1961—2010年中国降水量变化分区及其区域特征

The division of precipitation change and its regional characteristics in China during 1961—2010

为研究中国近50 a(1961—2010年)降水量变化的空间分区及其区域特征,利用598个气象站1961—2010年逐旬降水资料,计算各站的降水量距平百分率,通过经验正交函数(ROF)和旋转经验正交函数(REOF)对降水量变化进行空间分析,进而对中国50 a降水量变化特征进行分区,同时采用线性趋势分析及5 a滑动平均分析方法,分析了全区及各个分区降水量变化特征。结果表明:根据1961—1990年、1971—2000年和1981—2010年3个时段可分别将中国分成12、11和11个降水量变化区。综合3个时间段降水量变化特征,可将中国分为江淮地区、东北中南部地区、中国北部地区、新疆地区、江南和华南东部地区、黄淮地区、西南地区东部和江南西部地区、东北北部地区、华南中西部、青藏地区、西南地区西部11个区域。通过降水量变化特征分析,近50 a中国降水呈现减少趋势,且存在区域差异。降水量减少幅度最大的是黄淮地区,气候倾向率为-13.9415 mm·10 a^(-1),降水量增加幅度最大的是江南和华南东部地区,气候倾向率为23.2075 mm·10 a^(-1)。

In order to study the division of precipitation change and its regional characteristics in recent 50 years of China,using each ten days precipitation data from 598 meteorological stations during 1961—2010,the precipitation anomaly percentage of each station was calculated. Through the empirical orthogonal function and rotated empirical orthogonal function,carried out the spatial analysis for the precipitation change and division of the precipitation change characteristics in recent 50 years of China,also using the linear trend analysis and 5-years moving average analysis methods,the variation characteristics of precipitation in the whole region and each district were analyzed. The results indicated that: China can be divided into 12,11 and 11 change regions,respectively,according to the 1961—1990,1971—2000 and 1981—2010. Synthesized the precipitaion change characteristics in three time periods,whole China can be divided into 11 regions,such as Jianghuai region,Central and Southern Northeast region,Northern part of China,Xinjiang region,Southern and South Eastern region,Huanghuai region,Eastern of Southwest region and West of Southern regions,Northern part of the Northeast region,Midwest of South China,Qinghai-Tibet region,West of the Southwest region.Through the analysis of the precipitaion change characteristics,the precipitation was tended to decrease in recent 50 years of China,but presented regional difference. The maximal precipitation decreasing trend was in Huanghuai region,and the climatic trend rate was-0.0183 mm·10 a^(-1). While the most obvious increase tendency of precipitation was occurred in Southern and south eastern region,the climatic trend rate was 23.2075 mm·10 a^(-1).