【摘要】 相对于全球性的持续变暖趋势,降水量变化格局及其区域分异有更大的不确定性,因此研究不同区域降水量的变化特征是当前全球气候变化研究的重要内容之一。本研究基于1951~2002年中国约730个气象台站观测数据,利用空间插值和Mann-Kendall时间序列趋势分析方法并结合GIS技术,分析了过去50多年中国降水量的时空变化特征。结果表明,全国平均年降水量从60年代到90年代呈明显下降趋势,但在90年代后期出现回升,其中夏季和冬季降水量已达到50年代和60年代的水平。同时,降水量变化呈现显著的区域分异特征:华北、华中、东北南部地区持续下降,长江流域以南地区明显增加,而新疆北部、东北北部和青藏高原西部60年代到70年代下降,80年代后期有所回升。中国北方有从干旱到湿润转变的迹象,但华北和东北南部地区仍然处于持续的干旱期。中国降水量的总体下降及90年代后期的回升与全球变化趋势基本一致,但区域变化格局与全球中高纬度地区降水增加、热带和亚热带地区减少的特征正好相反。更多还原

【Abstract】 Under the background of global climate change,there are even greater uncertainties of the precipitation changing trend and regional differences.Therefore,it is one of the most important frontier fields of presently global change research to study the changing characteristics of precipitation in different regions.In this study,we analyzed the spatio-temporal patterns of precipitation in China during 1951 to 2002 by using spatial spline interpolation method and Mann-Kendall trend test,also with the support of GIS,based on measurements at about 730 meteorological stations nationally.The results showed that there was an obvious decreasing trend from the 1960s to the 1990s in China,and a recovery occurred in the late 1990s,while in summer and winter precipitation was comparable with that in the 1950s and the 1960s. Furthermore,results showed that precipitation presented clear regional spatial differences in the analyzed period: In North China,Central China,and southern Northeast China,precipitation reduced persistently in the period we studied,while sharp increase occurred in the south of the Yangtze Valley,and in northern Xinjiang,northern Northeast China,and western Tibet,precipitation decreased from the 1960s to the 1970s,and had a relative recovery in the 1980s.While climate in northern China appeared to have a sign of turning from dry to wet,and North China,Northeast China Plain still have been at the stage of drying which began since the mid 1960s.On the whole,the total declining trend of precipitation in China was comparable with that of global in the analyzed period,but regional variation patterns were opposite from global that precipitation increased obviously in the middle and high latitude regions,and decreased in the tropical and semi-tropical regions.更多还原