No change in the height of the Matterhorn

One of the points used in the Aufdenblatten points out, survey was the cross at the peak “the measurement uncert- of the Matterhorn, shown here ainty of the cumbersome with an SR500 lashed to it. opto-mechanical triangula- tion methods then in use was several decimetres at these distances“. In addition allowing height and position to greater precision, such changes of this prominent cross-border surveying Swiss-Italian landmark to projects have also provided be precisely tracked. It is evidence of discrepancies apparent that this part of the between national geoids, Alps will continue rising which could be reconciled faster than the annual rate over the medium term. of erosion. Poretti detected a “border ments on the peak and in Taking up position at the peak of step“ of 27 centimetres the Nepalese and Tibetan A century of surveying history the Matterhorn. 27 centimetres between between Italian and Swiss valleys – to redefine the countries geoid data. height of Mt. Everest at Experts with an eye for surveying history saw the 8846.10 metres above sea Matterhorn measurement as symbolic of a technological The Matterhorn is precisely 4477.54 metres high – and According to Urs Marti of Ancient African rock level. Problems with metre- revolution. It was here in canton Valais, within sight of remains at 4478 metres according to the maps. In the the Swiss Federal Survey, high layers of snow and ice the Matterhorn, that Heinrich Wild, topographer and later September 1999 re-survey featured in a recent “Reporter“, the height of the Matterhorn Confirmation of the 4478 covering the peak of Everest instrument designer, used an enormous, mechanical Italian geology professor Giorgio Poretti was the first to was originally determined in metre height means that the were not an issue on the repetition theodolite on the Dents-du-Midi to chart the position a GPS surveying system on the peak, with the 1920s. Back then, Matterhorn, formed of rock Matterhorn. lower Valais in 1902. Struck by the laboriousness of this LEICA GPS500s at reference points in the valleys on either Zermatt’s local landmark originating from what is Stf method, he went on to develop lighter, opto-mechanical side. All points were additionally measured using optical was measured at 4477.50 now Africa, has been spared instruments like the Wild T2 is the forerunner of the laser triangulation. metres and declared on the numerical indignity modern electronic tacheometer – give or take little extras official Swiss maps as being recently suffered by Kiliman- like laser technology, electronic angle measurement and 4478 metres above sea jaro (see Reporter 44). sophisticated software. The Matterhorn is the level. Yet as Zermatt-based world’s third mountain, after geometrician Klaus Giorgio Poretti took a WILD T2 along with a LEICA GPS500 Mt. Everest and Kilimanjaro, to the peak of the Matterhorn and used it to sight down to be re-surveyed using the to the valley, where further GPS500 systems were latest technology based on The highest mountains on the six continents complemented by LEICA T2002, LEICA DI3000 and LEICA GPS, the Global Positioning TCA2003 electronic theodolites and infrared distance System. The height of the Continent Highest mountain Height above measurement equipment. Giorgio Poretti was also sea level Matterhorn is now known interested in comparative measurements as a means of Asia Mt. Everest 8846 metres * with centimetre accuracy, determining whether, and by how much, rays in various America: Aconcagua 6959 metres ** parts of the electromagnetic spectrum (GPS microwaves, Africa: Kilimanjaro 5892 metres * A LEICA GPS500 in the valley on DI3000 infrared laser light, T2 visible light) were affected Antarctica: Mt. Vinson 5140 metres ** the Italian side. The “Cervino“, by the atmosphere at great differences in altitude as they Left: The measurement setup at Europe: Mont Blanc 4808 metres ** as the Matterhorn is known in travelled to and from a prominent and isolated mountain the peak of the Matterhorn: Australia: Mt. Kosciusko 2230 metres ** Italian, looks completely LEICA GPS500 and reflectors for like the Matterhorn, and whether these effects could be different from this viewpoint. the tacheometers in the valleys * Surveyed using LEICA GPS 300/500 during the last decade; used to indicate meteorological changes. ** Surveyed using Leica Geosystems theodolites during the last century on either side. In October 1999, an expedi- tion led by Eberhard Messmer also used LEICA GPS500 systems to deter- mine a new height of 5892 metres, superseding the earlier figure of 5895 metres. The Swiss Federal Survey map And eight years ago, Giorgio was used to pinpoint the Poretti and Yun-Jong Chen precisely defined station point used a similar measurement in Zermatt for the Matterhorn configuration – with instru- re-survey.

Measurements from the valley Drifting continental plates on the Swiss side (Zermatt) caused ancient African rock to were taken simultaneously with tower up into what is now a LEICA GPS500 and TCA2003. the Matterhorn. 12 13