Assessment of OLCI-A and OLCI-B radiometric data products across European seas

The Ocean and Land Color Instruments (OLCI) operated onboard the Copernicus Sentinel-3 satellites are providing globally distributed Radiometry (OCR) data products of relevance for environmental climate applications. This work summarizes results on assessment fundamental OCR from Operational Baseline 3 Collection OL_L2M.003.01 OLCI-A OLCI-B Sentinel-3A Sentinel-3B, respectively. Evaluated satellite derived normalized water-leaving radiance L WN ( ? ), aerosol optical depth at 865 nm ? a (865) Ångström exponent ? determined in near-infrared spectral region. analyses were performed relying situ reference component Aerosol Robotic Network (AERONET-OC) sites representative diverse water types. comparison with AERONET-OC ) oligotrophic/mesotrophic waters shows cross-mission consistent median percent differences i.e. , biases) varying within ±6% blue-green center-wavelengths. analysis regions characterized by optically complex waters, however, displays systematic negative biases both further increasing dominated chromophoric dissolved organic matter, thus suggesting dependence atmospheric correction type. direct inter-comparison Tandem Phase Sentinel-3B flying 30 s apart same orbit, lower than ±1% 412–560 interval, approximately +5% 620 665 nm, ?7% 400 nm. However, outside indicates large explained notable viewing angle. evaluation across different geographic exhibits overestimated values between +48 + 79% former underestimated ?28% ? 41% latter. A complementary Visible Infrared Imager Radiometer Suite board Suomi National Polar-orbiting Partnership (VIIRS-S), proposed as indirect term data, underestimates respect to various types 410 Nevertheless, opposite products, absolute VIIRS-S do not reveal any or type Overall suggest need developing correction, possibly improving capability identify model scattering processes. • OLCI-A/B Lwn show agreement collection exhibit phase high consistency.