Seasonal Variation of Atmospheric Circulation and the Rainy Years

Based on the observed wind data during 1971—1980, the seasonal variations of the meridional and zonal wind fields in 140oE section are analysed. It is found that in rainy tears during June-July the summer season in the Southern Hemisphere ends 1—2 months earlier than normal in the middle and lower Yangtze River, while the summer season in the Northern Hemisphere starts 1—2 months later than normal. It shows that the flood in the Mei-yu period seems to be associated with the anomalies of the circulations in the Southern and Northern Hemispheres