The S3 4Sci Snow research project is gaining momentum, now with scripts that enable batch processing of two important steps: 1.) collocating OLCI and SLSTR imagery, that is, aligning pixels to a common geographic grid and 2.) converting the imagery to top of the atmosphere reflectance.
(above, 22 August 2016 southern Greenland Sentinel-3 scene of TOA reflectance from OLCI band 21, 1020 nm). In this part of the optical spectrum we find strong reflectance differences between fresh snow cover, melting snow and bare ice (dark areas).
The processing chain the project follows is illustrated below. The collocation happens as OLCI and SLSTR radiances are combined.