The snow_cci CryoClim FSC products are based on fundamental climate data records (FCDRs) developed by EUMETSAT CM SAF for AVHRR (Karlson et al. 2020) and PMR (Fenning et al. 2017). These have been used to assure having the best possible temporal quality of input data. The FCDRs are based on optical data from AVHRR sensors aboard the satellites NOAA-7, -9, -11, -14, -16, -18, -19, and PMR data from SMMR, SSM/I and SSMIS sensors aboard the Nimbus-7, DMSP F8, DMSP F11, DMSP F13 and DMSP F17 satellites, respectively.

The snow_cci CryoClim FSC processing chain includes retrieval of fractional snow cover per grid cell for all grid cells. Permanent snow and ice areas as well as water bodies are masked in the FSC products using the corresponding classes from the Land Cover CCI map of the year 2000 as auxiliary layers. All FSC products are prepared according to the CCI data standards.

The processing chain was developed by Norwegian Computing Center (Norsk Regnesentral, NR) and Norwegian Meteorological Institute (MET Norway), and the processing took place on the Fram supercomputer operated by UNINETT Sigma2 AS (Sigma2, The Norwegian e-infrastructure for Research & Education).