Operational use of ERS-1 SAR images in the Canadian ice monitoring programme

ERS-1 SAR images have been used to monitor sea ice in the Canadian east coast and the Gulf of St. Lawrence since December 1992. Operational ice parameters were obtained, in near real-time, through visual image analysis. The information was incorporated in standard daily operational products. Further analysis was conducted later to evaluate the data utility. The images are remarkably useful in discriminating between new ice and water and in delineating ice edges. Structural information of ice surface is usually smeared. Distinction between young ice and first-year ice types, based on backscatter alone, is not reliable. Rules for image interpretation were developed. They are mainly based on structural information in images, ancillary data on weather, and recent and historical ice records. Limitations on data utilization are explained in relation to the sensor and orbit parameters. An insight into operational requirements and their relation to SAR observations is presented.