Absolute Calibration of Sentinel-3A and Jason-3 Altimeters with Sea-Surface and Transponder Techniques in West Crete, Greece

This work presents the latest absolute and relative calibrations for the altimetersof the Sentinel-3A and Jason-3 at the Permanent Facility for AltimeterCalibration in west Crete, Greece. Results have been determined at first with the transponderat the CDN1 Cal/Val site on the mountains of west Crete using the ascendingSentinel-3A Pass No. 14 and the descending Jason-3 Pass No.18. Then, sea-surface calibration has been carried out with the descending Sentinel-3A Pass No. 335 and the ascendingJason-3 Pass No.109 based on the Cal/Val facility on Gavdos island. For Sentinel-3A results have been established for cycles 3–27 using Level 2 (Level 0 for transponder) and Non-Time Critical data. For Jason-3, cycles 5–80 and the S-GDR-D data have been worked with the transpondercalibration, while for the results with sea-surface calibration, cycles 1–80 with the I-GDR-D data have been implemented.