After the loss of CryoSat, 8 October 2005, Esa has confirmed the CryoSat recovery mission to study Earth’s cryosphere. CryoSat-2 is scheduled to launch in 2009, with CNES’s Doris* precise-positioning system on board.

CryoSat reborn

Designed to meet strong demand from the scientific community, the CryoSat spacecraft was lost last autumn due to a malfunction of its Russian Rockot launcher.

At the latest meeting of its Earth Observation Programme Board, at headquarters in Paris on 23 and 24 February, Esa received the green light from member states to build and launch a CryoSat recovery mission, CryoSat-2. “This decision is very important, as the scientific community in Europe and elsewhere is eagerly awaiting resumption of the CryoSat mission”, said Volker Liebig, Esa Director of Earth observation programmes.

Artist’s impression of CryoSat. Credits: Esa

CryoSat-2 will have the same objectives as the original CryoSat mission; it will monitor the thickness of land and sea ice, and help explain the connection between the melting of polar ice and rising sea levels and how this is contributing to climate change.

Monitoring ice

The CryoSat spacecraft will carry out a 3-year mission dedicated to very precisely monitoring changes in the elevation and thickness of polar ice sheets and floating sea ice. It will orbit at an unusually high inclination, reaching latitudes of 88° North and South.

To accomplish this mission, its payload will include:

  • The SAR/Interferometric Radar Altimeter (Siral), designed to acquire more accurate measurement of land and sea ice surfaces, including irregular sloping edges of land ice. In the past, radar altimeters could deliver data only over the sea and large-scale homogeneous ice surfaces.

  • A laser retroreflector, which will establish the satellite’s precise position, enabling the surface altitude to be determined from the radar signal return time.

  • CNES’s Doris* onboard ranging instrument, able to determine the satellite’s orbit with centimetre accuracy, operating in tandem with a network of ground stations.

For this new mission, CNES is also providing its network of ground orbitography beacons and will be responsible for science data processing.

It will also be tasked with monitoring orbit determination product performance, reprocessing data from Siral and long-term archiving of mission data at its new SALP** altimetry and precise positioning department.

* Doris: Doppler Orbitography and Radiopositioning Integrated by Satellite

** Siral: Service d’Altimétrie et de Localisation Précise