异常东亚冬季风对赤道西太平洋纬向风异常的影响  

Influence of Anomalous East Asian Winter Monsoon on Zonal Wind Anomalies over the Equatorial Western Pacific

作　　者：普业[1] 裴顺强[1] 李崇银[1] 陈月娟[2] 

机构地区：[1]中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室,北京100029 [2]中国科学技术大学地球与空间科学系,合肥230026

出　　处：《大气科学》2006年第1期69-79,共11页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金资助项目40233033;中国科学院创新项目ZKCX2-SW-210

摘　　要：ENSO由于经常带来大范围的气候异常而倍受关注,赤道西太平洋的纬向风异常对ENSO的发生起着重要作用。首先对赤道西太平洋纬向风异常的发生进行研究,其结果清楚地表明它同东亚冬季风的异常有密切关系。异常强(弱)的东亚冬季风不仅能激发产生赤道西太平洋的西(东)风异常,而且还将在菲律宾以东的西太平洋上导致一个气旋性(反气旋性)环流的形成。研究还表明,上述异常流型产生的物理过程是异常东亚冬季风所造成的气压形势的动力影响,因为在强(弱)东亚冬季风影响下,赤道西太平洋地区会形成向西(东)的气压梯度,即p/x<0(p/x>0)的异常气压形势。通过赤道太平洋的海气相互作用,赤道西太平洋的持续西(东)风异常则将进一步导致El Ni^no(La Ni^na)事件的发生。Zonal wind anomaly over the equatorial western Pacific plays an important role in the occurrence of ENSO. The results of data analysis and theoretical studies show that the strong East Asian winter monsoon （the strong East Asian upper trough activity） will stimulate the anomalous west wind and the strong convective activity （strong intra-seasonal oscillation） over the equatorial western Pacific, and will further stimulate El Nino by air- sea interaction. Based on the NCEP/NCAR reanalysis data （2. 5°× 2. 5° ） for 1958 - 1998 and NOAA OLR data, this paper analyzes the dynamic impact of East Asian winter monsoon on the formation of zonal western （eastern） wind anomalies over the equatorial western Pacific and a cyclonic （an anticyclonic） circulation over the east of Philippines. The physical process that East Asian winter monsoon stimulates zonal wind anomalies over the equatorial western Pacific and ENSO are further discussed. The paper reveals the relationship between zonal western （eastern） wind anomalies over the equator and a cyclonic （an anticyclonic） circulation over the east of Philippines and anomalous strong （weak） the East Asian winter monsoon, especially the formation mechanism of this relationship. The main results are as follows： （1） Both zonal western （eastern） wind anomalies over the equatorial western Pacific and a cyclonic （an anticyclonic） circulation over the east of Philippines, which are closely related to the occurrence of El Nino （La Nina）, are related to strong （weak） East Asian winter monsoon anomalies in the earlier period. Before the occurrence of El Nino （La Nina） event, west （east） wind anomalies occur over the equatorial western Pacific, while a cyclonic （an anticyclonic） circulation occurs over the east of Philippines. However, before these anomalies occur, north （south） wind anomalies, i.e. anomalous strong （weak） East Asian winter monsoon, have already occurred over the northwestern Pacific and the East

关 键 词：异常东亚冬季风 动力作用 赤道太平洋 纬向风 

分 类 号：P461[天文地球—大气科学及气象学]