ENSO对其后东亚季风活动影响的GCM模拟研究

NUMERICAL SIMULATION OF THE ENSO INFLUENCES ON EAST-ASIAN MONSOON ACTIVITIES AFTERWARDS

中文关键词:  海表水温距平(SSTA)  ENSO  东亚季风  数值模拟

英文关键词:Sea surface temperature anormaly(SSTA)  ENSO  East-Asian monsoon Numerical simulation

中文摘要:

      将1～3月赤道东太平洋海表水温距平(SSTA)引入大气环流模式,模拟研究了ENSO(厄尔尼诺和拉尼娜)对其后东亚季风活动的影响。结果表明,由于SSTA在大气中强迫激发出了大气低频振荡,使得ENSO对其后的东亚季风活动仍有明显影响。厄尔尼诺之后的夏季,西太平洋副热带高压偏强偏北且西伸明显,中国东部降水偏少,尤其是华北地区;厄尔尼诺之后的冬季,东亚大槽偏深,冬季风偏强。拉尼娜之后的夏季,中国长江下游为异常副热带高压单体控制,江淮流域雨量偏少;拉尼娜之后的冬季,东亚大槽偏弱,东亚冬季风偏弱。厄尔尼诺的影响比拉尼娜的影响略强,两者的影响并非完全反相。

英文摘要:

      Introducing SSTA in the equatorial eastern Pacific into the GCM during January-March,a simulation study about ENSO(EI Nino and La Nina) influences on East-Asian monsoon activities is completed.The results show that the influences of ENSO on the afterward monsoon activities in East Asia are in existance owing to atmospheric low frequency oscillation excited by SSTA.After El Nino event,in the summer,the subtropical high in the western Pacific will be stronger and its location will be to north and west,the precipitatoin is less in Eastern China,particularly in Huabei region;In the winter,the aerotrough in East Asia will be deepening,the winter monsoon will be stronger.After La Nina,in the summer,there is a subtropical high center over the lower reaches of Changjiang River,so that the precipitation is less in ChangJiang-Huai River basin;in the winter,the aerotrough will be weaker,the winter monsoon is weaker.It is also shown that the influence of El Nino is stronger than that of La Nina on the climate and their influences are not the exact opposite.