Interannual Variability of the Coupled Tropical Pacific Ocean–Atmosphere System Associated with the El Niño–Southern Oscillation
文献类型:期刊论文
作者 | Zhang ronghua![]() |
刊名 | Journal of Climate
![]() |
出版日期 | 1997-06 |
卷号 | 10期号:6页码:1312-1330 |
关键词 | GENERAL-CIRCULATION MODELS HEAT-CONTENT VARIABILITY SEA-SURFACE TEMPERATURE ROSSBY WAVES ENSO GCM SIMULATION RESOLUTION CYCLES WIND |
中文摘要 | Upper-ocean temperature and surface marine meteorological observations are used to examine interannual variability of the coupled tropical Pacific climate system. The basinwide structure and evolution of meteorological and oceanographic fields associated with ENSO events are described using composites, empirical orthogonal functions, and a lagged correlation analysis. The analyses reveal well-defined spatial structures and coherent phase relations among various anomaly fields. There are prominent seesaw patterns and orderly movement of subsurface ocean thermal anomalies. During an El Niño year, positive temperature anomalies occur in the eastern and central tropical Pacific upper ocean. Westerly wind anomalies, displaced well to the west of SST anomalies, occur over the western and central equatorial region. These patterns are accompanied by subsurface negative temperature anomalies in the west, with maxima located at thermocline depths off the equator. A reverse pattern is observed during La Niña. The ENSO evolution is characterized by a very slow propagation of subsurface thermal anomalies around the tropical Pacific basin, showing consistent and coherent oceanic variations in the west and in the east, at subsurface depths and at the sea surface, and on the equator and off the equator of the tropical North Pacific. A common feature associated with the onset of El Niño is an appearance of subsurface thermal anomalies in the western Pacific Ocean, which propagate systematically eastward along the equator. Their arrival to the east results in a reversal of SST anomaly polarity, which then correspondingly produces surface wind anomalies in the west, which in turn produce and intensify the subsurface anomalies off the equator, thus terminating one phase of the Southern Oscillation. At the same time, the continual anomaly movement at depth from east to west off the equator provides a phase transition mechanism back to the west. In due course, opposite anomalies are located in the subsurface equatorial western Pacific, introducing an opposite SO phase and beginning a new cycle. Therefore, the phase transitions at the sea surface in the east and at depth in the west are both caused by these preferential, slowly propagating subsurface temperature anomalies, which are essential to the ENSO evolution. Their cycling time around the tropical Pacific basin may determine the period of the El Niño occurrence. The authors’ data analyses show an important role of the thermocline displacement in producing and phasing SST anomalies in the eastern and central equatorial Pacific. The coherent subsurface anomaly movement and its phase relation with SST and surface winds determine the nature of interannual variability and provide an oscillation mechanism for the tropical Pacific climate system. It appears that interannual variability represents a slowly evolving air–sea coupled mode, rather than individual free oceanic Rossby and Kelvin wave modes. These results provide an observational basis for verifying theoretical studies and model simulations. |
收录类别 | SCI |
语种 | 英语 |
公开日期 | 2014-08-26 |
源URL | [http://ir.qdio.ac.cn/handle/337002/18135] ![]() |
专题 | 海洋研究所_海洋环流与波动重点实验室 |
推荐引用方式 GB/T 7714 | Zhang ronghua. Interannual Variability of the Coupled Tropical Pacific Ocean–Atmosphere System Associated with the El Niño–Southern Oscillation[J]. Journal of Climate,1997,10(6):1312-1330. |
APA | Zhang ronghua.(1997).Interannual Variability of the Coupled Tropical Pacific Ocean–Atmosphere System Associated with the El Niño–Southern Oscillation.Journal of Climate,10(6),1312-1330. |
MLA | Zhang ronghua."Interannual Variability of the Coupled Tropical Pacific Ocean–Atmosphere System Associated with the El Niño–Southern Oscillation".Journal of Climate 10.6(1997):1312-1330. |
入库方式: OAI收割
来源:海洋研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。