EM USA Terms and Definitions - FEMA

Avalanche: “The rapid and sudden sliding and flowage of masses of usually incoherent and unsorted mixtures of snow/ice/rock material. (UNDHA, DM Glossary, 1992, p. 20; cites OFDA) Avalanche: Mass of snow and ice falling suddenly down a mountain slope and often taking with it earth, rocks and rubble of every description. (WMO 1992, 66) ................
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