Internal solitary waves (ISWs), a prevalent hydrodynamic process in the global ocean, play a significant role in oceanic material transport, energy transfer, and marine engineering activities. Based on multi-source Synthetic Aperture Radar (SAR) satellite observations from 2005 to 2022, this study statistically analyzes ISW occurrences in the waters surrounding Hainan Island. The key findings are as follows: The spatial distribution patterns of ISWs in this region are preliminarily revealed. Using continuous timeseries remote sensing imagery combined with insitu measurements, the phase velocities of typical firstmode and secondmode ISWs are calculated. The Korteweg-de Vries (KdV), Benjamin-Ono (BO), and Taylor-Goldstein (T-G) equations are employed to invert these velocities, enabling the selection of suitable propagation models. Results indicate that ISWs near Hainan Island are primarily concentrated in the eastern and southern coastal areas of the island and along the Vietnamese coast, predominantly propagating westward and northwestward, together accounting for 63.7% of all cases. Phase velocities derived from sequential SAR images range from 0.19 to 0.49 m/s. A fieldobserved secondmode ISW exhibited a phase velocity of 0.31 m/s and an upperlayer amplitude of 10.5 m. Case studies further demonstrate that the selection of an appropriate inversion model should not rely solely on the wavelength-to-depth ratio; instead, it requires a comprehensive evaluation incorporating modal characteristics and the evolutionary stage of the waves under local topographic conditions.

A lot of Sentinel-1A/B synthetic aperture radar (SAR) observation taken from South Orkney Islands indicate that its southern plateau can be an oceanic hot spot for internal solitary waves (ISWs). The spatial distribution and physical parameters of these waves are disclosed for the first time. The statistical results show that observed ISWs have two main propagation paths towards south and east off the generation site and that they have an average wavelength of 300 m and crestlength around 80 km. Besides, most observed ISWs are generated before and after local spring tide. The barotropic body force is calculated to identify potential internal tides (ITs) generation locations. It is found that the 1 000 isobaths near 45°W can be an ideal internal tide generation site. We also calculate the generation time for eastward propagating ISWs at ideal internal tide generation site which validates the internal tide release mechanism. It shows the waves are form just to the west of the sill at the time of maximum westward flow and disintegrate into strong ISWs when westward tidal current slackens. Finally, we use the Benjamin-Ono equation in a two-layer mechanism to simulate the characteristic parameters of the studied ISWs. The derived wave amplitude and phase speed are around 9 m and 0.5 m/s respectively, but we lack in situ observation to verify.