Pe zăpadă.
The water equivalent of the snow is thickness of the layer of water having the same content. For example, if the snow covering a given area has a water equivalent of 50 cm, then it will melt into a pool of water 50 cm deep covering the same area. This is a much more useful measurement to hydrologists than snow depth, as the density of even freshly fallen snow widely varies. New snow commonly has a density of between 5% and 15% of water. Snow that falls in maritime climates is usually denser than snow that falls in mid-continent locations because of the higher average temperatures over oceans than over land masses. Cloud temperatures and physical processes in the cloud affect the shape of individual snow crystals. Highly branched or dendritic crystals tend to have more space between the arms of ice that form the snow flake and this snow will therefore have a lower density, often referred to as "dry" snow. Conditions that create columnar or platelike crystals will have much less air space within the crystal and will therefore be more dense and feel "wetter".
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2007-07-17 14:29:00