Mont Blanc rockfall recorded by French guide underscores permafrost melt

French mountain guide Christophe Dumarest filmed a massive rockfall on the French side of Mont Blanc at the Aiguille des Grands Charmoz. A large slab of rock detached from the steep slope and collapsed, creating dramatic footage that spread online.

Scientists say the incident was triggered by unusually high temperatures that accelerated the thawing of permafrost – the permanently frozen ground that normally binds rocks together in high‑altitude environments. As the permafrost melts, the risk of rock detachments and landslides rises, a trend now being observed across the Alpine range and linked to climate‑change effects on mountain ecosystems. No injuries were reported.