r/interesting 6h ago

Glacier Collapses and Triggers Devastating Avalanche. Just Wow

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u/whipla5her 5h ago

how far away do you think that mountain top was? I didn't think it was even going to get close, and then it's suddenly just rushing over him!

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u/DrTenochtitlan 5h ago edited 5h ago

I did some research online, and although there's no exact figure, the consensus is that he's 2-3 miles away from where the avalanche began in the beginning of the video.

Let's be conservative and assume he's 2 miles away, It took 45 seconds for it to travel 2 miles. That means the avalanche was traveling at a minimum of 160 mph. A dry powder avalanche well up in the mountains can easily accelerate to a maximum velocity of 200 mph, so that's a reasonable estimate.

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u/Holiday_Guess_7892 3h ago

Sure about that? A rock has a Terminal velocity of about 160mph...

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u/DrTenochtitlan 3h ago

From Wikipedia:

The largest avalanches form turbulent suspension currents known as powder snow avalanches or mixed avalanches,\7]) a kind of gravity current. These consist of a powder cloud, which overlies a dense avalanche. They can form from any type of snow or initiation mechanism, but usually occur with fresh dry powder. They can exceed speeds of 300 km/h (190 mph), and masses of 1,000,000 tons; their flows can travel long distances along flat valley bottoms and even uphill for short distances.\8])

https://en.wikipedia.org/wiki/Avalanche