Swiss know-how adds two metres to America’s highest peak

Mount Aconcagua. Clive Mowforth

Technology designed by the Swiss firm, Leica Geosystems, has revealed that the highest peak in the Americas is taller than previously thought.

An Italian-Argentinian scientific expedition, led by geologist Giorgio Poretti, was dispatched to the Andes Mountains last month to provide the most accurate measurement to date of Mount Aconcagua.

The giant peak holds a special place in the hearts of Swiss mountaineers, since the first man to conquer it in 1897 was a mountain guide from Saas-Fee, Mathias Zurbriggen.

Using the latest global positioning (GPS) equipment, developed by Heerbrugg-based Leica Geosystems, the team determined the exact height of the summit to be 6,962 metres – an increase of two metres on previous measurements.

GPS surveying equipment, designed by the Swiss firm, has been used on previous expeditions to determine the true heights of Asia’s Mount Everest and Africa’s Mount Kilimanjaro.

On both occasions, the peaks were found to lie at an altitude of two metres less than previous measurements had indicated. Poretti’s team had been looking to see whether this “shrinking” trend applied to Mount Aconcagua – which was thought to be 6,960 metres high.

“This, however, was not the case,” said a spokesman for Leica Geosystems, “but the results still do not indicate that the Andes are growing at a greater rate than the Himalayas.

“From now on, however, with technology and systems providing a reproducible accuracy of a few millimetres, it will be possible to precisely measure the summits and record their vertical and horizontal movements.

The portable Leica GPS System 500, which was used by Poretti’s team of geologists, glaciologists, surveyors and climbers, uses microwave signals emitted by satellites to measure altitude to within a few millimetres.

swissinfo