摘要: |
基于Okubo-Weiss 函数方法对20 年高度计资料进行涡旋识别, 分析了南海中尺度涡的时空分布, 初步研究了中尺度涡旋活动的年际变化特征及其可能的动力机制。结果显示, 南海中尺度涡旋活动具有较为显著的年际变化特征, 通过对涡旋个数、涡区面积、涡动能计算分析表明涡旋活动与ENSO 现象遥相关: 南海中尺度涡活动在El Niño 年较弱, 在La Niña 年较强。可用风场异常解释南海中尺度涡的年际变化与ENSO 现象的负相关关系。El Niño 期间南海年平均意义下的东北风场减弱,风应力旋度绝对值减小, 从而导致了较弱的涡旋活动, 相反La Niña 期间强劲的风场导致了涡旋活动增强。 |
关键词: 南海 中尺度涡 年际变化 ENSO |
DOI:10.11693/hyhz20140900242 |
分类号: |
基金项目:海洋公益性行业科研项目, 201105002-11 号; 教育部科学技术研究项目, 113041A 号; 全球变化与海气相互作用,GASI-03-01-01-05 号。 |
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THE ANALYSIS ON INTERANNUAL VARIATION CHARACTERISTICS OF EDDY ACTIVITIES AND ITS DYNAMIC MECHANISM IN THE SOUTH CHINA SEA |
CUI Feng-Juan1, KUANG Xiao-Di2, WANG Yu1
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1.College of Physical and Environmental Oceanography, Ocean University of China, Qingdao 266100, China;2.National Marine Environmental Forecasting Center, Beijing 100081, China
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Abstract: |
The present study analyses temporal and spatial characteristics of mesoscale eddies in the South China Sea (SCS), identified by the altimeter data with Okubo-Weiss method. In addition, we examine the interannual variation of mesoscale eddies and its dynamic mechanism. Our results show that there is prominent interannual variation of mesoscale eddies in the SCS. And it has a negative correlation with ENSO events suggested by the analysis of number of eddies, total eddy aera and eddy kinetic energy: mesoscale eddy activities are weak (strong) in El Niño (La Niña) years. The wind stress curl decrease (increase) as climatological northeast wind fields weaken (strengthen) inEl Niño (La Niña) years, leading to a weak (strong) eddy activities. |
Key words: South China Sea mesoscale eddy interannual variability ENSO |