Copernicus Sentinel-2 and Sentinel-3 Radiometric Performance: Inter-Comparison with LANDSAT8/ 9 and Aqua-MODIS Using Vicarious Methods Over Desert-PICS and DCC Targets

As part of the Copernicus program of the European Commission, the European Space Agency (ESA) developed and operates the Sentinel-2 constellation (S2A, S2B); and in cooperation with the EUMETSAT, they are operating the Sentinel-3 constellation (S3A, S3B). Both are Earth Observation optical missions, where the MultiSpectral Instrument (MSI) is carried on board Sentinel-2 mission and the Ocean and Land Colour Instrument (OLCI) and Sea Land Surface Temperature Radiometer (SLSTR) are on board the Sentinel-3 mission. In the framework of the Copernicus Optical Mission Performance Cluster (OPT-MPC), we use the Database for Imaging Multispectral Instruments and Tools for Radiometric Inter-comparison (DIMITRI) to perform the radiometry intercomparison of the Level-1 products. The aims of this presentation are:

1) to assess the quality of the user products;

2) to monitor the temporal evolution of the radiometry of the instruments MSI, OLCI and SLSTR for both units A and B and;

3) to perform radiometric intercomparison with similar optical missions such as Landsat-8, Landsat-9 and Aqua-MODIS.

The results of the intercomparison show a good stability of the sensors, although SLSTR-A & B show slight positive trends. MSI, OLI and SLSTR pairs show good agreement better than 1% while OLCI-A is brighter than OLCI-B up to 2-3% over the VNIR spectral range. The results show a good agreement between MSI/OLI to better than 1% except band B01 (443 nm) over VNIR bands.

Furthermore, a radiometric validation has been performed using Deep Convective Clouds (DCC) method. All level 1 products from satellites Sentinel-2A, Sentinel-2B, Landsat-8 and Landsat-9 within ±20° of latitude are monitored and monthly radiometric statistics are computed over the detected DCCs. The DCC results are consistent with the PICS method ones over the VNIR spectral range.