Kananaskis map navigates risk levels of avalanche terrain

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A new tool is helping outdoor enthusiasts make better decisions when planning trips into avalanche terrain in Kananaskis Country, or to steer clear of avalanche hazards altogether.

The Automated Avalanche Terrain Exposure Scale map, or AutoATES map, uses geospatial modelling to assess avalanche risks based on factors like slope angle, avalanche runout, terrain traps and forest density. The result is an interactive, easy-to-use, computer-generated, topographic map measuring avalanche risk levels from no risk to extreme hazard.

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“One of the biggest issues we see for a lot of new people getting into avalanche terrain — and even experienced people — is terrain recognition. The best way to be able to avoid avalanche terrain, if you’re planning on totally avoiding it and going and doing a hike, is being able to recognize terrain,” said Mike Koppang, a mountain rescue specialist with Kananaskis Mountain Rescue.

“This map gives you another tool in your tool bag to help you be able to identify terrain that’s capable of producing avalanches on that five-step model.”

The map is based on a modified version of the Avalanche Terrain Exposure Scale (ATES), originally developed by Parks Canada staff in the early 2000s. The scale was first created with three terrain classes: simple, challenging and complex. A second version of the scale was introduced in 2023 by its original developer, Parks Canada Banff field unit rescuer Grant Statham, and Cam Campbell of Alpine Solutions Avalanche Services.

The updated version adds two new classes — non-avalanche and extreme terrains.

The automated mapping project is a meeting of the minds of various avalanche experts and agencies across Canada and internationally.

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AutoATES map intended to serve as additional tool in trip planning

John Sykes, an avalanche forecaster with the Chugach National Forest Avalanche Centre in Seward, Alaska and PhD candidate with B.C.’s Simon Fraser University avalanche research program, focuses his studies on decision-making in backcountry skiers by looking at GPS tracks and survey responses. He became involved with the AutoATES map initiative through connections with Avalanche Canada.

“Extreme is a little bit of a unique case,” said Sykes of the ATES scale. “It’s one of the newest classes that came out with ATES version two. Essentially, with that, you’re really looking at terrain where even if you triggered a relatively small avalanche, it could still have high consequences because the terrain is so steep that it would cause you to fall and potentially, even if you weren’t buried in an avalanche, you could get injured.”

The strongest driver in classifying extreme terrain is slope angle, and often, little to no forest cover.

“It’s terrain that people are ice climbing in or doing ski mountaineering where usually it’s a big slope, so if you were to get knocked off your feet climbing or skiing, you would have high consequences just from the terrain itself,” he said.

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Sykes stressed the map does not replace avalanche forecasting or other essential trip planning tools.

“It’s independent of the likelihood of any slope avalanching. It’s just looking at, if there was an avalanche there, what would be the consequences,” he said. “From the forecast, you can get information on the characteristics of the hazard right now and then using the ATES map, you could look at where would be some potentially safe places to go today if we have a really dangerous snowpack.

“Then you might want to pick areas that are more in the simple to challenging range.”

Map shows terrain ranges from ‘simple’ to ‘extreme’

Areas of the map are colour-coded in red for extreme hazard, black for complex, blue for challenging and green for simple. Areas without defined colour have no avalanche terrain risk, according to the scale.

Simple terrain is characterized as having low avalanche exposure or primarily forested geography, with many options to reduce or eliminate exposure to avalanche danger. Challenging terrain is classified as involving exposure to well-defined avalanche paths, start zones or terrain traps like gullies, convexities and slope depressions where options exist to minimize exposure through careful route-finding.

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Neither the forecast nor the map replaces having the ability to evaluate such conditions, as well as changing weather while in the field.

“Looking at the terrain, keeping an eye on conditions as they change throughout the day and making your own knowledge-based decisions is still what’s really, really important. That comes a lot from taking a course and learning how to use the terrain starting with an AST 1 (avalanche skills training) course and considering hiring a guide,” said Koppang.

The AutoATES map is intended to serve as an additional tool to aid outdoor recreationists in trip planning and is to be used in conjunction with reviewing current avalanche forecasts, avalanche skills training (AST) and ensuring anyone that enters avalanche terrain — whether to ski, hike, climb or snowmobile — is equipped with proper safety gear, which includes a beacon, probe and shovel.

Recent avalanches in Kananaskis Country

In light of recent incidents in Kananaskis Country where large skier-triggered avalanches have resulted in fatalities and near misses — events that could potentially have been avoided — the importance of employing resources like the AutoATES map to better grasp avalanche risk grows more apparent.

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On March 10, a size 3 avalanche fully buried two skiers who were riding a line down a lower shoulder of The Tower on a northern slope of the mountain in Spray Valley Provincial Park. Avalanche Canada defines a size 3 avalanche as having the ability to bury and destroy a car, destroy a small building or break a few trees.

The north and northeast aspects of The Tower are shown on the AutoATES map as having primarily extreme avalanche ratings, whereas portions of its south- and west-facing aspects are of lesser risk.

While one of the skiers was able to escape the avalanche, having been buried to the top of his head, the other skier, a 19-year-old man from Kelowna, B.C., was buried much deeper and did not survive.

A short distance away, on March 24, another skier had a close call in a size 3 avalanche on a northwest aspect of Tent Ridge on a feature known as Tent Bowl. The avalanche was triggered by the skier on their fourth turn down the mountain at around 2,400 metres elevation. Photos of the aftermath show the huge, deep persistent slab avalanche slid far and wide down the slope, burying the skier up to their neck.

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Avalanche Canada’s forecast in Kananaskis had the avalanche risk rated as moderate at alpine and treeline at the time, meaning natural avalanches were unlikely but human-triggered slides were possible.

AutoATES map the product of collaboration

Despite the risk being moderate and on the lower scale of the public avalanche danger scale, which ranges from low to extreme, forecasters in the Canadian Rockies have been calling this forecasting season challenging and difficult to predict with freezing levels. Of particular concern is a persistent weak snowpack layer formed in early February.

Sykes said the field of digital mapping is becoming increasingly popular as a tool to use alongside reviewing avalanche forecasts, making it more critical than ever to understand the uses for each.

He stressed, again, how much collaboration has gone into developing the AutoATES map.

Manual ATES maps were created by avalanche experts and then used as benchmarks and measured for accuracy against automated maps. One of the two study areas was for Bow Summit, a popular backcountry recreation area in Banff National Park. The other was for the Connaught Creek area in Glacier National Park in B.C.

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The paper found the overall accuracy of AutoATES compared to ATES benchmark maps for the Bow Summit area was 84.4 per cent compared to manual maps at 84.8 per cent, with variable accuracy across terrain classes. The terrain with the highest rated accuracy for the AutoATES map was simple terrain at 96.6 per cent. The lowest accuracy was for challenging terrain at 59.9 per cent.

The automated map of Kananaskis Country includes only the forecasting area covered by Kananaskis Mountain Rescue forecasters and published on Avalanche Canada.

The map is available for viewing on the Alberta Parks website here.

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