Simulation study on SAR imaging of internal solitary wave polarity conversion process

Abstract

This paper presents a Synthetic Aperture Radar (SAR) imaging simulation method to observe internal solitary waves (ISWs). The method is based on Lynett and Liu's horizontal fully two-dimensional ISW propagation model and a SAR ocean surface imaging model [Lynett, P.J. and Liu, P.L., 2002, A two-dimensional depth-integrated model for internal wave propagation over variable bathymetry. Wave Motion, 36, pp. 221–240]. We simulate ISWs propagating in a variable depth ocean and the resulting internal wave polarity conversion process. Analysis of the simulated SAR images shows the process of ISWs of depression changing to ISWs of elevation. Our conclusion is that the radar signature of ISWs during this process are seriously weakened but do not disappear during the polarity conversion. Comparing our simulation results with a local ERS-2 satellite image, this simulation study also validates the effects of ocean topography on the propagation of internal waves by showing ISW fission and isobath-parallelized propagation direction.