Glacier coverage data on the Tibetan Plateau in 2001 (TPG2001)

The Tibetan Plateau Glacial Data Product - TPG2001 is a glacial attribute product of the Tibetan Plateau around 2000. It was generated by remote sensing visual interpretation method adopting Landsat5 TM/Landsat7 ETM+ multispectral data. The temporal coverage of the data was from 1999 to 2002. 41% of the remote sensing data were obtained in 2001. They covered the Tibetan Plateau with a spatial resolution of 30 m. Considering the large error of the automatic remote sensing extraction method caused by the impact of clouds, shadows and seasonal snow on glacier areas, the remote sensing inversion method adopted manual visual interpretation. By comparing the results of automatic methods and visual interpretation of glacier boundaries based on experts’ experiences, we know that the manual interpretation based on remote sensing images remains the most accurate method to obtain the glacier vector boundary at present. When selecting remote sensing images, the minimum effects of cloud and seasonal snow were mainly considered. Images of summer and cold season were both selected (different from the principle applied in selecting remote sensing image data source for China's second glacier inventory). At the same time, considering the differences in discriminant standards between different interpreters, the comparison of multiple typical regions showed that the relative deviation of manual visual interpretation was less than 4%. Based on the Arc map software platform, the abovementioned remote sensing images were geometrically corrected, and the final glacier vector boundary data were obtained by visual interpretation. According to the format and requirements of the second glacier inventory in China, the glacier code and area statistics were collected, and the elevation attribute data of each glacier was obtained based on the SRTM DEM data, and finally the Tibetan Plateau glacial data product - TPG2000 was obtained.