1. Landsat Images Download from the websites of the United States Geological Survey (https://www.usgs.gov/) and Geospatial Data Cloud (http://www.gscloud.cn/).
2. Glacier Inventory Acquired from the Second Chinese Glacier Inventory (http://westdc.westgis.ac.cn) and RGI 5.0 (https://www.glims.org/RGI/rgi50_dl.html).
3. SRTM Shuttle Radar Topography Mission digital elevation model with spatial resolution of 1″download from the website http://imagico.de/map/demsearch.php.

1. Pre-processing of Remote Sensing Data： False Colour Compositing of Landsat Image
2. Extracting the preliminary lake extent： Automatically extracted from each image over the entire HMA area using the NDWI based on the near infrared band (NIR) and green band (GREEN) in ArcMap. formula: NDWI=(B_GREEN-B_NIR)/(B_GREEN+B_NIR ) Reference：Mcfeeters, S. K.: The use of the Normalized Difference Water Index (NDWI) in the delineation of open water features, Int. J. Remote Sens., 17(7), 1425-1432, doi: 10.1080/01431169608948714, 1996.
3. Manual Vectorization and Entering of Attribute Data Seven groups were formed to conduct lake boundary vectorization of the 13 HMA sub-regions. After vectorization of a glacial lake, it was required that manual attribute items (e.g., data source and lake type) be input concurrently.
4. Interactive Checking and Accuracy Control (1) Glacial lakes were discerned via human–computer interaction; (2) Glacial lake boundary vectorization results were checked interactively by another vectorization operative; (3) Attribute items such as glacial lake classification, new/disappeared lakes, and separated/coalesced lakes were checked interactively. The Google Earth imagery was used as an important auxiliary reference data source for error examination.

Accuracy of Data： (1) The percentage difference of the absolute area encircled by the manually delineated lake boundary and that derived by the GPS survey varied from 5.5–25.5 %. (2) The average accuracy of the delineation of glacial lake boundaries was within ±0.5 pixels (±15 m). (3) The resulting calculated error indicated that the total absolute area error of HMA glacial lakes was approximately ±231.44 and ±259.68 km2 and the average relative error was ±13.8 and ±13.3 % in 1990 and 2018, respectively.