赤道东印度洋次表层高盐水的年际变化  

Interannual variability of subsurface high salinity water in eastern equatorial Indian Ocean

作　　者：唐娇雨 王卫强[1,3,4] 徐康 张镇秋 TANG Jiaoyu;WANG Weiqiang;XU Kang;ZHANG Zhenqiu(State Key Laboratory of Tropical Oceanography(South China Sea Institute of Oceanology,Chinese Academy of Sciences),Guangzhou 510301,China;University of Chinese Academy of Sciences,Beijing 100049,China;Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou),Guangzhou 511458,China;Innovation Academy of South China Sea Ecology and Environmental Engineering,Chinese Academy of Sciences,Guangzhou 511458,China)

机构地区：[1]热带海洋环境国家重点实验室(中国科学院南海海洋研究所),广东广州510301 [2]中国科学院大学,北京100049 [3]南方海洋科学与工程广东省实验室(广州),广东广州511458 [4]中国科学院南海生态环境工程创新研究院,广东广州511458

出　　处：《热带海洋学报》2023年第1期10-21,共12页Journal of Tropical Oceanography

基　　金：国家自然科学基金(42076020);中国科学院战略性先导科技专项(XDA20060502);中国科学院青年创新促进会人才专项(2020340);中国科学院南海海洋研究所南海新星项目(NHXX2018WL0201);南方海洋科学与工程广东省实验室(广州)人才团队引进重大专项(GML2019ZD0306);热带海洋环境国家重点实验室(中国科学院南海海洋研究所)自主研究项目(LTOZZ2101)。

摘　　要：本文利用2010—2019年东印度洋海洋学综合科学考察基金委共享航次数据、Argo(array for real-time geostrophic oceanography)和简单海洋再分析数据(simple ocean data assimilation,SODA),研究了赤道东印度洋次表层高盐水(subsurface high salinity water,SHSW)的年际变化,并探讨了其形成机制。仅限于春季的观测资料显示,来自阿拉伯海的高盐水位于东印度洋赤道断面次表层70~130m深度处,且具有显著的年际变化。基于月平均SODA资料的研究结果表明,不同时期SHSW盐度异常的变化趋势存在显著差异,2010—2015年趋势比较稳定,而2016—2019年则呈现出显著的上升趋势。通过对SHSW的回归分析表明,风场和次表层纬向流是控制该高盐水年际变化的主要因子。进一步的分析表明,赤道印度洋的东风异常导致水体向西堆积,产生东向压强梯度力,进而激发出次表层异常东向流,最终引起SHSW盐度异常升高。此动力关联在印度洋偶极子事件中尤为显著,这进一步反映了赤道东印度洋SHSW的年际变化受到印度洋偶极子的调制。Based on the data of the comprehensive scientific cruise survey in eastern Indian Ocean from 2010 to 2019,Argo(array for real-time geostrophic oceanography)and SODA(simple ocean data assimilation),the interannual variability of subsurface high salinity water(SHSW)in eastern equatorial Indian Ocean was studied and its formation mechanisms was explored.The observation results limited to spring show that the high salinity water from Arabian Sea is distributed in 70~130m in eastern Indian Ocean equatorial section and exhibits significant interannual variations.And the result based on monthly SODA reveals that the trend of anomalous salinity of SHSW varies significantly in different periods,with a relatively stable trend from 2010 to 2015 and an obvious increasing trend from 2016 to 2019.Wind field and subsurface zonal current are dominant factors that control the interannual variability of the high salinity water by regression analysis of SHSW.Further analysis indicates that the anomalous easterly wind in equatorial Indian Ocean leads to the westward accumulation of water masses,then generates an eastward pressure gradient force,which in turn stimulates the anomalous subsurface eastward flow,and causes the increases of anomalous salinity of SHSW eventually.The dynamical connection is particularly remarkable in Indian Ocean Dipole,which further indicates that the interannual variability of SHSW is modulated by Indian Ocean Dipole.

关 键 词：赤道东印度洋 阿拉伯海高盐水 次表层高盐水 印度洋偶极子 

分 类 号：P731.12[天文地球—海洋科学]