基于遥感和GIS的我国季风海洋型冰川区冰碛物覆盖型冰川边界的自动识别

Identifying Automatically the Debris-covered Glaciers in China's Monsoonal Temperate-Glacier Regions Based on Remote Sensing and GIS

冰碛物覆盖型冰川边界的自动识别是冰川遥感监测的难点,综合遥感图像和DEM等多种数据,提出了一种基于遥感和地理信息系统的改进的半自动集成分类方法.该方法选择NDSI、NDVI作为分类指标,通过栅格DEM反演地表现象,并利用处于热红外波段的TM6探测地物的热辐射差异,应用栅格图像和GIS进行邻接空间分析,将冰川及冰碛物覆盖型冰川进行区别和分类.选择我国典型的季风海洋型冰川区——贡嘎山地区大量冰碛物覆盖的贡巴冰川作为实例进行研究,取得了较好的分类结果.该方法比Frank Paul提出的方法更适合于我国海洋型冰川的遥感研究,同时也提出了存在的问题.

Monitoring variations of glaciers by remote sensing, especially in China＇s monsoonal temperate-glacier regions, is seriously hampered by debris cover. In this paper a semi-automatic method using remote sensing image and DEM data, based on remote sensing and geographic information system, is suggested. It improves Frank Paul＂ s method by means of choosing NDSI and NDVI indices for discerning glacier and vegetation respectively, utilizing the thermal infrared remote sensing in order to distinguish the area of debris-covered glaciers, combining RS with GIS tightly, acquiring more terrain features with high resolution from grid DEM data, making neighbor-hood and spatial analysis more simply, and integrating fully the classification of glaciers and debris-covered glaciers. The Gongba glacier, a typical debris-covered valley glacier, located in Mt. Gongga, a typical monsoonal temperate-glacier area in China, was selected for such study aiming at evaluating the method. The actual classification result indicates that the method is more acceptable than that developed by Frank Paul in China＇s monsoonal temperate-glacier regions. Finally some problems and expectations on the method are exposed.