１引言１９９７年５月至１９９８年春季，发生了本世纪以来最强的厄尔尼诺事件．全球许多地区的天气气候出现了显著的异常特征，并诱发了一系列的旱、涝及森林大火等重大灾害，引起了许多国家政府和社会各界的高度关注．厄尔尼诺事件的成因和影响是一个十分复杂的问题，尽管自 1 Introduction From May 1997 to the spring of 1998, the strongest El Niño incident of this century took place. In many parts of the world, weather and climate have shown remarkable anomalies and triggered a series of major disasters such as drought, waterlogging and forest fires, which have aroused great concern of many government and social circles. The causes and effects of the El Niño incident are a very complex issue, albeit from them