Deep-water bathymetric features imaged by spaceborne SAR in the Gulf Stream region



[1] Deep-water (>500 m) oceanic bathymetric features are frequently observed in RADARSAT-1 SAR images in the Gulf Stream (GS) region. They are imaged apparently because of the unique environmental conditions in the region, oceanographically characterized by a strong GS current (2 ms−1) and favorable ocean stratification. SAR image analysis shows the basic characteristics of these bathymetric features. A coincident sea surface temperature image shows that the bathymetric feature is only “visible” by SAR within the GS pathway. The dominant wavelength of the wave-like feature is about 2.3 km and their crests are perpendicular to the GS axis. Shipboard sounding measurements confirm the SAR observation. A theoretical consideration of the ocean current and corrugated bathymetry interaction in a 3-layer ocean is presented. Using representative ocean density profile data and the GS current data, we analyze the requirements for the generation and upward propagation of the disturbance induced by the current-bathymetry interaction.