Mont-Blanc: how is the height of the mountain measured?

A team of experts is setting out this week to conquer the highest mountain in Europe to measure its exact altitude, down to the centimeter.

A team of experts will climb this week to measure the exact altitude.  (illustrative image)
A team of experts will climb this week to measure the exact altitude. (illustrative image)

Ua new ascent of Mont-Blanc which will be closely scrutinized. As reported by BFMTV, expert surveyors have launched an attack on the highest mountain in Europe, approximately every two years since 2001, to verify the precise height of its summit. To do this, you must start by finding its highest point, the summit ridge being almost at the same horizontal level over a hundred meters long.

“We walk around this area by pointing a GPS attached to a cane as close to the ground as possible. Thanks to a tablet giving us the altitude under our antenna, we determine the exact summit,” explains Denis Borrel, president of the commission in charge of this 12th measurement of Mont-Blanc, to our colleagues. Once the exact point has been identified, the rod holding the GPS is inserted there and you then have to be patient to obtain the altitude to the nearest centimeter.

“We obtain altitude corrections in real time via other GPS, static and anchored in the valley, which send their signals via the internet and satellites,” explains Denis Borrel. “From the measurement carried out on Friday, the IGN must subsequently refine the calculation taking into account the actual zero level below this point. Concretely, this zero altitude differs slightly from sea level under rock masses, such as mountains, due to the Earth’s magnetic field,” he adds.

READ ALSO Mont-Blanc: landslides are increasing due to global warming

A previous mark at 4807.81 meters

In 2021, during the previous measurement, the summit of Mont-Blanc peaked at 4807.81 meters, or 92 centimeters less than the previous readings. A loss of height which cannot be explained by the effects of global warming according to the expert: “Everything depends on the influence of the wind, which shapes the summit depending on the side from which it blows. Scientists have drawn no conclusions and consider the top of Mont Blanc to be a fridge, with no significant melting observed.” This year, the new official size of the Alpine giant could be announced on October 5 at a press conference.

READ ALSO A bivouac at the summit of Mont Blanc causes an outcry

Leave a Comment

Your email address will not be published. Required fields are marked *