What is the difference between the Water Mask layer and the Water Area layer?
The Water Area layer provides estimates of the water area (including permanent ice and water) within each pixel. This layer can be used in conjunction with the Land Area layer to calculate the total surface area of a pixel (the sum of land area and water area).
The Water Mask layer distinguishes between pixels that are completely water and/or ice (Total Water Pixels) and pixels that also contain land (Partial Water Pixels). Pixels labelled as ‘NoData’ in the population count and population density rasters are labelled as ‘Total Water Pixels’ in the Water Mask layer.