Suncups are bowl-shaped open depressions into a snow surface, normally wider than they are deep. They form closely packed, honeycomb, often hexagonal patterns with sharp narrow ridges separating smoothly concave hollows. For a given set of suncups, the hollows are normally all around the same size, meaning that the pattern is quasi-periodic on 20–80 cm scales. [1] [2] The depressions are typically 2–50 cm deep. [3]
Suncups form during the ablation (melting away) of snowy surfaces. It is thought they can form in a number of different ways. These include melting of clean snow by incident solar radiation in bright sunny conditions, [3] but also during melting away of dirty snow under windy or overcast conditions, during which particles in the snow accumulate on the crests between hollows, insulating them. [4]
Suncups are bowl-shaped open depressions into a snow surface, normally wider than they are deep. They form closely packed, honeycomb, often hexagonal patterns with sharp narrow ridges separating smoothly concave hollows. For a given set of suncups, the hollows are normally all around the same size, meaning that the pattern is quasi-periodic on 20–80 cm scales. [1] [2] The depressions are typically 2–50 cm deep. [3]
Suncups form during the ablation (melting away) of snowy surfaces. It is thought they can form in a number of different ways. These include melting of clean snow by incident solar radiation in bright sunny conditions, [3] but also during melting away of dirty snow under windy or overcast conditions, during which particles in the snow accumulate on the crests between hollows, insulating them. [4]