The quality of the Jason-3 significant wave height (SWH) IGDR measurements is estimated over the first twenty cycles. The shape of the joint distribution of the 1 Hz SWH value (mean value over 1 s) and the associated standard deviation (SWH RMS) is analysed. Comparison with other altimeters indicates a good quality of the data, very close to the Jason-2 behaviour.
A second validation step consists in comparing along-track 1 Hz collocated measurements from Jason-3 and Jason-2, during the commissioning phase .
A last test is performed comparing collocated measurements of Jason-3 and other in-flight altimeters: Saral and Cryosat-2.
Comparison results are also given for the Ku-band backscatter coefficient measurements and associated estimated surface wind speed.

Similar analyses will be shown for Sentinel-3, subject to the availability of SRAL data.

A brief validation update for the merge altimeter SWH data base developed at Ifremer (ftp://ftp.ifremer.fr/ifremer/cersat/products/swath/altimeters/waves/) is also given for in-flight missions, together with some insight in the long term backscatter coefficient behaviour for Jason-2 and Cryosat-2.