 An effective cloud-gap-filled method was developed to fill data gaps in satellite-based remote-sensing observations of snow, cover over High Mountain Asia, resulting in a highly accurate NDSI product with low-range underestimation and acceptable range overestimation errors. This product can provide scientific support for eco-environment sustainable management in the High Mountain region. This article was authored by Gang Dang, Zhiguang Tang, Chin Yu Dong, and others.