ABSTRACT
Although internal waves are waves in the interior of the ocean, they leave fingerprints on the ocean surface in the form of roughness variations. These roughness variations can be seen by eye or captured by optical sensors when the light conditions are favorable. However, synthetic aperture radar is the optimal sensor for imaging internal waves from space because it can take images day and night and independent of cloud coverage. Spaceborne SAR images are instrumental in studying the generation, propagation, and dynamics of internal waves. The internal waves visible on SAR images are usually highly nonlinear waves and are often termed internal solitary waves (ISWs), which form wave packets. In this paper we present SAR images of ISWs that were generated (1) by tidal flow over abruptly changing underwater bottom topography (Strait of Gibraltar, Luzon Strait); (2) by trans-critical flow along a shelf (the continental shelf off the Amazon River); and (3) by river and channel plumes (Columbia River in Oregon, USA, and Lombok Strait in Indonesia). Furthermore, we show two examples of interacting ISWs and one example of a mode-2 internal waves.
