China Water Cover Map (2020/10 m)

The China Water Cover Map (2020/10 m) was developed by the wetland remote sensing research team of Aerospace Information Research Institute, Chinese Academy of Sciences. The map was developed based on an automatic shape-based and inundation frequency-based classification method using time series Sentinel-1 and Sentinel-2 images covering the whole China in the year 2020 with the aid of the remote sensing big data cloud platform. The overall accuracy of CWaC is 85.6% and the kappa coefficient is 0.83. The classification accuracy of rivers, reservoirs, lakes, agricultural ponds, and rice fields all exceed 80%, and the classification accuracy of seasonal wetlands exceeds 70%. At the same time, seven prominent water-related data products are chosen to compare with CWaC. The results show that CWaC has a high degree of consistency with existing data, and its unprecedented spatial resolution shows unique advantages. The CWaC is the first effort on water cover type mapping for the whole China at 10-m spatial resolution, which can provide important information for managing water resources and studying the relationship between the transformation of water cover types and human activities.