Glacier coverage data on the Tibetan Plateau in 2013 (TPG2013)

The Tibetan Plateau Glacial Data Product-TPG2013 is a glacial attribute product of the Tibetan Plateau around 2013. It was generated by remote sensing visual interpretation method adopting Landsat8 OLI and HJ 1A/1B multispectral data. The temporal coverage of the data were from 2012 to 2014. 86% of the remote sensing data were obtained in 2013. 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, the elevation attribute data of each glacier were obtained based on the SRTM DEM data, and, finally, the Tibetan Plateau glacial data product-TPG2013 was obtained.青藏高原冰川数据产品TPG2013是2013年左右生成的青藏高原冰川属性数据集。该产品采用陆地卫星8号OLI（Landsat8 OLI）与环境一号卫星1A/1B（HJ 1A/1B）多光谱数据，通过遥感目视解译方法制作完成。该数据的时间覆盖范围为2012年至2014年，其中86%的遥感数据获取于2013年，空间分辨率为30米，覆盖青藏高原全域。鉴于自动遥感提取方法易受云层、阴影及季节性积雪对冰川区域的干扰而产生较大误差，本产品采用人工目视解译作为遥感解译手段。经对比基于专家经验的自动解译与目视解译冰川边界的结果可知，当前基于遥感影像的人工目视解译仍是获取冰川矢量边界的最精准方法。在遥感影像选取环节，主要考量将云层与季节性积雪的影响降至最低，同时兼顾夏季与寒季的影像数据（与中国第二次冰川编目所采用的遥感数据源选取原则有所区别）。同时，针对不同解译人员判别标准存在差异的问题，通过多典型区域对比验证可知，人工目视解译的相对偏差小于4%。基于ArcMap软件平台，对上述遥感影像进行几何校正后，通过目视解译获取最终的冰川矢量边界数据。参照中国第二次冰川编目的格式与要求，完成冰川编码与面积统计工作，并基于航天雷达地形测绘数字高程模型（SRTM DEM）数据提取每一条冰川的高程属性信息，最终得到青藏高原冰川数据产品TPG2013。