After Copernicus Climate Change Service (C3S) took over the AVISO DUACS of the mean sea surface height (MADT) and its anomaly (msla), we now provide version DT2018 where the format changed (netcdf4, new order of variables) and the time series was extended. It includes satellite altimetry data from Topex/Poseidon, Jason-1 & -2 & -3, ERS-1 & -2, Envisat, Cryosat-2, SARAL/Altika, and Sentinel-3a.
We offer the data set "two_sat_merged" which is basically based on data from two satellites throughout the entire period. The data set has daily temporal resolution for msla, madt and the surface current components u & v. On request, we can also provide you with the "all-sat" product, which includes all satellites per time period, but which is also not recommended for long term climatological research.
Details on the data processing can be found in the Documentation section, details on the change in version DT2018 can be found here under the product name SEALEVEL_GLO_PHY_CLIMATE_L4_REP_OBSERVATIONS_008_057.
Last update of data set at ICDC: July 25, 2019