| 摘要: |
| 本研究通过分析布放在南海北部的着陆器流速数据，研究一支蓝移的近惯性振荡信号，发现该信号可以传到600m水深以下，持续时间为11月3-16日。该信号的最大的东向流速为0.133m/s，最大南向流为0.124m/s。谱分析发现垂向流速呈现出5个不同的流核，最强流核发生在600-650m位置。近惯性能量下传速度为67±5m/d，从600m下传到1000m的位置能量耗散18%。经验正交函数（empirical orthogonal function，EOF）分解结果显示，这次近惯性振荡信号开始是第一模态占主导，随后变成高阶模态为主导的形式。由于不知道其信号生成的源头，所以无法确定近惯性振荡形成原因，结合前人的研究结果，可以排除台风引起此次近惯性振荡信号的生成。卫星的海表高度异常显示，此时的正涡度有利于此次近惯性振荡发生蓝移特征。 |
| 关键词: 南海北部 近惯性振荡 谱分析 经验正交函数分解(empirical orthogonal function,EOF) |
| DOI：10.11693/hyhz20190300046 |
| 分类号:P732.3 |
| 基金项目:国家自然科学基金委员会-山东省人民政府联合资助海洋科学研究中心项目，U1406401号；国家自然科学基金委员会-创新研究群体科学基金，41421005号；国家重点研发计划-准实时传输深海剖面锚系观测潜标研发，2017YFC1403400号。 |
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| DEEP NEAR-INERTIAL WAVE IN THE NORTHERN SOUTH CHINA SEA |
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HOU Hua-Qian1,2, YU Fei1, LI Bin3, REN Qiang1, WEI Chuan-Jie1
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1.Institute of Oceanology, Chinese Academy of Science, Qingdao 266071, China;2.University of Chinese Academy of Science, Beijing 100049, China;3.State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016, China
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| Abstract: |
| Based on the ADCP data in the lander located in the northern South China Sea (SCS), a blue shift near-inertial wave signal is studied. The lander was deployed in the northern SCS at 22.10°N/119.28°E in 1135m depth working from July 2017 to January 2018. This near-inertial wave signal transmitted to 600m depth during September 3-16. The maximum meridional velocity was 0.133m/s and the maximum zonal velocity was 0.133m/s. Five different energy cores in the near-inertial frequency band were recognized in spectrum analysis. The maximum energy core was in 600-650m depth. The vertical group velocity was 67±5m/d downward. The energy dissipation was 18% from 600 to 1000m. This near-inertial signal began with the first EOF mode dominant, and then became a combination of higher-order EOF mode dominant. Combined with the results of previous studies, we found that the near-inertial oscillation signal was not caused by a typhoon. As the source of the signal generation was unknown, the cause of the near-inertial oscillation could not be determined. The sea level anomaly data by satellite show that the positive vorticity at that time was conducive to the blue shift of the near-inertial waves. |
| Key words: South China Sea near-inertial wave spectrum analysis empirical orthogonal function (EOF) |
