东印度沿岸流的季节变化及其热盐输运  

Seasonal variation of East India Coastal Current and its transports of heat and salt

作　　者：辛红雨 谢强 王卫强[3,4,5] XIN Hongyu;XIE Qiang;WANG Weiqiang(Institude of deep-sea science and engineering,Chinese Academic Science,Sanya 572000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Southern marine science and engineering Guangdong laboratory(Guangzhou),Guangzhou 511458,China;State Key Laboratory of Tropical Oceanography(South China Sea Institute of Oceanology,Chinese Academy of Sciences),Guangzhou 510301,China;Innovation Academy of South China Sea Ecology and Environmental Engineering,Chinese Academy of Sciences,Guangzhou 511458,China;Laboratory for Regional Oceanography and Numerical Modeling,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266061,China;Center for Ocean Mega-Science,Chinese Academy of Sciences,Qingdao 266071,China)

机构地区：[1]中国科学院深海科学与工程研究所,海南三亚572000 [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]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 [5]中国科学院南海生态环境工程创新研究院,广东广州511458 [6]青岛海洋科学与技术国家实验室区域海洋动力学与数值模拟功能实验室,山东青岛266061 [7]中国科学院海洋大科学研究中心,山东青岛266071

出　　处：《热带海洋学报》2022年第2期38-51,共14页Journal of Tropical Oceanography

基　　金：中国科学院战略性先导科技专项(XDA20060502);中国科学院南海生态环境工程创新研究院自主部署项目(ISEE2018PY06);中国科学院重点部署项目(ZDRW-XH-2019-2);国家自然科学基金项目(91958202、41521005);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)。

摘　　要：基于卫星高度计数据、模式数据和同化资料揭示了东印度沿岸流(East India Coastal Current, EICC)年周期上的时空分布特征,并探讨了其可能的影响机制及热盐输运。在年周期上EICC呈现3种分布状态,受季风影响,在东北季风前期(10—12月)和后期(2—5月)为一致的南向(北向)流动;而6—8月EICC呈3段式分布,与另外两个时间段明显不同,表现为9°N以南、16°N以北区域的南向流动和9°—16°N区域的北向流动。前人研究认为印度东海岸的局地风应力是EICC的主要机制,本研究发现除局地风应力外,来自孟加拉湾中部的艾克曼抽吸(EkmanPumping)在全年也发挥着重要作用,并在2—5月(10—12月)驱动EICC的北向(南向)流动,而局地风应力则在10—12月有利于EICC的南向流动。EICC是孟加拉湾低盐水向赤道东印度洋和阿拉伯海输运的一个因素,在海盆间的热盐交换上发挥着重要作用。EICC的热输运在6—12月(2—5月)有利于(不利于)湾内温度的升高;盐输运则在全年都有利于孟加拉湾内盐度的增加。此外,EICC的一致南向(北向)流动以及3段式结构促进了湾内热盐的再分配,对于维持北印度洋的热量和盐度收支平衡具有重要作用。Using satellite altimeter, model and assimilation data, we reveal the spatial and temporal distribution characteristics of the East India Coastal Current(EICC) in the annual cycle, and discuss its possible mechanism, and heat and salt transports.In the annual cycle, the EICC presents three distribution states. Affected by the monsoon, it flows southward(northward) in the early stage(October to December) and late stage(February to May) of the northeast monsoon, while it distributes in three stages from June to August, which is significantly different from the other two periods, showing southward flow in the areas south of 9°N, north of 16°N and northward in the area between 9°N and 16°N. Previous studies suggested that the local wind stress along the east coast of India is the main mechanism of the EICC. In addition to the local wind stress, the Ekman Pumping in the central Bay of Bengal(BOB) plays an important role during the whole year, and drives the northward(southward) flow of the EICC from February to May(October to December), while the local wind stress is conducive to the southward flow of the EICC from October to December. The EICC is a factor for the transport of low-salinity water from the BOB to the Equatorial East Indian Ocean and the Arabian Sea, which plays an important role in the heat and salt exchanges between the basins. The heat transport of the EICC from June to December(February to May) is favorable(unfavorable) to the temperature increase in the BOB;salt transport is conducive to the increase of salinity in the BOB throughout the year. The transport characteristics of the EICC promote the redistributions of heat and salt in the BOB and play an important role in maintaining the heat and salinity budgets in the northern Indian Ocean.

关 键 词：东印度沿岸流 热盐输运 局地风应力 埃克曼抽吸 开尔文波 

分 类 号：P737.14[天文地球—海洋地质]