| 摘要: |
| 基于水下滑翔机在2019年8至10月观测到的温盐资料，本研究分析了西北太平洋混合层总体的变化情况，并探讨了混合层异常变化的原因。结果表明，混合层温度总体上呈现随季节转换逐渐降低的趋势，混合层深度总体上呈现随季节转换逐渐增大的趋势。进一步的相关性分析得出，该海域混合层温度、混合层深度的变化特征主要是由外部大气强迫场（海面风场和净热通量）所决定的。水下滑翔机还观测到了混合层温度异常降低、混合层深度异常变浅的现象。通过计算混合层热收支发现，垂向夹卷作用是海洋混合层内温度降低和混合层深度变浅的主要原因。通过进一步计算研究海域冷涡的上升速度与海水垂向夹卷速度的变化情况，并结合卫星遥感资料，得出海洋的中尺度涡旋活动主导了混合层异常现象的发生。 |
| 关键词: 海洋水文学 水下滑翔机 混合层 中尺度涡 西北太平洋 |
| DOI：10.3969/J.ISSN.2095-4972.2023.01.012 |
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| 基金项目:国家重点研发计划资助项目（2016YFC1402607）；“全球变化与海气相互作用（二期）”专项资助项目( GASI-01-NPAC-STsum) |
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| Characters of mixed layers in the Northwest Pacific based on underwater glider observations |
| YANG Dehou,ZHENG Jianhua,JING Chunsheng,GUO Shaojing,HUANG Jiang,YANG Huayong |
| (Third Institute of Oceanography, MNR, Xiamen 361005, China;Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China;Xiamen Institute of Environmental Science, Xiamen 361021, China;Fujian Provincial Key Laboratory of Marine Physical and Geological Processes, Xiamen 361005, China) |
| Abstract: |
| Based on the thermohaline data observed by an underwater glider in the Northwest Pacific Ocean from August to October 2019, this paper analyzes the variability of the mixed layer and discusses the dynamical mechanism accordingly. The results show that the temperatures of the mixing layer lowered gradually in accordant with the seasonal alternations, but the depth of the mixing layer increasesed. Further correlation analysis shows that the variations of temperature and depth in the mixing layer were mainly determined by the external atmospheric forcing (wind and heat flux). The phenomenon observed by underwater glider showed that the temperature in the mixing layer decreased abnormally and the depth became anomaly shallower. The quantitative analysis of the heat budget within the mixed layer revealed that the vertical enrolling, which caused by the meso-scale eddy and by the temporal variations is the main reason of the phenomenon. It can be concluded that the meso-scale eddy dominated the unusual occurrence of mixed layer. |
| Key words: marine hydrography underwater glider mixing layer meso-scale eddy Northwest Pacific |
