Files are provided in both NetCDF (.nc) and ASCII Gravsoft (.gri) format, as well as .png images. In ascii gravsoft format the data are stored row‐wise in E‐W rows, from N to S, headed by a two‐line label defining coordinate limits and projection. This format is the simplest possible ASCII grid format. Unknown values are flagged by 9999. The grid label for the CCI data is:‐3350000. ‐650000. ‐650000. 850000. 5000. 5000. (this is N1, N2, E1, E2, dN, DE in meter)‐70 ‐45 (minus reference latitude, central meridian in degrees)The CCI data grid contains a total 541 x 301 points. First data value in file is thus the NW cormer (N = ‐650 km,E = ‐650 km) and last value the SE corner (N = ‐3350 km, E = 850 km). Stereographic projections have by default (0,0) at the North Pole.The data use a Polar stereographic projection, WGS84 ellipsoid, with a reference latitude of 70N, and central meridian of 45W