太平洋次表层海温异常年际变率的信号通道与ENSO循环  

SIGNAL PATHWAY OF INTERANNUAL VARIABILITY OF THE PACIFIC SUBSURFACE OCEAN TEMPERATURE ANOMALIES AND THE ENSO CYCLE

作　　者：陈永利[1,2] 李琦[1,2,3] 赵永平[1,2] 王凡[1,2] 

机构地区：[1]中国科学院海洋研究所,青岛266071 [2]中国科学院海洋环流与波动重点实验室,青岛266071 [3]中国科学院研究生院,北京100049

出　　处：《海洋与湖沼》2010年第5期657-666,共10页Oceanologia Et Limnologia Sinica

基　　金：中国科学院知识创新工程重要方向项目;KZCX2-YW-Q11-02号;国家重点基础研究发展(973)计划项目;2006CB403601号;国家自然科学基金项目;40576016号

摘　　要：利用SODA海洋同化资料,分析了太平洋次表层海温异常(SOTA)年际信号变异特征与ENSO循环的联系。结果表明,热带太平洋的年际变率表现为以160°W为纵轴的东西向和以6°—8°N为横轴的南北向的跷跷板分布,南太平洋和北太平洋中高纬度海洋的SOTA则与热带西太平洋SOTA同号,但强度较弱,这些变化都与ENSO事件密切相关,是ENSO事件的两个主要模态,具57和44个月显著周期。ENSO循环期间,热带西太平洋SOTA强信号中心沿赤道东传,到达赤道东太平洋后加强并北扩,导致ElNi?o或LaNi?a事件,同时从热带西太平洋有较弱SOTA信号向东北和西南传播,在南、北太平洋中高纬度海域产生弱SOTA;同期位于热带东太平洋反号的SOTA强信号中心沿10°—15°N(平均12°N)西传,至热带西太平洋后加强并南扩,为下次LaNi?a或ElNi?o事件准备条件,同时在北太平洋中高纬度海洋还存在着反号弱的SOTA。如此周而复始,完成ENSO循环。太平洋次表层海温年际变化信号除在赤道及以北的热带太平洋存在一个逆时针方向的传播通道外,同时在热带西太平洋有异常信号向南、北太平洋中高纬度海域传播,并指出ENSO循环期间太平洋次表层海温异常年际变率信号传播的可能通道。Based on the simple ocean data assimilation （SODA） dataset, the Pacific subsurface ocean temperature anomaly （SOTA） signal on interannual timescales and its link with the ENSO cycle were analyzed. The results show that the interannual variability in tropical Pacific had special patterns as follows： west-east SOTA seesaw with cross axis at middle Pacific and south-north SOTA seesaw with longitudinal axis along 6°—8°N, with periods of 57 and 44 months. During the ENSO cycle, strong SOTA center in western tropical pacific mainly propagated eastward along the equator. It strengthened and moved northward after it reached the eastern equatorial Pacific, and caused El Ni？o or La Ni？a events. Simultaneously, weak SOTA signal propagated northeast- and southeastward from western tropical Pacific to mid-high latitude areas of north and south Pacific. Meanwhile, strong SOTA center with contrary sign located in eastern tropical Pacific propagated westward along 10°—15°N; it strengthened and move southward after it reaches western tropical Pa- cific and prepares for next La Ni？a or El Ni？o event. At the same time, it isolated and weakened the SOTA in mid-high latitude area of north Pacific. The ENSO cycle will be completed under the repetition of the above processes. Finally, we sketched for the pathway of interannual variability of pacific SOTA to show its relation to ENSO cycle.

关 键 词：太平洋次表层海温异常 温跃层 年际变率信号通道 ENSO循环 

分 类 号：P731.1[天文地球—海洋科学]