Table 1.

Overview of the various expected changes in snow conditions, affected groups of organisms, processes, or activities and the modelling requirements that are required to predict their occurrence in the near future. The different affected groups, processes, and/or activities have different spatial and temporal extent and resolution; hence models are required to resolve these specific spatial and temporal dimensions

Changes in climate and snow	Affected groups/processes	Modelling requirements to predict these changes	Scale
Temperature variability under the snow (snow insulation)	Soil organisms, dwarf shrubs, cryptogams	Snow depth, snow density, snow type, stratigraphy, and temporal evolution of these through the cold season	0–1 m2
	Ecosystem CO2 fluxes		0–1 m2
	Shrubs and trees		1–10 m2
Ice-layer formation	Humans, sub-Arctic agroecosystems, vegetation, small rodents, reindeer, and species depending on them through direct or indirect trophic interactions	Timing, duration/longevity, compactness, and spread of (ground) ice formation across the landscape, in urban areas, and on transportation infrastructure (roads, airports, culverts)	1–10 m2 and >km2
Avalanche risk	Society, infrastructure, large grazers, and mountainside vegetation, especially trees	Snow stratigraphy/stability through the cold season	100 m2
Snow accumulation	Infrastructure/society, water supply, large grazers and flooding risk	Snow depth, snow water equivalent, timing of heavy snowfall events, and snow (re-)distribution by wind	<100 m2
Snow-cover duration and timing	Agriculture, freshwater ecosystems, terrestrial ecosystems, energy use, northern food security, transportation, and recreation	Snow depth, timing of snow deposition and snowmelt, and resultant sea ice melt out	<100 m2