CHAMONIX-MONT-BLANC, France: For centuries, glaciers and snow on Mont Blanc, Europe's highest peak, have defined the landscape and identity of Alpine communities in France and Italy, but climate change is now rapidly erasing that familiar picture.

Record-breaking summer heat is changing Mont Blanc in ways that are becoming impossible to ignore.

Across the Alps, rising temperatures are melting permafrost, retreating glaciers and weakening the frozen ground that has helped hold steep mountain slopes together for thousands of years. This summer, the effects were especially visible around Mont Blanc at 4,805 meters.

As the frozen ground thawed, sections of rock broke loose and fell from the heights. Rockfalls became more frequent, glaciers pulled back and new cracks opened in the ice. One well-known gully used by climbers on routes toward the summit became temporarily too dangerous to cross.

Stéphane Bozon, deputy mayor of Chamonix-Mont-Blanc and the town official responsible for safety, said the changes were deeply troubling. He said residents had watched rockfalls increase since mid-July, while melting snow and retreating glaciers made some areas harder and more dangerous to reach.

The warming is particularly striking at high elevations. On Aiguille du Midi, a peak in the Mont Blanc range that stands 3,842 meters above sea level, the average temperature in July reached 3.3 degrees Celsius. That was the highest July average ever recorded there. In 1994, the average was only 1.6 degrees Celsius.

Bozon said the mountain had become noticeably drier and warmer than anything he had experienced before. He warned that the town must prepare for serious situations, including the possibility that large pieces of ice or rock could fall toward populated areas.

Scientists say the danger is linked to permafrost loss. The frozen ground acts like natural cement, locking rocks together and helping keep mountain faces stable. When the ice melts, that support weakens. Researchers stress that this does not mean every mountain wall will collapse, but many areas could become unstable as the frozen ground disappears.

The changes are also being recorded on the Italian side of the Alps. In Lombardy, glaciers have lost more than 40% of their surface area since 1991. Researchers say warmer conditions are changing snowfall patterns, with rain increasingly falling at elevations where snow was once common. This is raising concerns about terrain stability.

For mountain guides, the changes are becoming a daily safety challenge. Stuart MacDonald, who works from Chamonix, said he is shocked by how quickly the glaciers have retreated. He now shows climbers where the ice ended a year ago and where it stood a decade earlier.

This summer, melting ice and falling rocks forced him to cancel a planned ascent of Mont Blanc. He said climbers can sometimes hear rocks crashing down before they see them, and routes that were safely used in July or August in the past can now be impossible to climb.