Statistical Models and Latest Results in the Determination of the Absolute Bias for the Radar Altimeters of Jason Satellites using the Gavdos Facility

Abstract

The dedicated calibration site for satellite radar altimeters in Gavdos, Greece, has been operational as of 2004. The island of Gavdos is located along a repeating ground track of Jason satellites, adjacent to Envisat, where the altimeter and radiometer do not experience significant land intrusion. In this article, the models and techniques for calculating the satellite altimeter bias, as well as the software tool called “TUCalibrit,” are presented. In summary, over cycles 209–259 for Jason-1 and cycles 1–40 for Jason-2, the altimeter biases have been estimated as B(J1) = +103.6 mm ± 4.7 mm and B(J2) = +181.9 mm ± 6.7 mm, respectively.

Keywords:

• Jason
• altimeter
• calibration
• sea level

Acknowledgements

This work has been supported by the FP7-REGPOT-2008-1, Project No. 229885 (SOFIA), sponsored by the European Commission. Dr. Bruce Haines at the Jet Propulsion Laboratory, NASA (USA); Dr. Pascal Bonnefond at the Geosciences, Observatoire de la Cote d’Azur, France; Dr. Nicolas Picot and Dr. Jean-Damien Desjonqueres from CNES, France, are thanked for their help and support.