山西省气候变化的多尺度诊断

利用山西省108个地面气象站1957-2003年逐月降水、平均气温以及蒸发量等气象要素资料,采用主成分分析和聚类分析法进行气候分区,选取10个代表站的降水和平均气温序列,运用Morlet小波分析方法,对山西省47年气候变化以及不同时间尺度降水和气温变化的空间差异进行了诊断分析.结果表明:①山西省降水和气温存在多层次结构,不同时间尺度,存在不同的周期振荡行为.②山西省降水和气温总的变化趋势是20世纪80年代中期以前变冷变湿,且变化剧烈,之后变暖变干,且变化趋于缓和;21世纪初降水有恢复性增加趋势,气温有回落迹象.③山西省降水的空间差异明显,而气温变化的空间差异则相对较小.④从季节分布来看,21世纪初,春季降水偏少,冬季偏多,夏秋季降水则为偏少趋势中有小幅增加阶段;春季气温仍为偏高趋势,秋季有回落迹象,冬夏季为偏高趋势中有小幅回落阶段.

Study on Climate Change at Multi-temporal Scales in Shanxi Province

In this paper,the climate change and the spatial difference of the change of precipitation and air temperature at different temporal scales in Shanxi Province since recent 47 years are lucubrated based on the data of monthly precipitation, evaporation and mean air temperature from 108 meteorological stations during the period of 1957-2003 as well as the series of the change of precipitation and mean temperature from 10 representative meteorological stations using principal component analysis,cluster analysis and Morlet wavelet analysis.The results are mainly as follows:(1) There are the multi-hiberarchy structures in precipitation and temperature and the different periodical fluctuations at different temporal scales in Shanxi Province;(2) The climate change in the province was characterized by cold-wetting trend before the mid-1980s,and then warming-drying trend;precipitation has been in an increase trend but temperature in a decrease trend since the beginning of this century;(3) The spatial difference in precipitation change in the province is significant,but that in temperature is relatively low;(4) In seasonal distribution,precipitation in spring has been in a decrease trend since the beginning of this century,that in winter in an increase trend,and that in summer and autumn in a slight increase trend;temperature in spring has been in an increase trend,that in autumn in a decrease trend,and that in winter and summer in a slight decrease trend.