Link https://daac.ornl.gov/SOILS/guides/IsricGrids.html
GIS raster image files for the following variables: total available water capacity (mm water per 1 m soil depth), soil organic carbon density (kg C/m2 for 0-30cm depth range), soil organic carbon density (kg C/m2 for 0-100cm depth range), soil carbonate carbon density (kg C/m**2 for 0-100cm depth range), soil pH (0-30 cm depth range), and soil pH (30-100 cm depth range).