The Relationship Between Tropical Circulation Anomaly And Yangtze River Basin Flooding in 1998 And it's Application in the Prediction

摘要

This paper reviewed the relationship between tropical circulation anomaly and the Yangtze-river basin flooding in 1998. It is indicated that the circulation anomaly patterns of tropical troposphere upper and lower in west pacific provided favorable circulation background for the Yangtze River flooding. In the 1998, the tropical circulation and the convective activities in the west pacific warm pool region were both in the weaker stage of the climate fluctuations, South China Sea summer monsoon were sustainable weak, subtropical summer monsoon were stronger in 1998. These conditions were also favorable to the positive rainfall tendency in the Yangtze-river region. Physical processes how these circulation and underlying surface conditions affect the rainfall tendency were also discussed in this paper. The relationship was applied to prediction.