Snow Science Aims to Assist Safer Decisions
In seeking to prevent deaths, MSU avalanche researchers find a wide variety of applications
for their studies.
By Kirke Elsass, PhD Student in History, Department of History & Philosophy
July 25, 2019
A shift in focus for avalanche safety
Avalanches threaten recreationists, especially members of the growing community of backcountry enthusiasts.
In 1999, a team of Colorado researchers published a survey that spoke directly to snow and avalanche scientists in the United States.1 Their report, covering 45 years of data, was part congratulations. “A growing understanding of snow science” had informed prevention strategies benefitting miners, highway workers, motorists, and those skiing within ski area boundaries. Avalanche fatalities in those groups had decreased. However, their conclusion read more as challenge than praise. Despite snow science’s help in controlling many environments, total avalanche deaths in the U.S. had increased. Recreationists in uncontrolled avalanche terrain—climbers, backcountry skiers, and snowmobilers—accounted for the rise in avalanche victims. The authors called for assessing “the impact of avalanche safety education” on backcountry recreationists. Could snow scientists continue to advance their physical understanding of snow while investigating the “safety education” problem?
Jordy Hendrikx (center, in red), Associate Professor in Earth Sciences, talks to students. (Photo by Martin Stefan)
To Jordy Hendrikx (Associate Professor of Earth Sciences and Director of the Snow and Avalanche Lab in Earth Sciences at MSU), that merged path of snow science and behavior education is the only option. Studying the behavior of individuals in avalanche terrain complicates what had been the formula for his field: 1 - learn how dangerous slabs develop; 2 - train industry, ski area operators, and highway authorities to recognize and blast apart avalanche threats; 3 - save lives by controlling environments. But studying behavior also raises intriguing questions, fundamental to the field’s orientation and methods: Who can benefit from snow and avalanche science today? And how can snow science be most beneficially developed and applied?
The MSU Snow and Avalanche Lab
You might reasonably assume the shift in avalanche victims—from skiers and laborers in public settings to an adventure-seeking backcountry niche—would narrow the relevance of the Snow and Avalanche Lab. That simply has not been the case. For one, the number of backcountry recreationists has grown while the importance of tourism to Montana’s economy has also risen. The overlap of trends is worth considering. Avalanche deaths always create deep emotional effects for surviving family and friends. But from a land-grant university perspective, Hendrikx considers the economic impact of Montana tourists dying on slopes. He worked with Political Science professors Jerry Johnson and Paul LaChapelle along with MSU Extension to create an avalanche guide for distribution across the state, and he now envisions something similar with the state’s Office of Tourism.
Yet the Lab’s relevance is greater than backcountry enthusiasm alone could support,
thanks to novel connections that Hendrikx makes. He has related mountain snowfields
to settings with similar dimensions of risk, uncertainty, and complexity. Hendrikx
recently delivered the keynote address at a conference of the International Liquids
Terminals Association, whose business in hazardous substances has striking parallels
to professional avalanche accidents. He has also collaborated with Norway-based behavioral
economist Andrea Mannberg on an interdisciplinary project, adding to ongoing work at
MSU with Johnson. Their shared interest lies in how the costs and rewards of decision-making
play out amidst the excitement and perils of snow-covered slopes and how social dynamics
affect such decisions in a group. The ways in which those decisions are compromised,
by mountaintop thrills and by changes in the snowpack across time and space, present
a range of challenges to traditional assumptions about rational choice. Their findings
about decision-making in avalanche terrain may have applications for policy and education
strategies aimed at behavior in a variety of other, off-slope, settings.
Translating science into saving lives
Social scientists and hazard managers who connect with the Snow and Avalanche Lab understand its merged goals of physical and behavioral science. Goal one is to understand the varying and shifting behavior of snow on a mountainside, and how to make informed decisions in such a complicated space. Goal two is to understand and address how group and individual decision-making gets corrupted. The two are inextricable. Treating them as such has not only opened snow science to other fields of research, it also also has the potential to proportionately reduce backcountry avalanche deaths.
“The death rate has actually gone down substantially,” Hendrikx adds, qualifying the rise in U.S. avalanche deaths since 1950. He cites his U.S. Forest Service collaborator Karl Birkeland on this point. Birkeland wrote that from 1995 to 2017 backcountry activity in avalanche terrain increase around eight-fold, an estimate based on sales of avalanche transceivers and hits on avalanche forecast sites. Meanwhile, average annual avalanche deaths held statistically constant.[2]
Avalanche casualties matter to Hendrikx, even as he takes his science beyond their settings. He remains driven to facilitate safety on the slopes, as he simultaneous broadens the scope of the Snow and Avalanche Lab.
More more information on the work that Hendrikx and his fellow researchers are doing, check out The White Heat Project a research collaboration between Hendrikx and researchers from Norway and Sweden.
Avalanche Engineers
Learn more about MSU Snow Science by viewing the video below.
This film documentary was produced by Abby Kent, a recent MFA Graduate in the Department of Film & Photography.
READ THE FULL TRANSCRIPT FOR THE DOCUMENTARY:
(Music playing and snow blowing)
David Walters:
The defining moment can be so small that all it takes is just for someone to jump on the slope and boom, you trigger an avalanche. It’s a really weird feeling when the earth starts to move under your feet.
(Sounds of an avalanche in the Bridger Range near Bozeman, MT)
90% of avalanches are triggered by the victim or someone in the victim’s party. Almost all of them are backcountry recreationists.
Presenting a film by Abby Kent: Avalanche Engineers
David Walters (PhD Candidate in Applied Mechanics, Snow Metamorphism):
I’m an engineer and here in the Sub Zero Lab, I research snow. We recreate avalanches to try to understand how and why they actually work.
The Sub Zero Lab, Montana State University is kept at 18 degrees F.
David Walters:
This lab is really world unique in the fact that we have really good control of the weather in here. We have the ability to simulate the natural weather conditions that can turn this regular beautiful six sided snowflakes into a deadly weak layer.
Tony Lebaron (PhD Candidate in Applied Mechanics, Snow Fracture):
We really just trying to understand the process that causes a slope to fail in an avalanche in the first place. No one really knows what happens at the microstructural level.
When we observe avalanches in the field, we don’t really get any of that in between. In the lab here we can see everything that is happening. From the point that there is not an avalanche, to loading it up, almost a failure, and then after failure. So we really see the whole story.
David Walters:
There is equipment available to us to study the microstructure of snow that is not portable for the field. We can’t lug a 500pound CT scanner out into the field any day.
Tony Lebaron:
The CT scanner offers us the opportunity to see the microstructure of the snow in full glorious three dimensions. So, we can look at every single grain and every single bond that is in the microsctructure. It really allows me to look at what is going to go on during fracture.
This is what snow looks like really up close. This is an image that I pulled out of the CT scanner. So, once I’ve started with this sample, the first thing I need to do is identify the bonds. I’m looking for these necks between the ice crystals, which is where fracture happens in the sample. The bonds are what are actually breaking when an avalanche happens or when snow fractures. So, when I run my model what I am really looking at is how much energy does it take to propagate a fracture across the material. Strong snow tends to be composed of these rounded grains that are very strongly bonded to each other. Weak snow or what we call facets are very sharp very angular grains and the bonds between them are a lot smaller, which means the bonds takes a loss less energy for them to break.
David Walters:
In the lab, we really trying to understand why these types of layers cause avalanches. We’re just trying to recreate everything that we see out in the field. We can recreate a specific day over and over and over again. And we have a beautiful sunny day in here, honestly. Um, so, if I wasn’t doing a snow experiment, I would just throw down a beach chair out and get a tan.
It is really powerful to be able to take a natural experience and pull it into the lab and have complete control over it. We’re going to basically be creating a weak layer in the snow here called radiation recrystallized facets, or sometimes called near-surface facets.
A facet forms when a regular snowflake or maybe a rounded snow crystal is subjected to a very strong temperature gradient. So, with our strong solar radiation that comes into the snow and warms it up subsurface, as well as a cooling affect from the cold clear sky right at the surface, we start to see vapor sublimation. We actually get water vapor that comes off the crystal and it travels along the temperature gradient upwards in the snowpack and when it hits that cold spot, then all that vapor turns back into ice. And twelve hours later, we end up with these drastically different crystals that form a completely new microstructure and behave entirely differently mechanically.
We’ve reached the end of a nice sunny day here, with uh, at least in the lab here, a storm moving in for the night to lay down a new layer of snow that is going to create a pretty dangerous situation for avalanches in this lab tomorrow.
Tony Lebaron (outdoors in the mountains):
I’m at Bridger Bowl, which is a local Montana ski area. We got twenty-three fresh inches of snow and the ski area is kind of crowded, so I’m going to go out of bounds a little bit and see what I can find.
My partner and I are right at the boundary of Bridger Bowl. We’re about to hike up and we’ll be checking out avalanche conditions along the way.
Tony Lebaron: Alright, let’s do a beacon check. (Sounds of beeping).
Woman: Looks like you are good to go.
Tony Lebaron: Alright.
Tony Lebaron:
Studying snow as much as I do, I’m kind of scared by default. I know exactly how weak these layers can be. I know exactly how easy it is to trigger a slab avalanche.
The whole way up I’ve been trying to get data out of the snow. It’s a little less formal data than I might collect in the lab. But, I’ve been jumping on tiny little test slopes to see if there are any instabilities I can find. I’ve been poking in the snow with my ski poles to see if anything feels soft, like a weak layer under the slab. I’m doing an ETC (Extended Column Test) right now, to see how this new powder has bonded to the rest of the snow pack. So, the first thing I’ll do is isolate a column of snow.
Just by tapping here, I got the fracture to go across the entire width of the column. And, what that tells me is that if I were skiing a steep slope, just by putting my weight in one place, I could still propagate a fracture across the entire slope, creating an avalanche.
Avalanche Experiment Day 2: Mechanical Test
(Back in the lab)
David Walters:
So, we had overnight to let a slab layer form over our weak layer. So now I’m just going to be isolating a column underneath our sheer frame. This surface here will be painted – just kind of a random paint pattern, so that the cameras can identify the pattern in the snow and watch how those individual particles are moving in relation to each other.
So, we’ve got two cameras here. They work just like our eyes. They can see in 3-D and these cameras, combined with a really powerful software algorithm, can track that pant pattern and tell us exactly how that snow is moving, to a pretty fine resolution.
But the last thing that we need to do, before an avalanche happens, is to trigger it. Outside that could be a skier, snowmobiler, snowboarder, it doesn’t matter. But in here, we control that with an actuator that we can control the speed and the rate at which we hit that snow pack.
We’ve got everything set up for out mechanical test and we’re all ready to start loading it. So, here we go!
(Soft cracking sound)
And it just broke… it was really quiet, but it just broke. So, in the lab it is pretty anti-climactic, but if we were in the field, this would probably be a pretty large avalanche running down the mountain at this point.
Once we have all of the data, it’s just unmistakable that we’ve seen failure and this corresponds exactly with where our facet layer is.
It’s really key that we can do this test in the lab. We have pretty precise control over everything in here, not just the weather, but our load apparatus. That makes this test very repeatable and we can compare one result to the next and it is not based on human factors and trying to do a test out in the field.
Tony Lebaron (back at Bridger Bowl):
When you are out in the field, you are getting a lot of good feedback on how the snow behaves mechanically, which is really important information if you’re trying to assess avalanche risk. But I think what you miss out there, that is really hard to do in the field, is to look at the microstructure. So, when you are out in the field, I think just pulling out your crystal card and trying to find weak layers is really important.
Sometimes the weak layers can be hard to find. But once you see those facets looking at you from the crystal card, it’s pretty obvious that you are dealing with a weak snowpack.
We have to see every individual grain to understand how a whole mountainside might be working.
Avalanches affect everybody. Mountainous highways are critically affected by avalanches all the time. When a slope avalanches, that effects how quickly that snow is going to melt and enter our watershed. Most people here do some sort of outdoor winter recreation, And, if you do go outdoors in the mountains in winter, then avalanches are going to be a hazard for you. Hopefully we’ll be able to apply my research in ways that can help us save lives.