Applying SAR interferometric coherence to outline debris-covered glacier

In western China, many glaciers are covered with debris on their terminus or ablation areas. This characteristic makes it difficult to use optical remote sensing data to determine the outlines of glaciers. We present a method to extract the limits of glaciers through the classification of Synthetic Aperture Radar interferometric coherence images. A test site was selected to discuss the efficacy of the present method and classification method based on Maximum Likelihood (ML) was employed. The results were also compared with the outlines of updating Chinese Glacier Inventory (CGI) and validated by field measurements. The conclusions from the study indicate that coherence maps can be used effectively to delineate debris-covered glaciers which could be outlined by optical imagery incorrectly. The main restrictions of this method are some uncertainties from coherence estimation due to different interferometric SAR data employed (i.e., under different weather conditions or surface changed in non-glacier area between two acquisitions).