全球500m 分辨率8天无云积雪覆盖数据集（2001-2020）

利用Terra和Aqua两颗卫星的MODIS日值全球500米积雪产品，合成全球8天的500米积雪产品。合成规则是，取8天范围内的最大积雪覆盖。对于合成后有缺失值或云覆盖的区域，利用IMS日值1 km积雪数据进行填补，最终得到8天500米分辨率的无云的积雪覆盖产品。Using the daily 500-meter global snow cover products from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the Terra and Aqua satellites, an 8-day 500-meter global snow cover product was synthesized. The synthesis rule selects the maximum snow cover extent within the 8-day window. For regions with missing values or cloud-covered areas in the synthesized product, gap filling was performed using the daily 1-kilometer snow cover data from the Interactive Multisensor Snow and Ice Mapping System (IMS). Finally, a cloud-free 8-day 500-meter resolution global snow cover product was obtained.