Is Mont Blanc shrinking?

You might be surprised how much of a debate the simple question “How high is Mont Blanc?” can stir. We look at the latest data...

5m lower in 2023 than 2010

The height of Europe’s highest mountain changes continuously. In September 2023, it was officially measured at 4805.59 metres above sea level – five metres less than in 2010.

The figure was delivered at the end of a three-day mission by surveyors. They used satellite sensors to generate a precise figure for the height of the summit. The 2023 measurement was carried out by eight teams, bringing together 22 mountain experts.

Height of Mont Blanc is always changing

Search around the internet and you might see the official height listed as 4809m, but the truth is that the actual summit is always changing, depending mainly on recent weather conditions, but also marginally due to shifting tectonic plates.

About 15 metres of the summit of Mont Blanc consists of snow and ice.

It’s not just precipitation and temperature that affects how much of this sits at the top: wind plays a key part as well.

Ironically, this means the mountain is typically less high in winter, due to high winds blowing snow away.


General downward trend?

Bear in mind we are only talking about a small difference, but the highest recorded height of 4810.90 metres was in 2010. That’s 5.31 metres higher than the most recent measurement.

It does appear that there is a general trend downwards, with the last five measurements (over a ten year period) showing a decrease on the previous four.

The measurement for 2019 was so far from the trend that the surveyors deemed it ‘exceptionally low’ and it was not officially reported.

Next results due in September 2025

However, there as there is only  accurate measurements back to 2001, experts have warned that there is not enough data to establish if these changes are related to climate change.

The next two-yearly survey is scheduled for September 2025, so we will be closely looking out for these results.