Glacier Monitoring Switzerland (GLAMOS) has measured the ice on 20 glaciers ranging throughout Switzerland since the year 1915 and have analyzed the data each year. Overall, they measure the net accumulated ice throughout the winter, ranging from October 1 – April 30. They then also measure the ice loss throughout summer, ranging from May 1 – September 30.
The recent years 2022, 2023, and 2024 were outliers. The winter of 2024 was an especially strong one, bringing the largest glacier mass gain since 2000. But that gain was quickly undone. Warm summer months and other contributing factors led to significant losses, despite the substantial snowpack built over the winter. July and August were particularly warm, with August 2024 seeing the largest ice loss of any August since 2000. One key factor was the presence of Saharan dust, which settled on the snow and accelerated melting. If you’ve skied in the spring, you’re probably familiar with that stubborn end-of-season dirty snow, it lingers and never seems to melt cleanly. Not only does it make for less enjoyable, sticky skiing, but it also absorbs more UV radiation, heating up the snowpack and speeding up melt. That’s exactly what happened in the Swiss Alps, especially at Claridenfirn, where thick layers of Saharan sand blanketed the glacier.
As you can see, the only positive change (the glacier size increases) was recorded in 2000 with a .2 km3 increase. Every year since, the net ice volume has decreased. The years of 2002, 2022, and 2023 are the largest outliers in total ice loss.
This graph illustrates the compounding effects of ongoing ice loss. Take 2024 for example, while the net loss that year may appear average on its own, it becomes far more significant when measured against the greatly reduced ice volume after 23 years of steady decline. As shown in the graph, total ice volume has dropped from 74.9 km³ in 2000 to just 46.4 km³ in 2024. That is 28.5 km3 or a 38% decrease over merely 24 years.
Looking at 2025, it was a moderate change with snow accumulations at 13% below the 10-year reference period. This also includes the massive 2-meter storm that occurred this past April in many of the Swiss alps, including in Zermatt where the town underwent an interlodge. This very moderate winter has not brought a moderate summer. Already very warm temps throughout early summer have melted all the snow that accumulated this past winter for the “Glacier Loss Day” of July 4. If trends continue, the rest of the summer could be another debilitating event for the Swiss glaciers.
So the Swiss glaciers are melting, why is this an issue? In Switzerland, these glaciers and their water runoff are vital for the water management of the county. As the glacier disappears, there will continuously be less water runoff to support the country especially in times of drought. Skiers and snowboarders depend on these snowpacks for available winter terrain. Yes, there is still a deep snowpack in higher elevations, but the skiable elevation is rapidly rising. Most importantly, the studies of these Swiss glaciers show a bigger picture of what is happening in the world. The world is warming, ice is melting, and climates are more extreme and unpredictable. If global temperatures continue to rise due to human activity, these warning signs—from disappearing glaciers to unstable weather—may soon cross a tipping point, leading to irreversible and potentially catastrophic consequences for ecosystems, communities, and the future of winter itself.
