Coastal Monitoring by Satellite-Based SAR

Abstract

The ability of Synthetic Aperture Radar (SAR) for monitoring surface signatures of swells, wind fronts, bottom features, oil slicks, and eddies has been amply demonstrated. The combined use of IR (AVHRR), ocean color (SeaWiFS, MODIS), and SAR (ERS-1/2, ENVISAT, RADARSAT) data can provide frequent high resolution coverage of the coastal area for the evolution study of oceanic processes. This chapter presents examples of these applications. During the Bering Sea Fisheries-Oceanography Coordinated Investigation (FOCI) field test, simultaneous satellite SAR data and in-situ measurements from moorings and ships were collected. Ships and their wakes are commonly observable in high-resolution satellite SAR imagery. This can be useful in national defense intelligence, shipping traffic, and fishing enforcement, especially when combined with the Vessel Monitoring System (VMS). SAR images can track the movement of the ice edge and floes in the marginal ice zone (MIZ). Results are relevant to climate change and fishery management. Sea-ice motion derived by satellite data can be used to interpret the Arctic ice retreat in the summer of 2007. Underwater bathymetry has been mapped by satellite remote sensing (SAR, SPOT, and LANDSAT) in the Spratly Islands of South China Sea (SCS) for ship navigation. As presented by these case studies, the use of SAR-derived observations can supply valuable information for the protection of the environment.