THE EARTH'S FURIES: Avalanches

Part of the Earth's Furies series: Anywhere on the planet where there is snow, no mountain is spared. Depending on the type of snow, the weather and the slope, an avalanche can reach incredible speeds: more than 300km per hour. A small avalanche can exert the same amount of pressure as a cyclone. Researchers and security experts have set up techniques to detect dangerous areas and limit their impact.

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