| 摘要: |
| 本研究利用Argo温盐、Aquarius遥感盐度等资料，研究了阿拉伯海高盐水入侵孟加拉湾的主要路径及季节变化机制。分析显示阿拉伯海高盐水入侵孟加拉湾存在3种类型，即夏季型、冬季型和春季型。夏季型入侵发生在湾口西部，入侵时间为7—10月，净体积输送达1.53 Sv。冬季型（12月至次年1月）和春季型（3—5月）阿拉伯海高盐水入侵分别发生在湾口中部和东部，净输送量相对较弱，分别为0.39 Sv 和0.41 Sv。夏季西南季风漂流分支的入侵是夏季型阿拉伯海高盐水进入孟加拉湾的主因。秋季赤道Wyrtki急流向东输运并在苏门答腊岛附近海域堆积，使得湾口南部海域海面东高西低，进而产生西向水平压强梯度力，地转平衡关系使得湾口南部高盐水向北入侵孟加拉湾，这一过程是造成冬季型阿拉伯海高盐水入侵孟加拉湾的主要机制。同理，春季Wyrtki急流是引起春季型阿拉伯海高盐水入侵孟加拉湾的主要因素。 |
| 关键词: 海洋水文学 南亚季风 Wyrtki急流 水平压强梯度力 阿拉伯海高盐水 孟加拉湾 |
| DOI：10.3969/J.ISSN.2095-4972.2022.01.013 |
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| 基金项目:国家自然科学基金资助项目（41906013，42130406）；自然资源部第三海洋研究所基本科研业务费专项资助项目（海三科2018030）；亚洲合作资金资助项目（99950410）；全球变化与海气相互作用（二期）专项资助项目（GASI-04-WLHY-01，GASI-04-WLHY-03） |
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| easonal patterns of Arabian Sea high-salinity water intrusion into the Bay of Bengal and its dynamic mechanism |
| TIAN Yongqing,QIU Yun,LIN Xinyu |
| (Third Institute of Oceanography, MNR, Xiamen 361005, China;Laboratory for Regional Oceanography and Numerical Modeling, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China) |
| Abstract: |
| Sea surface salinity from Argo and Aquarius data is used to explore seasonal pathways for Arabian Sea highsalinity water (ASHSW) intrusion into the Bay of Bengal (BOB). The data show that there are three types of, i.e. summer, winter and spring, ASHSW intrusions into the BOB. In summer (i.e. July to October), ASHSW intrudes into the BOB via the western bay mouth with a net volume transport of 1.53 Sv. In winter (December to next January) and spring (March to May), ASHSW intrusions occur in the central and eastern bay mouths with relatively weaker net volume transports of 0.39 Sv and 0.41 Sv, respectively. The intrusion branch of the Southwest Monsoon Current (SMC) is the main factor transporting ASHSW into the BOB in summer. The fall Wyrtki Jet raises the sea level off the coast of Sumatra, resulting in high sea surface high in the eastern bay mouth and a positive (i.e. westward) sea surface high gradient. Then, this westward zonal pressure gradient force drives the northward geostrophic current, which ultimately induces the intrusion of ASHSW into the BOB in winter. The spring Wyrtki Jet is also a major cause for the intrusion of ASHSW during this period under almost the same dynamics in winter. |
| Key words: marine hydrology South Asian monsoon Wyrtki Jet horizontal pressure gradient force Arabian Sea high-salinity water the Bay of Bengal |
