. The cold wave frequency decreased from the plains to the mountain areas and decreased from the valleys to the basins. There are 7-8 years and 14 years two significant periods of cold wave total times, as well the periods of end time with 10 years and start time with 7 years ,moreover their 20 years period is also more obvious. Along with the climate warming, cold wave times reduces, initial period delays and end period advances.