Glossary
The English version of our glossary is currently under construction and will be regularly updated.
Old snow
Deposited snow; the ice crystals’ original form can no longer be recognised.
Old snow is produced when freshly fallen, loose snow crystals are transformed into larger grains of snow by melting and evaporation processes. When the snow cover increases, the old snow is increasingly compressed and, if it survives the subsequent melting period, ultimately becomes firn. Old-snow formation takes place more quickly at higher temperatures and therefore in more temperate latitudes than it does at extremely low temperatures (e.g. in the polar regions).