How Do Avalanches Form? Grades 6-12
"Consider what factors combine to create this dramatic, destructive force of nature. Join an avalanche forecaster as he completes his daily field observations and evaluates the risk. - There are two basic elements to an avalanche: a steep, snow-covered slope and a trigger that causes a weak layer within the snow pack to collapse. This video segment adapted from NOVA reveals that the shape of the ice crystals of snowflakes within a snow pack is also a critical factor."
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