PRESS RELEASE of the Swiss Foundation for Alpine Research, 12 November 1999
"Complemented version of 30 November 1999"
Elevation of Mount Everest newly defined:
8,850 not 8,848 meters above sea level
On November 11, 1999, at the "Mount Everest Evening" of the National Geographic Society and the American Alpine Club, Dr. Bradford Washburn, honorary director of the Boston Museum of Science and member and correspondent of the Swiss Foundation for Alpine Research, announced the newly established elevation of the worlds highest peak: 8,850 meters or 29,035.3 feet, which is two meters more than the previous official figure of 8,848 meters or 29,028 feet.
The three-dimensional determination of the famous peaks exact position, which was initiated by and carried out under the management of Bradford Washburn, is based on a satellite-supported triangulation technique. In May of1999, the US expedition team Everest-Millennium, guided by six-times Everest conquerer Pete Athans, managed to anchor in the summit rock a receptor for satellite signals from the Global Positioning System (GPS) not an easy task which had failed several times since the project start in 1995 because of bad weather. Another GPS measuring point had already been anchored in 1996 in the south saddle of Mount Everest at an elevation of 7,930 meters or 26,017 feet. The simultaneous use of the two fixed stations and a mobile GPS receptor carried by the expedition members along the regular south col has allowed a position determination of unprecedented precision. The snow mass covering the summit of the mountain was excluded from the calculations because its height varies according to the intensity of the monsunes. To achieve this, a radar was carried up to Mount Everest which would determine the position of the rock. The snowy top adds an average of one entire meter to the peaks elevation, making it 8851 meters or 29,038 feet high.
The surveying and naming history of the worlds highest mountain started in 1853. At that time, the Bengali surveyor Radhanath Sikhdar announced to the office of Indias surveyor general, Sir Andrew Waugh, that he had discovered the highest Mountain on earth which then got registered as Summit XX. Sikhdars calculations were confirmed in 1856, and in 1865 Sir Waugh named the summit Mount Everest in honour of his predecessor, the surveyor general Sir George Everest. He thus ignored the existing names the Tibetans and Nepalese had already given it: Chomolungma, goddess of the earth, and Sagarmatha, goddess of the sky respectively.
The then calculated elevation of 8,840 meters or 29,002 feet represented an average of data obtained through six different surveying stations, all located at a distance of 170 to 190 kilometers (105 to 118 miles) from the Everest massif at about 60 meters or 197 feet above sea level. In 1954 the official elevation of Mount Everest was set at 8848 meters or 29,028 feet. This figure was established by the Survey of India and consisted of the average data obtained from a total of twelve surveying stations located between 47 and 76 kilometers (29 to 47 miles) from the mountain. In September 1992, the first modern elevation survey was performed directly at the mountain by a Chinese-Italian expedition team. They collected data using not only the regular Swiss theodolites but also laser altimeters and GPS signals. The newly established elevation was surprisingly close to the old figure: 8,848.82 meters or 29,031 feet.
The GPS-supported position measurements carried out in May of 1999, which established the elevation of the Everest summit at 8,850 meters or 29,035.3, were not only exact to the centimeter but could also calculate the continuous movement of the peak due to the continental drift . The "infiltration" of the Eurasian continental platform by the Indian subcontinent goes on and is the cause for the rising and shifting of the Himalaya massif. Based on the results from the first GPS measurements at the south saddle of Mount Everest (at an elevation of 7,930 meters or 26,017 feet) four years ago the expert team concluded that the Everest massif rises at least 4 millimeters or 1.5 inches per year. However, at a recent press conference Bradford Washburns explained that the elevation of Mount Everest has not changed but that the mountain has been moving 3 to 6 millimeters or 12 to 24 inches per year in the north-eastern direction. Still, the regional tectonics have led Bradford Washburn to the conviction that Mount Everest and the entire Himalaya massif have been gaining elevation over the years, millimeter by millimeter. The question remains whether erosion compensates for the gross growth over time. Besides the alpinistically rather curious fact that each new Everest-conqueror has virtually climbed higher than those before him, other useful information has been drawn from the latest GPS-supported Everest survey (in connection with many other survey data of the Himalaya massif): seismologically relevant data of the continental drift was obtained, which constitutes an important contribution to the research of earthquakes and their causes.
Thanks to Bradford Washburns inspiring enthusiasm for the worlds mountains many a map project was completed over the years in collaboration with the Boston Museum of Science, the National Geographic Society, the University of Alaska Press, the Department of Topographic Survey (Bundesamt für Landestopographie), the surveyors of Swissphoto, and the Swiss Foundation for Alpine Research. The latest result of this collaboration is the
Mt. Everest Orthophoto Map 1 : 10 000
Camp 2 to the Summit via the South Col
the first map marking the summit elevation as
8850 meters or 29 035.3 feet above sea level
This special map of the Everest summit region is based on aerial photographs taken from an altitude of 12,000 meters (about 40,000 feet) and published in the form of two planographic prints (a photograph of the Everest summit model and a digitized orthophotograph). The map can be ordered at the Swiss Foundation for Alpine Research, Binzstrasse 23, CH-8045 Zurich, phone +41 (0)1 461 01 47, fax +41 (0)1 461 07 11, e-mail: email@example.com or, even easier, at our On-line Shop.
The following links provide an in-depth look at the adventurous expedition project of the Mount Everest elevation survey:
(Note: The website of the Austrian television station ORF points out a fascinating geological observation made by scientists of the Kyushu University, Japan: having analyzed rock samples from faults on the north side of Mount Everest, at an elevation of 8,500 meters or 28,000 feet, they argue that twenty million years ago the summit is likely to have throned at a majestic 15,000 meters or 50,000 feet before embarking on a remarkable slide.)
National Geographic Society
Boston Museum of Science
ORF zu Everest
Trimble GPS Company
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