AN IMPROVED METHOD FOR MAPPING DEBRIS-COVERED GLACIERS WITH SATELLITE MULTISPECTRAL IMAGE DATA AND DIGITAL ELEVATION MODEL

摘要

Automated glacier mapping from satellite multispectral image data is very difficult because of the similar spectral characters of lateral and terminal moraine with that of neighbor rock. Paul has developed a method which integrate ASTER multispectral image with digital elevation model to map two debris-covered glaciers in Alps. However, there are some problems when using in many mountain glaciers in West of China. The critical slopes which identify the debris-covered tongue from rocks were tested at first, which reveals that there isn't a unique critical slope for all glaciers. Vectors from China Glacier Inventory were used to expand and shrinkage which acting as a mask. A Temperature Index image was calculated by one window algorithm from Landsat band 6 and NDVI. The method combines the advantage of Paul's method with the mask and Temperature Index. Most of the processing can be done automatically. It was applied to Keqikaer debris-covered glacier, west Tianshan Mountain, China.