东印度洋热带偶极子对声会聚区影响分析  

Influence of tropical dipole in the East Indian Ocean on acoustic convergence region

作　　者：吴双林 李整林 秦继兴[1] 王梦圆[1] 董凡辰 Wu Shuang-Lin;Li Zheng-Lin;Qin Ji-Xing;Wang Meng-Yuan;Dong Fan-Chen(State Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100190,China;School of Ocean Engineering and Technology,Sun Yat-sen University,Zhuhai 519000,China)

机构地区：[1]中国科学院声学研究所,声场声信息国家重点实验室,北京100190 [2]中国科学院大学,北京100190 [3]中山大学海洋工程与技术学院,珠海519000

出　　处：《物理学报》2022年第13期215-226,共12页Acta Physica Sinica

基　　金：国家重点研发计划项目(2018YFC0308600);国家自然科学基金(批准号:11874061,11774374);中国科学院青年创新促进会资助的课题。

摘　　要：大洋中的物理海洋现象影响着水体的变化,从而对其中的声波传播产生重要的影响.首次在东印度洋海域进行的声学调查实验,发现了印度洋热带偶极子物理海洋现象对声传播的影响,利用穿越热带偶极子的声传播实验数据,分析了声源深度和水体起伏对深海会聚区的影响,并对实验中的声传播现象形成机理进行了理论解释.结果表明:东印度洋深海非完全声道环境下,受热带偶极子形成暖水团和声源深度起伏的影响,第2会聚区没有形成,声源深度变深时,更容易形成深海会聚区;印度洋热带偶极子影响下第2会聚区位置处的水体跃层起伏会对下一个会聚区的形成及位置产生重要影响,使得第3会聚区提前形成,会聚区位置向声源方向偏移2—3 km.研究结果对探测及通信声纳在深海复杂环境下应用具有重要指导意义.The physical ocean phenomena in the ocean affect the changes of water body,which has an important influence on the sound propagation.A hyperbolic frequency modulation(HFM)signal sound propagation experiment of towed sound source in the East Indian Ocean(EIO)was conducted in summer 2019.The center frequency of the towed sound source is 300 Hz,and the hydrophone receives the data from 4130 m far.This is the first time that we have conducted the underwater acoustic survey in the Indian Ocean.The influence of the physical ocean phenomenon—Indian Ocean Dipole(IOD)on sound propagation is observed.The experimental data of sound propagation from the IOD are processed and analyzed,the effects of sound source depth and water fluctuation on the deep-sea convergence zone(CZ)are analyzed,and the formation mechanism of sound propagation phenomenon in the experiment is explained theoretically.The results show that the second CZ is not formed under the influence of the warm water mass formed by the IOD and the depth of the sound source in the incomplete deep channel environment of the EIO.Owing to the fluctuation of the sound source depth,the deep-sea CZ disappears at the distance where it should have appeared.When the depth of the sound source becomes deeper,it is easier to form the deep-sea CZ.Under the influence of the IOD,the thermocline fluctuation at the location of the second CZ has an important influence on the formation and location of the third CZ.It is found that the location of the third CZ shifts 2–3 km toward the sound source in the experiment.The research results have important significance in guiding the applications in detection and communication sonar in deep-sea complex environment.

关 键 词：声传播 印度洋热带偶极子 水体起伏 会聚区偏移 

分 类 号：P733.2[天文地球—物理海洋学]