摘要
用EOF分析方法选取西北地区29个代表站,分别对其春季和夏季近50a降水进行年际变化和年代际变化时空特征分析,发现西北地区近50a降水时空趋势变化以103°E为基准线,以西为正,以东为负,并有准3a的振荡周期;20世纪80年代中期西北地区春季降水出现了气候突变,西北地区多、少雨与500hPa高度场和副热带高压的位置和强弱密切相关。
29 representative stations in Northwest China are selected using EOF analysis,and the temporal and spatial characteristics of the interannual and interdecadal variations of 50-year spring and summer precipitation are analyzed.It is found that the tendency of precipitation in northwest China is positive to the west of 103°E longitude and negative to the east.And there are a quasi-three years periodic oscillation of precipitation and a sudden change in the spring precipitation in the middle 1980's in northwest China.The above results indicate that the wet/dry phase of climate in northwest China is close related with the 500hPa height field and the location and intensity of subtropical high.
出处
《南京气象学院学报》
CSCD
北大核心
2004年第3期336-346,共11页
Journal of Nanjing Institute of Meteorology
基金
国家自然科学基金资助项目(40233037)
国家自然科学基金资助项目(40175021)
关键词
西北地区
降水异常
合成分析
Northwest China
precipitation anomalies
composite analysis