REGIONAL CHARACTERISTICS OF SUMMER PRECIPITATION ANOMALIES OVER CHINA

The regional characteristics of precipitation anomalies of total summer precipitation of June,July and August and individual monthly precipitation are analyzed by using the method of VarimaxEOF and correlation analysis.The data set used is the precipitation of a 5°Lat.×5°Long.spatialuniform network over China in the period of 1959 to 1994.The analysis of total summer precipitation shows that the most significant regionalcharacteristic is the existence of negative correlation in precipitation anomalies between the lowerreaches of the Changjiang River and the Huaihe River Valley(the LRCH region)and the middlereaches of the Huanghe River Valley(the MRH region),and between the LRCH region and SouthChina.The precipitation anomaly over the Sichuan Basin is negatively correlated with that overeastern part of Qinghai-Xizang Plateau and that over the LRCH region.The regionalcharacteristics of summer precipitation anomalies in western China are that there exists negativecorrelation between the summer precipitation anomalies over the southern part of the central andeastern Qinghai-Xizang Plateau and that over its northern part.There also exists positivecorrelation between the southern part of the central and eastern Qinghai-Xizang Plateau and theeastern part of North China and the southern part of Northeast China.The above spatialcorrelation modes have significant periods of about 3 years and ten years.The analysis of themonthly precipitation shows that in June there exists positive correlation among the precipitationanomalies over the LRCH region,the eastern part of North China and Northeast China.In July,the precipitations in the MRH region and the LRCH region are negatively correlated.The regionalcharacteristic of precipitation anomalies in August is very similar to that of the total summerprecipitation anomalies.

REGIONAL CHARACTERISTICS OF SUMMER PRECIPITATION ANOMALIES OVER CHINA