THE ALASKA SAR DEMONSTRATION: RADARSAT-1 EXPERIENCE AND ENVISAT PLANS

Abstract

Information Service (NESDIS) ENVISAT project is focused on a pre-operational demonstration of wind and vessel position products using, predominately, the Wide-Swath Mode of the ENVISAT Advanced Synthetic Aperture Radar (ASAR). The necessary scientific algorithms, data management techniques, and product production and dissemination procedures are being prototyped using Canadian RADARSAT-1 SAR data. A near real-time demonstration of SAR product production, the Alaska SAR Demonstration (AKDEMO) has been underway since October 1999 for the waters surrounding Alaska. Wind speed, wind vector (with 180 degree ambiguity) and vessel position products are generated within about 6 hours of satellite acquisition and provided to operational agencies for evaluation and validation. Wind validation is accomplished by comparing SAR-derived winds with model output in Alaska and with buoy measurements from the NOAA moored meteorological buoys in the Atlantic off the U.S. East Coast. For validation of vessel positions, fishery observer reports are being paired with SAR-derived positions to ascertain vessel detection success. ENVISAT data will first be taken over the U.S. East Coast buoys to test and validate the wind algorithm. The vessel detection algorithm will be tailored for the ENVISAT ASAR imagery and tested as well. Once the algorithms ar