Mont Blanc loses more than a metre in height in a year

Mont Blanc, western Europe’s highest mountain, has lost 1.29 metres in height over the past year, with its summit now measuring 4,807.47 metres above sea level, according to a team of French surveyors.

The latest measurement, announced on Wednesday, puts the peak lower than its 2025 level, although its height fluctuates annually as weather conditions alter the snow and ice covering the summit.

Surveyors from France’s Union Nationale des Géomètres-Experts and Ordre des Géomètres-Experts have monitored the mountain regularly since 2001. During an expedition last month, they used satellite technology and drones to measure the summit and create a detailed model of its snow and ice cap.

The latest figure is 3.43 metres below the record height of 4,810.90 metres recorded in 2007. However, the summit is still 1.88 metres higher than it was in 2023, when measurements reached their lowest level in recent years.

Summit measurements do not tell the whole story

Experts cautioned against interpreting annual changes in Mont Blanc’s height as a direct indicator of the wider loss of Alpine ice caused by climate change.

Changes in the summit’s surface elevation are not necessarily equivalent to changes in the total volume or mass of ice, a spokesperson for the surveyors’ union said. A higher summit, therefore, does not mean the mountain has gained ice overall or contradict evidence of retreating Alpine glaciers.

The latest measurements come amid growing concern over the effects of rising temperatures on Europe’s mountain regions. Earlier this month, Swiss glaciologists reported that the country had lost around one-fifth of its glacier ice over the past five years, with a further 5.5% lost between 2025 and 2026.

Jean des Garets, president of the Haute-Savoie departmental chamber of surveyors and leader of the Mont Blanc expedition, said the effects of warming were clearly visible elsewhere in the Alps, although the impact appeared less pronounced above 4,000 metres.

He described how the Tête-Rousse glacier had retreated, leaving streams in places where climbers had previously crossed ice.

The findings highlight the distinction between fluctuations in the height of Mont Blanc’s snow-covered summit and the longer-term retreat of glaciers across the Alpine region.