Alps rockfalls set for record after hot summer, scientist says

Rockfalls in the Alps are on course for a record year after the hot summer of 2026, with the Mont Blanc massif alone expected to record 450 by the end of the season, CNRS research director Ludovic Ravanel told AFP.

Ravanel said this year “will undoubtedly be a record year” for both the frequency of rockfalls and the volume of rock breaking away. The previous record was 300 in 2022, another year marked by heatwaves.

He said a large majority of the rockfalls can be attributed to the climate crisis. Rising temperatures are degrading and reducing permafrost, he said, weakening ice lodged in cracks in the rock that helps hold mountain walls together. Glacier melt can also reduce pressure on rock walls, making them less stable, he said.

The destabilisation has increased risks for mountaineers. Several climbers have died since the start of the summer season. In July, two Czech tourists were killed in a rockfall on the most commonly used route up Mont Blanc, and in August a 31-year-old man died in a rockfall in the Mont Blanc massif.

Authorities closed two shelters used to climb Mont Blanc, a precaution also taken in 2022.

Temperatures are expected to fall at high altitude in the coming days, but Ravanel said heat absorbed during the summer could keep penetrating the ground until November, December or even January. He predicted the biggest rockfalls could come in autumn, though they are likely to be less frequent.