for National Geographic Ultimate Explorer
Ultimate Explorer's Avalanche: Surviving Tragedy airs Sunday, April 18 at 8 p.m. ET/PT on MSNBC TV.
In North America, at least 29 skiers, snowboarders, climbers, snowmobilers, and other backcountry users have died in avalanches this year, falling victim to the same snow that fueled their winter passions.
Powerful and destructive, avalanches are far from random, and understanding avalanches is a science and a skill. Sawtooth National Forest Avalanche Center director Janet Kellam has devoted 25 years to learning how to play safely in the backcountryand to passing that knowledge on to others.
In a recent telephone interview with National Geographic News, Kellam discussed the risks of avalanches and shared some snow know-how.
Are you seeing more avalanche incidents?
Over the past ten years, we've seen a steady increase in winter backcountry use, both motorized and nonmotorized. We've also seen an increase in "human" avalanches and avalanche fatalities. But, while we don't have solid evidence, we feel that the user numbers have increased more than accidents and fatalities.
That is to say, the avalanche education and information available has helped, so that the accident and fatality numbers haven't exploded in the same way that the usage numbers have.
Is it hard to get people to understand the danger?
I think for anybody[beginner] or very experienceduntil you've been around [avalanches] and seen them or been caught in [one] yourself, it's very easy to underestimate these light little snowflakes.
One cubic yard [0.75 cubic meter] of very light powder snowthe size of a big trash can that you'd put out on the curbweighs about 90 pounds [40 kilograms]. That's very light snow.
If you get into snow that's been sitting for a whileheavier powder that's still very skiableone cubic yard weighs 400 pounds [180 kilograms]. The same amount of snow that you could walk onnot even spring snow but just snow that would support youweighs 850 pounds [385 kilograms]. That's an 850-pound garbage can, and that would be [the density of] avalanche debris. I find that very impressive.
So even in a small slide, when you are covered by a couple of cans of snow, well, you are in concrete. And avalanches travel 70 or 80 miles per hour [110 or 130 kilometers per hour], and they accelerate to those speeds very quickly.
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