近20年来热带印度洋与热带太平洋海气系统相互作用特征的诊断研究

摘要

Based on the data of monthly-mean sea surface temperature (SST), outgoing longwave radiation (OLR) and the 1000 hPa zonal wind velocity from NCEP/NCAR reanalysis data of 1979～1998, the SST anomalies of the tropical Indian Ocean and the Pacific Ocean and the character of correlated circulation have been comprehensively analyzed and studied. It is found that there are interdecadual differences in the intensity of dipole mode, which may represent a characteristic internal mode of the Indian Ocean climate system. In the 1980s, the dipole mode of the Indian Ocean SST is weaker, while in the 1990s it is stronger. There is interactions between the tropical Indian Ocean and the Pacific Ocean systems. In the 1990s, the SST anomaly in the tropical Indian is mainly the response of rnthe Pacific ENSO, while the abnormality of the Pacific ENSO in the 1990s is, to a certain extent, the result of the active Indian Ocean dipole mode. From the angle of observed data diagnosis, the possible cause of the poor prediction skills of ENSO in ZC coupled models of the 1990s has been proposed.%利用1979年1月～1998年12月的月平均海表温度(SST)、向外长波辐射(OLR)和l000hPa纬向风速等NCEP/NCAR再分析资料，对近20年来热带印度洋与太平洋海温异常(SSTA)及相关的环流特征量进行综合分析和研究，发现热带印度洋的内部耦合动力特征模态—偶极子模的强度，存在着年代间的差异，80年代偏弱，90年代偏强。热带印度洋与热带太平洋海气耦合系统之间存在着相互作用，80年代热带印度洋的SSTA主要是对太平洋ENSO的响应，90年代太平洋ENSO的异常发展在一定程度上是受印度洋偶极子模态异常活跃影响的结果。从观测资料诊断分析的角度，找出了90年代后ZC耦合模式对ENSO事件预报失败的可能原因。