摘要
According to the rainfall from June to September in India and the East-Asia summer monsoon index at 116°E we select 1971, 1973 and 1975 as the strong years of the summer monsoon over Asia, and 1972, 1976 and 1974 as the weak ones in 1970s. Then, the average Circulation at 500 hPa and 50 hPa of the three strong years (named S year)
