CryoSat-2 skal måle tykkelsen på is
CryoSat can distinguish between altimetry signals returned from sea ice and open water - the difference between the two is known as the 'freeboard', and can be used to derive ice thickness.
Over topographic surfaces, the first radar echo comes from the nearest point to the satellite. CryoSat can measure the angle from which this echo originates, so that the source point can be located on the ground. This, in turn, allows the height of that point to be determined.