Anomalies Of The North China Precipitation And The Relations With SSTA In North Pacific And The Anomalies Of 100hPa Height Field

Using the monthly precipitation data of the 160 Stations in China from 1951 to 2000, based on the analysis of the North China precipitation characters, this paper particularly discusses the reasons for the anomalies of North China precipitation and the influence of SSTA anomalies on summer precipitation in North China ,and primarily analyses the influence of the Anomalies of 100hPa Height Field above Tibetan Plateau. The main result may be concluded as follows:(l)The rainy season in North China is from June to September, and the main precipitation befallen in July and October.(2)Summer rainfall of North China exists periodic variation of quasi-three years and six years, and .spring, autumn and winter also exist periodic variation of quasi-three years.(3)In the recent fifty years, there is a significant drought tendency in summer and autumn ,slow increase tendency in spring and winter, and a drought tendency in annual precipitation of North China.(4)Summer rainfall anomalies in North China relates to the Indian summer monsoon, the South sea monsoon, Sub-tropical anticyclone, South Asian anticyclone and cold air anomaly.(5)There is a positive correlation between the summer precipitation in North China and the central of North Pacific SST from present January to present Match.(6) There is a negative correlation between the precipitation in flood season ( mean precipitation of July, and August) and 100hPa Height Field above Tibetan Plateau from former Match to May.