印度与东亚夏季风环流对ENSO及其年代际异常响应的数值研究

根据诊断分析结果，利用LAGS改进的L9R15气候谱模式，设计了3个数值试验，讨论了不同的年代际背景下ENSO异常对亚洲夏季风环流的影响。研究表明不同背景的ENSO异常与亚洲夏季风活动存在密切的关系。在冷背景条件下，当ENSO处于发展时，印度夏季风偏弱，风速较小，降水量偏少。而东亚夏季风偏南气流较强，受低气压控制，有利于气流辐合，降水量偏多。在ENSO衰减期，印度夏季风仍偏弱，风速偏小，具有干旱的趋势，而东亚夏季风区大陆仍为低气压控制，风速略有减小，降水量比正常年多，而比ENSO前一年有减少的趋势。在暖背

The Numerical Simulation of the Responding of Indian and East-Asian Summer Monsoon Circulation to ENSO and Interdecadal Variation

Based on L9R15 climatic model. the effect of ENSO events under the differentinterdecadal background on Asian summer monsoon circulation is discussed by three numerical exper-iments. The results show that Asian summer monsoon anomaly cor responding to ENSO events are different under the different interdecadal background. Under the cold background;; the Indiansummermonsoon (ISM) is weak with smaller wind and scaree preicipitation;; and the east Asian summer mon-soon (EASM) is strong with greater northward flow and abundant preicipitation at the increasing stageof ENSO events;; but both of ISM and EASM are weaker at the decreasing stage of ENSO events.Un-der the warm background;; the ISM is weak with small land-sea heating differenee and scarcepreicipitation;; and the EASM is also weak at the increasing stage of ENSO events;; but ISM is muchstronger with the land-sea heating difference;; zonal winds and preicipitation enhancing remarkably;;which is easy to lead to flood over the indian areas. At the same time the EASM is a little stronger thanthat in normal monsoon years.