1991年江淮暴雨与越赤道气流关系初步分析

A PRILIMINARY ANALYSIS ON THE RELATIONSHIP BETWEEN THE CROSS-EQUATORIAL FLOW AND THE HEAVY RAINFALL OVER YANGTZE AND HUAIHE RIVER IN 1991

1991年夏季 ,中国江淮地区发生了大范围的特大暴雨及洪涝灾害 ,造成人民生命财产的巨大损失。文中利用 ECMWF(欧洲中期天气预报中心 )等格点资料及其它常规资料 ,对此次暴雨成因进行了分析。研究结果指出 :1 991年 5～ 7月越赤道气流的特别强劲以及越赤道气流通道位置的异常 ,是造成此次特大暴雨的主要原因之一。同时 ,5月底及 6月初南半球中、高纬度冷空气较早的爆发 ,可能是 1 991年越赤道气流异常的先兆“信号”。

In summer of 1991 heavy rainfall and flood took place over the wide regions of China and made much loss of life and property. The analysis on the cause of this storm rainfall was made with the ECMWF grid wind and other routine data. The results point out that the anomalous strength and the channel’s change of the cross-equatorial flow(CEF)during May to July 1991 are one of the main reasons producing this heavy rainfall.At the sametime,the earlier outbreak of cold air over the middle-high latitude of the Southern Hemisphere may be a“signal”of the 1991’s abnormal CEF.