Officials at Nepal's foreign ministry and department of survey said surveyors from both countries had co-ordinated to agree on the new height. The agreement to jointly announce the new measurement of the Earth's highest point was made during Chinese President Xi Jinping's visit to the Nepalese capital, Kathmandu last year. Chinese authorities had said previously Mount Everest should be measured to its rock height, while Nepalese authorities argued the snow on top of the summit should be included.
The Chinese surveyors had calculated their figure after they measured the mountain in Nepal's government officials told the BBC in that they were under pressure from China to accept the Chinese height and therefore they had decided to go for a fresh measurement to "set the record straight once and for all".
The 8,m height Nepal had been using for Mount Everest was determined by the Survey of India in , but for the first time the country has now conducted its own measurement of the summit.
Four Nepalese land surveyors spent two years training for the mission, before heading to the summit. Nepal's lead surveyor Khimlal Gautam lost his toe due to frostbite while on the summit to install height-measuring equipment last year. Why else has the height been questioned?
Some geologists have suggested a major earthquake in may have had an impact on Mount Everest's height. The 7. At least 18 climbers were killed. Some geologists said the earthquake may have caused Everest's snow cap to shrink. Scientists had found that some other Himalayan peaks such as Langtang Himal, mostly to the north of Kathmandu and close to the epicentre, had reduced in height by approximately a metre after the earthquake.
Others have argued that Mount Everest, like other Himalayan peaks, may have actually grown over time because of the shifting tectonic plates it sits on. This new height converts to 29, The earlier accepted height was 8, metres or 29, feet. Chinese Foreign Minister Wang too announced the mountain's height to be 8, The margin of error is within centimetres. A range of methods including traditional ones and those based on the latest technology were used to come up with the figure.
This will be a commonly accepted height. During these triangulation observations, the Himalayan peaks of Nepal were also observed. At that time it was not known that this peak in the Himalayas was the highest in the world. During computations, the mean computed height of Peak XV came out to be 29, ft, or 8, The widely accepted height of 8, metres or 29, feet was determined by the Survey of India in from Bihar using the trigonometric method.
It was the third survey conducted by India. In , a Chinese survey of the mountain estimated that it stood at around 8, meters about 29, feet. However, since the research was not authorized by Nepal, the country did not recognize it as the official height.
At the time, they were using a figure of 8, meters 29, feet , in line with the findings of a Indian survey. Then in , multiple scientific studies suggested the mountain's elevation may have changed after a 7. Mount Everest is 29, That is more than two feet higher than the altitude previously recognized by the government of Nepal.
The elevation, which was announced on December 8 in a joint statement by the Survey Department of Nepal and Chinese authorities, is the culmination of a multiyear project to definitively measure the legendary mountain.
As the first serious survey of Everest in 16 years, the effort has been closely followed by the geographic community—particularly scientists analyzing how a devastating 7. Find out why Mount Everest changes height.
Last spring a small group of Nepalese surveyors and guides endured the biting cold of a nighttime ascent, reaching the top at 3 a. Find out exactly how the teams made their measurements, and the challenges they faced during the expedition.
In , mathematician Radhanath Sickdhar found that Everest is the highest mountain in the world while he was working for the Great Trigonometrical Survey, a project dedicated to surveying and mapping the Indian subcontinent. Until the advent of satellites, surveyors used a device called a theodolite, a precision optical instrument mounted on a tripod, for measuring angles between two designated points. A survey using a similar technique calculated that Everest stands at 29, feet above sea level, a number that is still recognized by many countries and map publishers.
Then in a survey led by cartographer and explorer Bradford Washburn, and sponsored by the National Geographic Society, was the first to use GPS technology to measure the Everest summit.
The figure will be used in all publications and re-publications going forward, including National Geographic-branded maps and atlases. To make their new survey as complete as possible, the Nepalese team decided to employ both previous techniques. On May 22, , Gautam summited Everest with four teammates and deployed a GPS receiver, along with ground-penetrating radar to measure the depth of the snow piled on top of the rock.
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