摘要
用美国马里兰大学提供的海洋同化(SODA)月平均资料,深入揭示了ENSO模的海洋三维结构及其年际和年代际变率。研究结果指出,ENSO海洋模随深度呈明显规律变化。在热带太平洋,它由热带中东太平洋表层显著海温异常分布型随深度增加逐渐过渡为热带西太平洋次表层显著反号海温异常分布型;在赤道太平洋以赤道西太平洋暖池次表层海温显著异常与赤道中东太平洋表层海温反号显著异常为主要特征。El Nino期间,热带中东太平洋表层为强海温正距平中心,西太平洋暖池次表层为强海温负距平中心,在年际尺度上,160°E以西的西北太平洋副热带海域还存在一个与西太平洋海温异常变化反号、与热带东太平洋同号的区域;La Nina期间正好相反。ENSO循环主要由ENSO年际变率所决定,年际ENSO模具有东部型ENSO事件的海温异常分布特征,其循环是东部型冷暖事件之间的转换,在200m以浅,它具ENSO模相同的三维结构和3-5年的显著年际变化周期;年代际类ENSO模具有中部型ENSO事件的海温异常分布特征,年代际ENSO循环是中部型冷暖事件之间的转换,其影响主要限制在200m以浅的海洋上层,具有ENSO模相似的三维结构和9-23年的显著周期。
Based on the Simple Ocean Data Assimilation （SODA） data set from the University of Maryland, three-dimensional structure of the ENSO mode and its interannual and interdecadal variability are revealed. The results indicate that the ENSO mode changes regularly with depth in the ocean. In the tropical Pacific, the ENSO mode shows a significant sea temperature anomaly （STA） in the central-eastern Pacific （CEP） at surface, and transits gradually with depth to into a pattern of prominent reversal STA in the tropical western Pacific （WP） at subsurface. In the equatorial Pacific, the ENSO mode can be characterized by an out-of-phase distribution of significant STA at subsurface in the warm pool area of the equatorial WP with that at surface of the equatorial CEP During the El Nino events, positive STA center appears at surface in the tropical CEP and negative at subsurface in the WP warm pool, and vice versa during the La Nina Events. It is also indicated that the ENSO cycle is mainly dominated by interannual variations. The interannual ENSO mode has the STA characteristics of eastern pattern ENSO events, whose cycling is the transition of the eastern pattern cold and warm events. It has similar 3-D structure with the ENSO mode, and has significant interannual periods of 3-5a above 200m depths. The interdecadal ENSO-like mode has the STA characteristics of central pattern ENSO events, whose cycling is the transition of the central pattern cold and warm events. Influence of the ENSO-like mode is also mainly restricted to the upper ocean above 200m, and it has similar 3-D structure with the ENSO mode and significant periods of 9-23a.
出处
《海洋与湖沼》
CAS
CSCD
北大核心
2007年第5期385-393,共9页
Oceanologia Et Limnologia Sinica
基金
国家重点基础研究发展计划项目
2006CB403601号
国家自然科学基金项目
40576016
40306006号
中国科学院海洋研究所领域前沿项目
20032111号。
关键词
ENSO模和类ENSO模
海洋三维结构
年际和年代际变率
ENSO mode and ENSO-like mode, Three dimensional ocean structure, Interannual and interdecadal variability
