Snow bridge

A 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.

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 centimetres 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]

See also

References

  1. Elaine Freedgood (2000) Victorian Writing about Risk: Imagining a Safe England in a Dangerous World, ISBN 0-521-78108-6 p.193
  2. Berner Oberland Haute Route Journal
  3. "Mountain Operations" (1947) by United States War Department p. 204