中国黄土高原地区降水时空演变

为揭示黄土高原地区降水资源在全球气候变化背景下的演变特征,利用黄土高原地区7省区51站43 a的降水资料,主要采用EOF、CEOF和小波分析等方法,研究了黄土高原降水近43 a的时空演变及其资源信息在空间的流动。结果表明：黄土高原年季降水对全球变化区域响应不同;年降水和秋季降水在1985年附近发生气候突变,降水明显减少;降水年际变化存在2～4 a振荡和11～18 a的年代际振荡,以2～4 a短周期振荡为主;降水响应敏感区在黄土高原腹地,空间演变信息在向东传播。

Spatial-temporal Evolution of Precipitation in China Loess Plateau

For the purpose of discovering the evolution characteristics of precipitation resource in Loess Plateau under the global climate change circumstances, its spatial-temporal evolution and the information flow during the recent 43 years have been studied by methods of EOF, CEOF and wavelet analysis based on the 43 years precipitation data of 51 meteorological stations over 7 provinces in Loess Plateau. The results showed that the yearly and seasonal precipitation responses to the global climate change differ in different regions in Loess Plateau. The yearly and the autumn precipitation decreased abruptly at about 1985. The yearly variation existed simultaneously the periods of 2-4 years and 11-18 years, but with the former as the predomi nant. The hinterland of Loess Plateau is the sensitive area of precipitation responding to global change; the spatial evolution information spreads to the east.