We all know that Mount Everest is the highest mountain in the world but over the years it has been measured many times using the latest available technology at the time giving slightly different results. In 1856 Andrew Waugh declared Peak XV as it was called in those days to be 29,002 feet high based on his computations and observations through Great Trigonometric Survey.
The height of the Mount Everest as mentioned in the article is 8, 848 which has been recognized officially in both China and Nepal. After many years of calculation and measurements, on the 9th October 2005 the State Bureau of Surveying and Chinese Academy of Sciences made an official announcement that the height of Mount Everest was actually 29,017.16 feet or 8,844.43 meters with accuracy of ±0.69 feet (0.21 meters).
It was claimed to be the most precise measurement ever taken. This height is based on the top of the rock on the summit of Mount Everest and does not include the ice and snow which covers it. They also measured the ice and snow depth of 11 feet which increases the net height to 8,848 meters. The ice and snow thickness can vary over time and it is not possible to find out the precise height of snow cap.
The elevation of Mount Everest as 29, 029 feet was found out during 1955, by Indian survey with the use of theodolites that was accurate. It was then reassured by Chinese measurement during the year 1975 which also stated the height as 8,848.13 meters. In both measurements, the snow cap was considered and they did not measure the rock head. An American Expedition was conducted during the month of May in 1999, headed by Bradford Washington, who grounded a GPS unit to the top most bed rock. The elevation till rock head was found to be 29, 035 feet (8, 850 meters) and the snow cap elevation was found to be 3 feet (1 meter) higher with the help of this GPS device. Though it was recognized by Nepal officially, it is quoted widely. Geoid casts of uncertainty doubt upon precision of results claimed by surveys conducted during year 2005 and 1999.
It is considered that tectonic plates of the regions are incrementing the height of region as they move the summit in north east direction. There are suggestions that rate of increase is 4 millimeters per year in upward direction and 3 to 6 millimeters in northeast direction and there is another theory suggesting lateral movement of 27 millimeters an year.
Today the height of 29,029ft (8,848m) is officially recognized as the correct elevation by Nepal, China and many from around the world.
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