3.2 Elevation
We derived elevation information from the ASTER GDEM (Tachikawa et al., 2011), between 44-55°N and 80-94°E (a total of 165 individual tiles with 30 m spatial resolution). The DEM tiles were checked for inconsistencies and artefacts removed using a nearest neighbour approach. The tiles were then re-projected to UTM 45N WGS84, mosaicked to form a single large DEM and resampled to 500 m resolution to be consistent with the resolution of the processed MODIS snow cover product.