东亚西风异常活动对热带西太平洋西风爆发及ENSO发生的作用

Impacts of Westerly Anomalies over East Asia on Westerly Burst over the Western Tropical and the Occurrence of ENSO Events

本文通过观测资料分析和数值模拟，对８０年代两次ＥＮＳＯ事件产生过程中，东亚西风异常活动对热带西太平洋西风爆发及ＥＮＳＯ发生的作用进行了研究。资料分析结果表明，热带西太平洋低层西风异常的发生，与东亚低层西风异常向南向东传播有关。数值模拟中、东太平洋产生ＥｌＮｉｎ～ｏ现象。相关分析结果表明，东亚西风异常向南传播过程中，欧亚大陆有欧亚遥相关环流形势与之配合，使得赤道西太平洋西风异常猛烈发展，并且随着西风异常东传。

The observation data over the period of 1980～1989 are examined to investigate effects of westerly anomalies over East Asia on westerly burst over the western tropical Pacific and the occurrence of ENSO events by the method of analysis and numerical simulation. The analyzed results show that the westerly anomalies over the western tropical Pacific are caused by the propagation of that from East Asia, which may be connected with teleconnection of EA pattern of the atmospheric circulation anomalies. The numerical simulation results illustrate that the El Nin～o event takes place when the westerly anomalies propagate from the western equatorial Pacific to the central and eastern equatorial Pacific.