| 摘要: |
| 本文利用20年的卫星高度计资料，对黑潮延伸体邻近海区（25°—45°N，135°E—175°W）中尺度涡的统计特征以及季节变化进行了统计研究。基于涡旋自动识别方法，共识别出本区域3006个气旋涡轨迹和2887个反气旋涡轨迹，其平均周期分别为9.99周和11.00周，平均半径分别为69.5km和71.8km。长生命周期涡旋的平均半径、涡度、涡动能（EKE）和涡旋能量密度（EI）在生命周期内大致都经历了增大-基本保持不变-减小这三个阶段。绝大多数涡旋沿纬线向西移动，经向移动距离较小，气旋涡和反气旋涡在西向传播过程中都具有明显的向南（赤道）偏离趋势。涡旋的生成数量与总数量均在春夏季达到最多，且这一时期涡旋的平均涡度、EKE、EI处于较高水平。 |
| 关键词: 黑潮延伸体 中尺度涡 统计分析 季节变化 |
| DOI：10.11693/hyhz20170900232 |
| 分类号:P731 |
| 基金项目:国家自然科学基金项目，11102232号；江苏省自然科学基金项目，BK20150711号。 |
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| STATISTICAL CHARACTERISTICS OF MESOSCALE EDDIES NEAR THE KUROSHIO EXTENSION REGION |
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HU Dong1, CHEN Xi2, MAO Ke-Feng2, TENG Jun1, LI Yan2, PENG Xu-Dong1
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1.The 31010 Army of PLA, Beijing 100081, China;2.College of Meteorology and Oceanography, National University of Defense Technology, Nanjing 211101, China
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| Abstract: |
| We analyzed statistical characteristics and seasonal variations of mesoscale eddies in the Kuroshio Extension Region (25°-45°N, 135°E-175°W) based on satellite altimetry data. With the automatic identification method, 3006 cyclonic eddy (CE) trajectories and 2887 anticyclonic eddy (AE) trajectories have been recognized. The mean lifetimes of CE and AE are 9.99 weeks and 11 weeks, and the mean radiuses are 69.5km and 71.8km, respectively. The radius, eddy kinetic energy (EKE), energy intensity (EI), and vorticity of most of the long-lived eddies evolve from increase, linger, to decrease in their lifespans. Most eddies propagate westward while their meridional movement is not significant. Both CE and AE have southward (equatorward) deflection. The amount of newly generated eddies and the total quantity of eddies are larger in spring and summer, during what time, mean vorticity, EKE and EI of CEs are at high levels. |
| Key words: Kuroshio extension mesoscale eddies statistical characteristics seasonal variations |
