The snow and ice that Swiss glaciers built up over the entire winter are expected to be gone by Monday. That marks what scientists call glacier loss day, the point at which all further melting shrinks the glaciers themselves. It is arriving this year on the second-earliest date ever recorded, according to a report by AFP.
The only year the tipping point came sooner was 2022, when it arrived on June 26. On average this century, glacier loss day has fallen in mid-August. The shift from mid-August to late June represents a dramatic compression of the protective snowpack season.
Matthias Huss, the head of Glacier Monitoring in Switzerland, known as GLAMOS, described what is driving the damage. "We're just seeing enormous ablation, ice melt rates and snow melt rates all over the Alps," Huss told AFP on Friday, as multiple Swiss weather stations registered new all-time records. "We are three months too early compared to a healthy state."
Huss had just returned from the Rhone Glacier when he gave that assessment. In the 10 days since his previous visit, "there was one meter of ice melted in the vertical direction — one meter of melting within just the last 10 days," he said. "It's very impressive to see, and this is just the effect of the heat wave."
The situation is being driven by more than one heat event. A heat wave in May came first, eating through the snowpack earlier than normal. The current wave followed. Both arrived after a winter with poor snowfall. Huss also pointed to the arrival of Saharan dust in March as part of what he called a "combination of bad circumstances."
The physics make the problem self-reinforcing. When the white reflective snow cover melts away, the darker bare ice beneath is exposed. That surface absorbs radiation more quickly, which accelerates melting further. The process feeds on itself.
This year also saw 25% less snow replenishing the glacier surfaces compared to figures from 2010 to 2020. Huss said 2026 is "surprisingly similar" to 2022, which was "by far the most extreme year ever recorded in the Alps, with melt rates shattering everything we had seen before."
He offered a measured note on single events versus long-term patterns. "One heat wave alone is not a big problem for glaciers," he said. "The problem is rather that we have very high temperatures that last for a very long time. The more days that are added that are very high temperatures, not even mattering whether it's 35C or 40C, this is just very bad for the glaciers."
The stakes extend beyond the glaciers themselves. Much of the water that flows into the Rhine and the Rhone, two of Europe's major rivers, originates in the Alpine glaciers. The full scale of the damage from 2026 will be measured in September.
