两类ENSO事件非对称性特征分析  

Analysis of the analysis of the asymmetric features for the two types of ENSO

作　　者：李智玉[1,2] 张文君[1,2] 徐海明[1,2] 

机构地区：[1]南京信息工程大学气象灾害教育部重点实验室、气象灾害预报预警与评估协同创新中心,南京210044 [2]南京信息工程大学大气科学学院,南京210044

出　　处：《气象学报》2015年第6期1019-1038,共20页Acta Meteorologica Sinica

基　　金：国家重大科学研究计划项目(2012CB955602);国家自然科学基金项目(41275094、41490643、41575077);江苏高校优势学科建设工程项目(PAPD);江苏省高校“青蓝工程”项目

摘　　要：利用1961—2010年多种海、气观测资料,分析了东部型(EP)和中部型(CP)ENSO事件海温异常的非对称性及可能原因,并讨论了两类ENSO事件的非对称性对大气环流的可能影响。结果表明,海温异常非对称性包括空间分布非对称、强度非对称以及持续性非对称。从动力学角度来看,虽然不同事件发展衰减阶段主导的动力作用不尽相同,但就两类事件强度非对称性而言,海洋垂直对流项起关键性的作用。此外,研究发现,无论是通过海温强迫直接影响的赤道地区或是通过遥相关影响的赤道外地区,大气非对称响应都表现出与海温异常非对称较强的一致性,其中东部型ENSO的非对称性分布与事件暖位相分布相似,而中部型ENSO的非对称性分布与事件冷位相分布相似,且东部型ENSO非对称性差异大于中部型ENSO。The asymmetric features of sea surface temperature（SST）anomalies for eastern Pacific（EP）and central Pacific（CP）ENSO events and their possible mechanisms are analyzed by using a variety of air-sea data during the period of 1961-2010.The responses of the atmospheric circulation to the two types of ENSO are also discussed.The SST anomalies exhibit asymmetry in the spatial distribution,intensity and persistence.Although the dominant mechanisms vary in both the development and decay stages for the two events,the ocean vertical advection term plays a key role in their asymmetry of both EP and CP ENSO events.The local and remote atmospheric responses both show strong asymmetric signal,which is consistent with the asymmetric distribution of SST anomalies.The asymmetric distributions of atmospheric responses in EP-ENSO are similar to those associated with EP-El Ni珘no and the asymmetric responses in CP-ENSO are similar to those associated with CP-La Ni珘na.The intensity of the EP-ENSO related asymmetric responses is much stronger than that of the CP-ENSO.

关 键 词：东部型ENSO 中部型ENSO 海-气耦合特征 非对称性 

分 类 号：P46[天文地球—大气科学及气象学]