Abstract. Internal solitary waves (ISWs) are ubiquitous in the Andaman Sea, as revealed by synthetic aperture radar (SAR) images, but their generation mechanisms and corresponding influencing factors remain unknown. Based on a nonhydrostatic two-dimensional model, the generation of ISW packets along a transect of a channel lying between Batti Malv Island and Car Nicobar Island is investigated. Additionally, the influences of topographic characteristics, seasonal stratification variables and tidal forcings are analysed through a series of sensitivity runs. The simulated results indicate that bidirectional rank-ordered ISW packets are generated by the nonlinear steepening of internal tides. An east-west ISW asymmetry is observed, which is attributed to distinct topographic characteristics. The surrounding sills are also capable of generating internal wave beams, which modulate the intensity of ISWs. However, the topographic structure of the west flank of the ridge mainly contributes to the suppression of westward ISWs, which decrease the modulating effect of internal wave beams. During spring tide, the generation of ISWs is enhanced. Under neap tide, ISWs are weak, and the east-west ISW asymmetry is less obvious. Moreover, seasonally varied stratification only has a minor effect on the generation and evolution of ISWs.

中文翻译：

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关于安达曼海内部孤立波的产生和演化

摘要。正如合成孔径雷达（SAR）图像所揭示的那样，内部孤立波（ISW）在安达曼海无处不在，但其产生机理和相应的影响因素仍然未知。基于非静水二维模型，研究了沿巴蒂马尔夫岛和卡尼科巴岛之间通道的断面生成ISW数据包的过程。此外，还通过一系列敏感性分析来分析地形特征，季节分层变量和潮汐强迫的影响。仿真结果表明，双向潮位ISW数据包是由内部潮汐的非线性陡峭产生的。观察到东西方ISW不对称，这归因于独特的地形特征。周围的窗台还能够产生内部光束，从而调节ISW的强度。但是，山脊西侧的地形结构主要有助于抑制西向ISW，从而降低了内部光束的调制效果。在春季潮汐期间，ISW的生成得到增强。在潮汐时，ISW较弱，东西方ISW的不对称性较不明显。此外，季节性变化的分层对ISW的产生和演化影响很小。而东西方ISW的不对称性则不太明显。此外，季节性变化的分层对ISW的产生和演化影响很小。而东西方ISW的不对称性则不太明显。此外，季节性变化的分层对ISW的产生和演化影响很小。