“ATES gives you five controls you need, not 20,” said Andy Sovick, founder of Beacon Guidebooks, who has been working with onX to incorporate both his guidebook content and the ATES scale into the app. (Sovick has been publishing ski lines with locally evaluated ATES ratings for years.) “We’re baking the cake for you—layering and simplifying things for the user—versus them trying to bake the cake themselves.”

According to Billy Rankin, avalanche educator and ski guide for Irwin Guides in Crested Butte, Colo., the ATES layer will be a powerful tool for backcountry users to be able to instantly see where not to go on any given day. “This makes it so much more black and white when you’re tour-planning with people. Terrain is everything. Assessing the weather—good luck. Snowpack is uncertain. And humans are uncertain trying to make decisions together at the top of the slope. But terrain has the least amount of uncertainty. We can put our hat on it: Terrain’s terrain. It’s always the same, and you really have to rely on it.”

This tool has the capability to help all backcountry users manage risk, but it may have the single greatest advantage to the least experienced—people like the snowshoers who died that day on Hoosier Pass. Seasoned backcountry skiers typically enter avalanche terrain because, well, they like to skis slopes greater than 30 degrees. And these folks will still have to weigh the ATES rating against the snowpack and weather and make their own decisions to go or not go. But for those who have zero desire to enter avalanche terrain, the feature will show them instantly where their tour path should lie. The problem therein might be in how to get the least experienced users—who typically do not use mapping software—educated about the technology. To that end, onX hopes to reach some of these folks by giving free subscriptions to new students enrolled in AIRE level 1 classes.

ATES has been around since the early 2000s, yet onX is the first to incorporate it into digital maps. Until recently, the ratings were limited mostly to manually generated maps and guidebooks like Sovick’s because they were labor- and cost-intensive to assign, making it impossible for platforms like onX to feasibly tackle the project. But in 2020, a grad student by the name of John Sykes developed a program called autoATES, which uses geospatial models to calculate ATES ratings across all digitally mapped terrain.

“No one would be able to figure out if he were hit by a bus,” joked Sovick. “In doing 16 guidebooks, I spent 250 hours rating ATES. And that represents 2 percent of the ski terrain in North America. By myself, I’m never going to get it done. Working with autoATES is so satisfying because I know it’s going to be a lifesaving tool.”

AutoATES starts with satellite-generated beta of slope angle and forest canopy cover, which provides historical records of where avalanches have occurred. That information then allows the program to predict potential release areas and—when crunched with complex calculations involving alpha angles, mass, density, and speed—simulate runouts. It then shows the terrain shaded with the color that corresponds to its ATES rating.

In comparison with ATES maps that were generated manually, autoATES ranks about the same in terms of accuracy, roughly 83 percent. In a concerted and laudable effort to increase accuracy, onX is fact-checking the autoATES ratings, which are public and available for any mapping company to use, with human experts—avalanche forecasters and ski guides—in each area.

“If GAIA wanted to use it, they could do it tomorrow. But the human part is unique to onX,” Sovick said. But, added Joe Risi, senior public relations, events, and partnerships manager at onX, “It’s highly doubtful that other companies are going to do the due diligence of having humans and forecasters to go through the autoATES.”

The legwork required for the human part of the equation is time consuming, to say the least, and onX is rolling out the most popular zones one at a time. To date, the areas where the ATES layer available to users are many parts of Colorado (Crested Butte, Silverton, Loveland Pass) and zones around Salt Lake City and southwest Montana.

“It must be hard for a tech company to say, ‘Slow down and let’s let these ski bums in mountain towns weigh in,’” said Sovick. “But it’s pretty cool that onX is.”