Korean Journal of Remote Sensing (대한원격탐사학회지)

Korean Society of Remote Sensing (대한원격탐사학회)
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Evolution of Internal Waves Near a Turning Point in the South China Sea using SAR Imagery and Numerical Models

  • Kim, Duk-Jin (Remote Sensing Department, Korea Aerospace Research Institute) ;
  • Lyzenga, David R. (Naval Architecture and Marine Engineering, University of Michigan) ;
  • Choi, Woo-Young (Department of Mathematical Sciences, New Jersey Institute of Technology) ;
  • Kim, Youn-Soo (Remote Sensing Department, Korea Aerospace Research Institute)
  • Published : 2007.10.31
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Abstract

Subsurface Internal Waves(IWs) can be detected in satellite images as periodic alternating brighter/darker stripes. It is known that there are two types of IWs-depression type and elevation type-depending on the water depth in stratified oceans. In this study, we have quantitatively verified the process of converting polarity from depression waves to elevation waves using ERS-2 SAR image acquired over the northern South China Sea. We simulated the evolution of IWs near a turning point with a numerical model for internal wave propagation. The simulation results near the turning point clearly showed us not only a conversion process of IWs from depression to elevation waves, but also a similar wave pattern with the observed SAR image. We also simulated SAR intensity variation near the turning point. The upper layer currents were computed at regular intervals using the numerical model, as the IWs were passing through the turning point. Then, an integrated hydrodynamic-electromagnetic model was used for simulating SAR intensity profiles from the upper layer currents. The simulated SAR intensity profiles were compared with the observed SAR intensities.

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