Snow bridge

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A snowbridge above a crevasse named Mongo in Antarctica.
A snowbridge above a crevasse named Mongo in Antarctica.
For another meaning, see Avalanche snow bridge

Snow bridge is an arc across a crevasse, a crack in rock, a creek, or some other opening in terrain.[1] It is typically formed by snow drift, which first creates a cornice, which may gradually grow to reach the other side of the opening.

[edit] Dangers

A snow bridge may completely cover the opening and thus presents danger: it creates an illusion of unbroken surface while hiding the opening under a layer of snow of unknown thickness, possibly only several centimeters thick.

Snow bridges may also be formed inside a crevasse making it appear shallow.[2]

Since a snow bridge is thicker and stronger at the edge of a crevasse, a fall through a bridge usually happens at some distance from the crevasse edge. [3]

[edit] See also

[edit] References

  1. ^ Elaine Freedgood (2000) Victorian Writing about Risk: Imagining a Safe England in a Dangerous World, ISBN 0521781086 p.193
  2. ^ Berner Oberland Haute Route Journal
  3. ^ "Mountain Operations" (1947) By United States War Dept p. 204