Snow detection (snow mask) by VIS/IR radiometry covering full MSG Disk

The main operational characteristics are here highlighted:

• Coverage: MSG SEVIRI Disk
• Cycle: Daily
• Resolution: In SEVIRI the IFOV at the s.s.p. is 4.8 km, that degrades moving away. At average European coordinates becomes ∼ 8 km, and the 3 km sampling rate becomes ∼ 5 km. To simplify matters, we quote as resolution ∆x ∼ 8 km. Sampling is made at 0.05° intervals, i.e. ∼ 5 km, close to the pixel size over Europe.
• Accuracy: To be assessed - Tentative: 20 mm - Depending on geographical situation (flat/forested, mountainous)
• Timeliness: 6 hours
• Formats: HDF5

The basic algorithms for product SE-D-SEVIRI applied in Finland (FMI) and Turkey (METU) are somewhat different. They are recorded independently. The need for two separate algorithms raises from the topographical and vegetational differences. It is well-known that the morphology of snow changes with respect to meteorological factors and topography. Meteorological forcings (i.e., precipitation regime, average air temperature, solar radiation) and local topography (i.e., elevation, slope orientation and mean aspect) are the most explanatory variables affecting spatial and temporal variability and persistence of snow cover.