Find the firn line! The suitability of ERS-1 and ERS-2 SAR data for the analysis of glacier facies on Icelandic icecaps

Icelandic Icecaps are sensitive indicators of climatic fluctuations. Glacie r facies boundaries can be identified using remote sensing techniques; SAR data represents the first real opportunity to monitor glacier facies, witho ut cloud attenuation at regular or inter-annual intervals. This study asses ses the overall suitability of the data for the monitoring of glacier facie s and in particular the firn line altitude (FLA) on Icelandic Icecaps. The results show that the firn line can be identified and located to within +/- 20-40 m (vertically). These results were validated using aerial photograph and ground data. RAIDS (Rapid Information Dissemination System) processed data were found to compare favourably with other satellite data for this ty pe of application.