CryoSat is designed to acquire data continuously while orbiting the planet, switching automatically between its three measurement modes according to a geographic mode mask.

• Low Resolution Mode (LRM) is operated on the continental ice sheet interiors (red), over oceans and over land not covered by other modes
• Synthetic Aperture Radar (SAR) (green) is operated over sea-ice areas and over some ocean basins and coastal zones
• SAR Interferometric (SARIn) (pink) mode is used over steeply sloping ice-sheet margins, small ice caps and areas containing mountain glaciers. It is also used over some geostrophic ocean currents and major hydrological river basins.

The geographical mask is converted into a weekly timeline of instrument commands by the mission planning system, taking into account the CryoSat reference orbit.

The current version of the geographical mode mask v5.0 has been in operation since 01 May 2023. You can download the geographical mask in two different formats:

• .png file (zipped)
• .kml file (zipped)

*Please note that .kml areas in general still suffer from a known problem when containing the geographical poles.

For historic reference, you can also download the previous versions of the geographical mask here:

• Version 4.0 (August 2019)
• Version 3.9 (February 2017)
• Version 3.8 (March 2016)
• Version 3.7 (December 2015)
• Version 3.6 (October 2014)
• Version 3.5 (July 2014)
• Version 3.4 (October 2012)
• Version 3.3 (May 2012)
• Version 3.2 (April 2011)
• Version 3.1 (November 2010)