Anouk Chamayou (CLS, France); Sylvie Labroue (CLS, France); Giovanni D'Apice (CLS, France); Nicolas Taburet (CLS, France); Julien Renou (CLS, France); Karina Nielsen (DTU, Denmark); Sara Fleury (LEGOS, France); Camille Boulard (LEGOS, France); Fanny Piras (CLS, France); Stefan Hendricks (AWI, Germany); Sebastian Simonsen Bjerregaard (DTU, Denmark); Stine Rose Kildegaard (DTU, Denmark); Pierre Féménias (ESA/ESRIN, Italy); Filomena Catapano (RHEA Group for ESA/ESRIN, Italy)

Sentinel-3 is an Earth observation satellite series developed by the European Space Agency (ESA) as part of the Copernicus Programme. It is designed as a constellation of two identical polar orbiting satellites, for the provision of long-term operational marine and land monitoring services. The constellation currently comprises 2 satellites: Sentinel-3A and Sentinel-3B, launched respectively on 16 February 2016 and 25 April 2018. Among the on-board instruments, the satellites carry a radar altimeter to provide operational topography measurements of the Earth’s surface. Besides measuring the sea surface height, the mission primary objectives also include the measurement of the surface topography over inland waters, sea-ice and land ice.

ESA and the Mission Performance Cluster (MPC) recently developed dedicated delay-Doppler and level-2 processing chains to further improve the performances of the ESA Sentinel-3 altimetry mission. The objective is to provide to the users “Thematic Products” over (1) Inland Waters, (2) Sea-Ice, and (3) Land Ice areas. The first assessments of the Sentinel-3 Thematic Products show that the mission performances are significantly improved in comparison to the previous operational Processing Baseline.

At the time of writing, a full reprocessing of the Sentinel-3 altimetry mission with the Thematic Processors is on-going and almost completed. Thus, the users will have access to a fully homogenous Sentinel-3 altimetry data set over the three thematic land surfaces. These Sentinel-3 reprocessed data are being analysed in detail by the MPC experts. The validation results are summarised in this poster. The quality step-up provided by the new Thematic Products is highlighted, using comparisons to in-situ data, and reference missions such as CryoSat-2 and ICESat-2.

In September 2023 the Thematic Processors will become the ESA’s operational Processing Baseline of the Sentinel-3 altimetry land products. These Thematic Processors will continue evolving independently to better meet the requirements of the Cryosphere and Hydrology user communities.