| Based on the analysis of the Northeast China precipitation character, thispaper is particularly concerned with the corresponding general circulation anomalies character of the Precipitation in Spring and in Summer in Northwest China and the influence of SSTA in middle-east equator Pacific Ocean .29 representative stations of Northwest China are selected using EOF analysis, and the detailed results of characteristics are given for temporal and space variation of interarmual change and decadal change. The main conclusions are followed:(1) the tendency of precipitation in northwest China is positive to the west of 103°E longitude and opposite to the east of it. There is a periodic oscillation of quasi-three years of precipitation and a mutation in the middle of 80s in spring precipitation of northwest China.(2) It indicates the close relationship between wet, dry phase and the position, amplitude of 500hPa high field and subtropical high. And there are close relation with polar vortex ,south Asia high field.(3) The spring precipitation anomalies are close relation with the same attitude areas, and negative correlation with Northeast ones. If there are much rain in summer, then the lands which are from sea are rainy, otherwise the areas nearly sea are rainy.(4) There is a apparent positive correlation between spring precipitation in northwest China and SSTA(8~9 monthly averaged in former year)in middle-east equator pacific Ocean, especially the higher correlation in the 'Key regions' (125° W~85°W\ 5°S~10°N) .(5) There is a apparent positive correlation between summer precipitation in northwest China and SSTA(7~9 monthly averaged in former year)in middle-east equator pacific Ocean, especially the higher correlation in the 'Key regions' (150° W~110°W, 15°S~5°N) .(6) There is a positive couple correlation between spring and summer precipitation in northwest China and SSTA by SVD analysis.
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