The response of surface chlorophyll to mesoscale eddies generated in the eastern South China Sea
The response of surface chlorophyll to mesoscale eddies generated in the eastern South China Sea
复制标题
南海东部表面叶绿素对中尺度涡的响应
DOI：
10.1007/s10872-020-00540-y
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发表时间：
2020-02-03
影响因子：
2.3
通讯作者：
Xu, Dongfeng
中科院分区：
文献类型：
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作者：
Liu, Jin;Wang, Yuntao;Xu, Dongfeng
利用2003年1月至2016年12月全球涡动数据和叶绿素数据，研究了南海东部中尺度涡在生命周期内对表层叶绿素的响应。结果表明，CHL异常对气旋的响应强于吕宋海峡（LS）和吕宋岛西北近海（NWLI）生成的反气旋。当气旋消失时，CHL异常高于当它们在LS和NWLI中生成时。此外，基于经验正交函数方法，定量分析了不同涡动动力机制（涡动平流、涡动捕获、涡动抽吸和涡动诱导Ekman抽吸）对CHL异常的影响。研究结果表明，在西北太平洋生成的气旋中，CHL异常受涡动抽吸的影响，涡动抽吸的加强作用一直增强到气旋生命周期的中期。在LS产生的气旋CHL异常调制涡平流和线性埃克曼泵。在南海生成的反气旋中，CHL异常是由涡旋捕获、非线性Ekman泵和涡旋泵共同引起的。该研究有助于我们将表层CHL归因于特定的机制，并了解表层CHL对ESCS中产生的中尺度涡旋在其生命周期中的响应差异，从而更深入地了解中尺度涡旋在调节海洋初级生产力中的作用。
This study investigates the response of surface chlorophyll (CHL) to mesoscale eddies generated in the eastern South China Sea (ESCS) during their lifecycles based on global eddy dataset and chlorophyll data from January 2003 to December 2016. The results show that the responses of CHL anomalies to cyclones are stronger than anticyclones generated in the Luzon Strait (LS) and in the area off northwest Luzon Island (NWLI). CHL anomalies are higher when cyclones disappear than when they are generated in the LS and in the NWLI. Furthermore, impacts of different eddy dynamic mechanisms (eddy advection, eddy trapping, eddy pumping and eddy-induced Ekman pumping) on CHL anomalies are quantified during eddy lifecycles based on empirical orthogonal function (EOF) method. Our results reveal that CHL anomalies in cyclones generated in the NWLI are affected by eddy pumping and its strengthening effect enhanced until the middle stage of their lifecycles. CHL anomalies in cyclones generated in the LS are modulated by eddy advection and linear Ekman pumping. CHL anomalies in anticyclones generated in the LS are jointly induced by eddy trapping, nonlinear Ekman pumping and eddy pumping. This study helps us attribute surface CHL to specific mechanisms and understand the differences in the response of surface CHL to mesoscale eddies generated in the ESCS during their lifecycles, and thus gains a deeper understanding of the role of mesoscale eddies in regulating the marine primary production.