历史时期以来山西省雪灾特征与气候变化

Characteristics of snow disaster in Shanxi Province and its climate change in historical period

通过对历史文献资料的搜集、整理与统计分析,利用最小二乘法、小波分析和空间Kriging插值等方法,对山西省历史时期(730BC-2000AD)以来雪灾的等级、发生时间(阶段、季节变化和周期等)和空间变化规律进行研究。结果表明:历史时期以来山西省共发生雪灾208次,平均13.125 a发生一次。其中,将雪灾划分为轻度、中度、重度三个等级,各占灾害总频次的16.83%、72.60%和10.58%;小波分析显示,雪灾存在5 a、23 a的周期变化,23 a左右的周期振荡最强。历史时期以来山西省雪灾呈波动上升趋势,阶段性特征明显,经历了频次较少-快速增加两个阶段;4月和冬季发生频次最高,分别占总数的15.76%和34.47%。雪灾发生频次空间差异大,南部发生的最多。初步确定,历史时期以来山西省雪灾的发生与气候的异常变化是密切相关的,明清时期雪灾发生频次最高;现代为雪灾发生的频发期,寒冷气候需进一步考证。

Based on the statistics and analysis of snow disasters in historical documents in Shanxi province during historical period, the temporal and spatial variations of snow disasters were obtained by using least squares, wavelet analysis and Kriging method. There are 208 recorded snow disasters in Shanxi province, approximately once every 13. 125 years on average. The mild, moderate and severe disasters accounted for 16.83%, 72. 60% and 10. 58%, respectively. Wavelet analysis showed that snow disasters had 5 and 23-year oscillation period and the disaster in Shanxi province showed an increasing 23-year oscillation period was the strongest. The snow trend during the historical period. In April and winter season, snow disasters occurred most frequently, accounting for 15.76% and 34.47% of the total, respectively. The spatial distribution of snow disaster was different, mostly distributed in southern area. It can be concluded that snow disasters were closely related to the climate change; snow disasters occurred most frequently during the Ming and Qing Dynasties; modern time is a period of frequent occurrence of snow disasters.