Heatwave in France: 2026 sets rockfall record in the Alps

The summer of 2026 saw an unprecedented number of landslides in the French Alps, especially around Mont-Blanc, due to extreme heat and thawing permafrost. Long seen as the safest time of year for mountaineering, summer has in recent years become a high-risk season. In the Alps, 2026 already holds a worrying record: 450 rockfalls in the Mont Blanc massif alone since the start of the year. An unprecedented situation for Ludovic Ravanel, a geomorphologist and research director at France's CNRS, within the Edytem laboratory: "Here temperatures have easily topped 30-35 degrees, and that obviously has an impact on the glaciers and on the permafrost. That is why this year we are seeing record numbers of destabilised rock faces and of collapses on the cliffs." The previous record dated back to 2022, with 300 rockfalls recorded that year. This phenomenon is directly caused by climate change, explains Ludovic Ravanel: "We have almost 200 years of climate warming documented in these photographs. By comparing them, we can identify the scars, in other words the areas where the rock faces have become unstable. We can measure them in terms of volume, and we have shown that 80 or 85% of these scars have formed over the past two or three decades. So there is a very clear link between a warming climate and the destabilisation of rock walls." These heatwaves, which are becoming ever more frequent and prolonged, are also weakening the mountains in depth. "Rock collapses and rock avalanches today occur mainly because of degrading permafrost, but also because glaciers are retreating. Glaciers tend to exert pressure on the slopes, and that pressure is rather stabilising. When glaciers lose thickness, on the contrary, the rock faces decompress," the geomorphologist adds. In July, two Czech tourists were killed in a rockfall on Mont Blanc, and in August a man also died in similar circumstances. For now, experts and local authorities are not considering restricting access to the high mountains, but they are urging climbers to remain vigilant, as rockfalls could still be frequent in the coming months.