Sea Level reprocessing – Which version of the product am I currently using ?

From AVISO to Copernicus

For more than 20 years, the multi-satellite Data Unification and Altimeter Combination System (DUACS) has been providing near-real-time (NRT) and delayed-time (DT) altimetry products.

In April 2017, the operational production of some DUACS altimeter sea level products distributed by CNES/AVISO has been taken over by the European Copernicus Marine Environment Monitoring Service (Copernicus Marine Service) with the version DUACS DT2018.

In December 2021 a new version of the products was made available to users : DUACS DT2021 ensemble of products is the most recent release.


More infos :


References Publication

release date of the version

time period covered by the version

funding project

Dibarboure et al., 2011 1993-01-01 -> 2013-08-07 CNES/AVISO


Pujol et al., 2016 April 2014 1993-01-01 -> 2017-05-15 CNES/AVISO


Taburet et al., 2018 April 2017 1993-01-01 -> 2020-06-03 CNES/EUMETSAT/Copernicus Marine Service/C3S
Faugère et al., 2022 December 2021 1993-01-01 -> Today CNES/EUMETSAT/Copernicus Marine Service/C3S


Why do we change the products ? Why do we reprocess ?

  • Change the products to better fit  the user’s needs:
    • Improve the quality of the products
  • Improve the data quality using new standards, more accurate and homogeneous
    • Use of the reprocessed GDR or new standards (new geophysical solutions, new orbits solutions)
    • Use of improved parameters for along-track (L3) and grids (L4) processing
    • Impact expected on both large (global/regional) scales and mesoscales
  • Enlarging the altimetry dataset:
    • Up to 7 missions available simultaneously
    • Collaborative missions not included in DT-2018 (ex: H2B, C2N… )
    • Change of name for H2 & H2G in HY2A – HY2AG

Full altimetric series is reprocessed every ≈ 4 years

The current version of the product correspond to the DT2021 and is available since 14 Decembre on Copernicus Marine Service and 20 October on C3S.

More details of the impact of the version change from DT2018 to DT2021 can be found here.