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Frm4alt International Review Workshop

“International Review Workshop On Satellite Altimetry Cal/Val Activities and Applications"

23-26 April 2018,
Chania, Crete, Greece.

Workshop url



Transponder calibration

Transponder calibration at the CDN1 ESA Altimeter Calibration Site:

  • CryoSat-2 on 5-Feb-2018 18:41:47 UTC (Previous Cal/Val 5-Jan-2018 at 8:04:26 UTC),
  • Tandem mission of Jason-2 and Jason-3, March-October 2016,
  • Jason-3 continuously every 10 days after its launch,
  • Sentinel-3A every 27 days at 20:00:12 UTC continuously after its launch.


  • Objective 1: Develop and approach, document and demonstrate (by traceability to SI units) how measurements used for satellite altimeter calibration and validation acquired by instruments at the Permanent Altimeter Calibration Facility (PACF) attain Fiducial Reference Measurement status.
  • Objective 2: Design, document and demonstrate procedures to operate the PACF facility for satellite altimeter calibration and validation activities and maintain FRM status.
  • Objective 3: Conduct a full data analysis, derivation and specification of uncertainty budgets, following agreed National Measurement Institute (NMI) protocols, for all measurements made at the PACF facility for satellite altimeter calibration and validation.
  • Objective 4: Document necessary changes at PACF to ensure that the site maintains FRM status.
  • Objective 5: Design, Implement and report altimeter calibration and validation experiments using the PACF site for relevant satellite altimeters (i.e., Jason-2, Jason-3, AltiKa, CryoSat-2, Sentinel-3A and possibly Sentinel-3B).
  • Objective 6: Demonstrate how the PACF activity contributes to the Global multi-technique satellite altimeter calibration and validation approach.


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SeRAC: Sentinel-3 Radar Altimeter Calibration Site in Crete

Serac crete eu


FRM4ALT is continued in the Sentinel-3 Radar Altimeter Calibration in Crete (SeRAC) activity with Operational Support, now in place. The objective of this SeRAC project is to ensure the routine operations and maintenance of the CDN1 transponder Cal/Val site for Sentinel-3A but also for Sentinel-3B Commissioning and Routine Operational Phase. The transponder Cal/Val operations shall be further supported by the sea-surface Cal/val sites established at the Permanent Facility for Altimetry Calibration in west Crete, Greece.

url: www.serac-crete.eu