Climate Change is Dangerously Shifting Avalanche Patterns

Rising temperatures in the Alps are transforming snow stability, making wet-snow avalanches a growing threat for mountain communities and adventurers.

My husband and I met through rock climbing, ice climbing, and mountaineering, something that makes for very interesting “how you two met stories.”

Indeed, mountains have always been our happy place, both before and after we met. And once together as a team, we made sure we had as many outdoor dates as we could. We knew that things wouldn’t be so easy if we ever had kids (spoiler, they weren’t).

However, our agendas didn’t always allow us to get out and about together, and we had to rely on other partners from time to time.

A few years ago our local climbing club organized an ice-climbing trip to the Adirondacks. We’ve been there a handful of times, and we love all the possibilities the landscape has to offer there. Unfortunately, I had a conference to attend that weekend, but I told hubs that he should go regardless.

Once there, he partnered up with this recently graduated lady who ended up being the party’s soul. She dreamed of becoming a professional mountaineer and spending a year between college and grad school climbing at high altitudes. She climbed every route multiple times, and by the end of the trip, she was knowledgeable and strong for her big trip.

A couple of years later, I saw something that caught my attention. We follow most climbing magazines, and they often mention people who have passed away in unfortunate accidents. There was a photo of a young lady, and she looked familiar.

Was she hubs’s friend? I had only seen her in photos.

When I showed him the picture, he broke up in tears. It was her, gone at 22 years old. She had partnered with a very experienced climber and accomplished many first ascends, but an unexpected avalanche had the last word. Our community was devastated.

The truth is that, in recent years, more and more mountain climbers have been taken by unexpected avalanches. But why? Well, today’s story has something to say about it. today’s story has something to say about it.

If you’ve ever stood atop a snowy mountain, you know that snow avalanches aren’t just another part of the landscape—they’re a powerful force that commands both respect and caution. If you are into any winter sports, you treat them with a lot more than respect: you fear them as much as you admire them.

A new study by Dr. Stephanie Mayer and her team at the Swiss Federal Institute for Forest, Snow, and Landscape Research (WSL) dives into what climate change means for snow avalanches in the Swiss Alps. And while we might expect fewer avalanches due to decreasing snow, the reality is a bit more complex.

In fact, by the end of this century, Swiss mountain ranges may see more of a certain type of avalanche: wet-snow avalanches. So, how does this shift affect the Alps, and what does it mean for those who live, work, and play there? What does it mean for mountaineers worldwide?

The study looked at avalanche data from seven sites across Switzerland’s Alpine region, including the Weissfluhjoch above Davos and a location near Zermatt, both high-altitude spots. Dr. Mayer and her team used computer models to simulate how avalanches respond to various climate scenarios.

They specifically examined two types of avalanches: dry-snow avalanches, which are common in colder conditions, and wet-snow avalanches, which occur when snow absorbs meltwater or rain. For their projections, they factored in three climate scenarios, ranging from mild to severe warming. These simulations helped them understand how the balance between dry and wet avalanches might change.

In my experience, these simulations can be very powerful at predicting certain major events. But what did the authors find?

In short, the results suggest that while dry-snow avalanches could become less common as temperatures rise, wet-snow avalanches are expected to increase significantly, particularly at elevations above the treeline (about 1,800 meters and up).

According to Dr. Mayer, “The number of dry avalanches will decrease, but above the tree line, the increase in wet snow avalanches will partially offset this decrease.” So, despite shrinking snowpacks, avalanches aren’t going anywhere—they’re just changing their form.

But why is this changing?

This change is rooted in the way warmer weather impacts snow. As Dr. Mayer explains, “Less snow does not mean fewer avalanches.” In dry-snow avalanches, which are often triggered by new snowfall, the snow layers are typically colder and dry, creating weak points that cause large slides.

But with warming, there’s less cold snowfall at lower elevations, so fewer dry avalanches occur. Instead, warmer conditions lead to more frequent wet-snow avalanches, which happen when meltwater or rain seeps into the snowpack, creating a heavier, wetter mass that can slip with less warning. Yes, as if avalanches weren’t scary enough yet.

And what are the implications of this?

For ski resorts, avalanche safety services, and winter sports enthusiasts like us, this trend brings both new risks and challenges. For one, wet-snow avalanches are notoriously tricky to manage. Unlike dry avalanches, they can’t be easily triggered by controlled explosions or other preventive measures, a common tactic used to keep slopes safe.

“The only safety measure that helps is to close endangered areas of a ski resort,” Dr. Mayer explains. This measure may become necessary more often, especially during peak tourist seasons when wet avalanches are likely to be on the rise. I can picture many sad tourists in the horizon.

However, as you can imagine, the implications of Mayer’s research extend beyond Switzerland. While the study focuses on specific Swiss sites, its findings are relevant for similar mountainous regions, including Canada’s Columbia Mountains, where climate patterns mirror those in the Alps.

In these regions, increasing temperatures will likely lead to a higher snow line, reducing the overall snow depth but potentially concentrating avalanche activity at higher altitudes.

According to Dr. Mayer, this could mean that avalanches reach valley locations less often, which is good news for lower-elevation communities. However, the study warns that extreme snowfall events won’t disappear entirely. When they do happen, high-altitude avalanches could still gather enough force to make it down to lower valleys, especially if channeled by specific terrain features like rocky corridors.

This research suggests that safety authorities may need to review their current hazard maps, which outline areas at risk of avalanches.

“The responsible authorities [should] review their hazard maps and, if necessary, adapt them to the changing hazard situation,” Dr. Mayer advises. Updated maps could help communities prepare for the evolving risks posed by warming, especially as new climate models offer more precise insights into future extreme snow events.

Looking ahead, Dr. Mayer’s study encourages Alpine communities, resorts, and avalanche safety teams to stay proactive. Climate change isn’t just reducing snow cover; it’s shifting how snow behaves in the mountains.

As wet-snow avalanches become more frequent, effective safety measures and public awareness will play an even greater role in keeping mountain areas safe. This study offers a valuable forecast of what lies ahead, helping us understand that in a warming world, avalanches will continue to shape the winter landscape, but in new and unpredictable ways.

May we adapt in time before we lose any other great athletes? The pain is too heavy to bear already.