High Resolution Snow and Ice Monitoring: Daily cumulative Gap-filled Fractional Snow Cover (raster 60m)

The Copernicus Daily Cumulative Gap-filled Fractional Snow Cover (GFSC) product is generated in near real-time for the entire EEA38 and the United Kingdom, based on radar satellite data from the Sentinel-1 constellation and on optical data from the Sentinel-2 constellation. The product uses Copernicus FSC (Fractional Snow Cover), WDS (Wet/Dry Snow) and SWS (SAR Wet Snow) products along with DEM data as input to form a spatially complete composite of snow conditions, to reduce observational gaps due to clouds and lack of sensor coverage on a daily basis. The product provides the extent of the snow cover per pixel as a percentage (0% – 100%) with a spatial resolution of 60 m x 60 m. The GFSC product is distributed in raster files covering an area of 110 km by 110 km with a pixel size of 60 m by 60 m in UTM/WGS84 projection, which corresponds to the Sentinel-2 input L1C product tile. Each product is composed of four separate GeoTIFF files corresponding to the different layers of the product, and a metadata file. The GF layer provides the gap-filled fractional snow cover, while the QC layers (AT, QCFLAGS, QC) provide information on the quality of the GF layer at the pixel level . The GFSC is one of the products of the pan-European High-Resolution Snow & Ice service (HR-S&I), which are provided at high spatial resolution (20 m x 20 m and 60 m x 60 m), from the Sentinel-2 and Sentinel-1 constellations data from September 1, 2016 onwards. Read more about the GFSC product here: https://land.copernicus.eu/en/products/snow/high-resolution-gap-filled-fractional-snow-cover.哥白尼每日累积间隙填充积雪覆盖率（Gap-filled Fractional Snow Cover，GFSC）产品面向整个欧洲经济区38国（EEA38）与英国实现近实时生成，其数据基础为Sentinel-1星座的雷达卫星数据与Sentinel-2星座的光学遥感数据。该产品以哥白尼积雪覆盖率（Fractional Snow Cover，FSC）、干湿雪（Wet/Dry Snow，WDS）与合成孔径雷达湿雪（SAR Wet Snow，SWS）产品，辅以数字高程模型（DEM）数据作为输入，构建空间完整的积雪状况合成产品，以逐日消除由云层遮挡与传感器覆盖盲区导致的观测数据空白。该产品以百分比（0%–100%）形式提供每个像素的积雪覆盖范围，空间分辨率为60米×60米。 GFSC产品以栅格文件形式分发，单幅栅格覆盖110千米×110千米区域，像素尺寸为60米×60米，采用通用横轴墨卡托（UTM）/世界大地测量系统1984（WGS84）投影，与Sentinel-2输入的L1C产品分幅对应。每个产品包含四个分别对应产品不同图层的独立GeoTIFF文件，以及一个元数据文件。其中GF图层提供间隙填充后的积雪覆盖率数据，而质量控制（QC）图层（包含AT、QCFLAGS、QC字段）则提供像素级别的GF图层质量信息。 GFSC是泛欧洲高分辨率冰雪服务（High-Resolution Snow & Ice Service，HR-S&I）的产品之一，该服务基于2016年9月1日起的Sentinel-1与Sentinel-2星座数据，提供20米×20米及60米×60米两种高空间分辨率的产品。 如需了解更多GFSC产品详情，请访问：https://land.copernicus.eu/en/products/snow/high-resolution-gap-filled-fractional-snow-cover。