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|It takes a PhD in mechanical engineering to look at snow like this. Ed Adams hard at work.|
[Editor's note: This story is part two of a seven-part series on the ski industry's most innovative thinkers and the creative thoughts and ideas that drive the sport forward. If you missed Part I with Tom Wallisch, find it here. Check back next Wednesday for the third installment, a story about two guys who invented an inflatable landing pad for park skiers.]
Part 1: Tom Wallisch
Part 2: Snow ScientistPart 3: Katal Innovations
Part 4: Eric PollardPart 5: Snow forecasterPart 6: Hans SmithPart 7: Rick Greenwald
In 2008, Montana State University professor Ed Adams received a $1.1 million grant from the National Science Foundation (and $600,000 from the M.J. Murdock Charitable Trust) to build a subzero science and engineering facility at MSU, essentially a cold lab to study snow and avalanches. Since then, Adams has written reports with complicated names like "Experimental study of radiation-recrystallized near surface facets in snow." Most of his work helps inform avalanche forecasts for backcountry skiers and for terrain near highways, building developments and ski resorts. We spoke to Ed about surface hoar, avalanche dummies and 'ah ha' moments.
Right now, we're concentrating on how weak layers develop in the snow pack and what environmental conditions create those layers. For instance, if we have a clear day and strong solar input, there's sub-surface heating so we get a recrystallization that'll cause a weak layer to develop. If that layer is buried under another snowstorm, then we have a weak layer sandwiched in between two stronger layers. Which is very dangerous.
Avalanche practitioners refer to this a sweet spot. An ultra weak zone layer. For example, you'll have three people ski a slope and then a fourth person will cut through that sweet spot weak layer and it'll zipper out and trigger the whole slope.
|Testing explosives during morning avalanche control on Bridger Bowl's Ridge.|
The environmental factors? They're all subtle undulations. Air temperature. Wind. Solar radiation. Whether it's clear or cloudy. The topography of the slope. It is the way in which these factors -- and more -- work in combination that determine the snow structure and the avalanche potential.
We have a couple of field sites at the Yellowstone Club, a private ski area in Montana. We set up instruments there and nobody bothers us. Nobody cuts under the ropes there. It's a good place to work. It's not overly busy. We take parameters from the field and try to reproduce them in the lab.
To picture the lab, envision a 10-by-10 room that we can program. We control the temperature of the ceiling, which simulates the sky. There's a solar lamp so we can control the solar radiation. We also control the room temperature and humidity.
Snow scientists always talk about surface hoar. Which is essentially frozen dew. It's a very big weak layer problem.
In the spring, we start collecting boxes of snow and storing it in a cold room so we can look at it through the summer. We harvest snow. We are also able to grow smaller quantities of "fresh snow" in the laboratory.
We try to push the boundaries a little bit at a time. People ask me if we have these 'ah ha' moments. We don't. It's more plodding. We upgrade and move along. We try to look at things in a new way.
We have an avalanche dummy. It's basically a car crash dummy. We take it out to Bridger Bowl when they do control work and we sit the dummy in the middle of a slope. Then we have it get wacked and measure how it handles the crash.
We're looking at the effect of explosives on snow, which haven't been well quantified. It's been experimental. People have always thought, 'If I set a charge here, it'll probably set something off.' We're working at Bridger and Yellowstone Club, putting accelerometers in the snow and microphones in the air and setting off charges to see how the pressure wave from the explosive travels through the snow.
It's hard for me to go skiing and not think about all of this. I was a ski bum for a long time. I first got into this because I was just looking for a way to play in the mountains. Now I look at snow as a material and I look at the properties of it: how does it form, how does it fall apart, how much weight can it handle?
I've never done rocket science. But snow is really difficult to study. It's constantly changing form. It's a shape shifter. Two days later, it's a completely different animal.