| The lack of water resource over North China in Spring having severely heldback further development of production in industry and agriculture and influenced continual development of economics is an important problem to be settled for later economic development over North China. Former people have developed abundant research of drought and flood in Summer, but have less research of that in Spring and respective month over North China. In this article, Based on the rainfall data over North China in spring and respective month, atmospheric circulation data(NCEP)and the sea surface temperature data(SST), the methods of EOF analysis, Yamamoto analysis, MESA analysis, correlation analysis and composition analysis are used to study totaU spatial and temporal distribution characteristics of the rainfall in Spring and respective month over North China, investigate correlation with interannual andinterdecadal variation of sea surface temperature and atmospheric circulation , and analyse mechanism of influence.The total distribution characteristics of the rainfall in spring and respective month over North China: there is interannual variable characteristics of the rainfall * in Spring and respective month, the years of less rainfall are far more than that of more rainfall. There is less difference between the rainfall of the years of less rainfall and average value, whereas there is more difference between the rainfall of the years of more rainfall and average value. There is interdecadal variation of the rainfall in April and May which is more obvious in May. The Rainfall increases from 1962 to 1977 , and decreases from 1978 to 1997 in April ; the Rainfall increasesfrom 1983 to 1992 , and decreases from 1965 to 1982 in May.The results of EOF analysis of the rainfall anomaly in Sping and respective month over North China indicate:Spatial distribution of the first characteristic vecter is consistent in all areas;the second characteristic vecter which is positive (negative) anomaly in north east, and is negative (positive) anomaly in south west in April is east west anomaly in each of Spring., March and May ;the third characteristic vecter is north south anomaly in March. There is the same characteristics of interannual and interdecadal variation between the first characteristic vecter and corresponding percent of the rainfall anomaly ; the second characteristic vecter which is the most obvious in May has interannual variable characteristics in each month.Equatorial Indian Ocean is the most important area which affect interannual variation of the rainfall in Spring, March and May over North China;the second important area is tropic middle-east pacific. When the Indian Ocean SST is positive (negative) anomaly , the rainfall increases (decreases) inSpring, March and May;when tropic middle-east pacific SST is positive (negative) anomaly , the rainfall increases(decreases) in Spring and May. There is significant positive correlation between interannual variation of atmospheric circulation(200 Hpa) in area (25?N-50°N, 110°E-145°E) and that of the rainfall in each month, there issignificant positive correlation between interannual variation of former low level atmospheric circulation and that of the rainfall in Spring and May. There is significant difference between interannual variation of the rainfall in March and that in April and May, the main cause of affecting interannual variation of the rainfall in March possibly is that the energy excitated by SST anomaly in the area which is from equatorial Indian Ocean to Bengal gulf spreads along with big cicular route. The activity of cold air and interannual variation of low level jet are important cause of interannual variation of the rainfall in April. Interannual variation of subtropic high is the main cause of interannual variation of the rainfall in May over North China.There is significant negative correlation between interdecadal variation of the rainfall in April and that of SST in the areas of equatorial Indian Ocean and tropic middle-east pacifi...
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