At 8, meters 29, feet , it is considered the tallest point on Earth. In the nineteenth century, the mountain was named after George Everest, a former Surveyor General of India. They climbed the mountain in and hold the record together. British surveyors recorded that Everest was the tallest peak in the world in their Great Trigonometrical Survey of the Indian subcontinent. The Himalayan mountains have long been home to indigenous groups living in the valleys. The most famous of these are the Sherpa people.
The Sherpa have valuable experience in mountain climbing, which they can provide to other climbers. However, their way of life extends beyond helping Everest climbers. Traditionally, their lifestyle has consisted of farming, herding, and trade. And, because they live at such a high altitude year round, they are accustomed to the low oxygen levels. Climbing Mount Everest has become a popular expedition for mountain climbers.
However, it is a dangerous undertaking. Climbing Everest requires a lot of experience mountaineering elsewhere, as well as a certificate of good health, equipment, and a trained Nepalese guide. The snow and ice on the mountain create deadly hazards like avalanches, and there is only a limited climbing season due to bad weather conditions. But perhaps the biggest danger is the altitude.
Most climbers are not accustomed to the high altitude and low oxygen levels and rely on bottled oxygen they bring along. With more people has also come more pollution up near the summit as climbers often discard unwanted items all along the mountain. Additionally, the Sherpa people have been exploited by climbers, and their traditional way of life has been disrupted by foreign climbers.
Sherpa guides are faced with some of the highest death rates of any field of employment, for comparatively little pay. Most disturbingly, because many climbers have died along the way, and their bodies are impossible to retrieve, climbers must frequently travel past corpses as they make their way up the mountain. Mount Everest is part of the Himalaya and straddles the border of Nepal and China.
Sherpa often serve as mountaineer guides and porters on mountain-climbing expeditions. The study from Chinese researchers corrected the future projections of current global climate models that have underestimated the anthropogenic warming of the Plateau. According to their results, the Tibetan Plateau could witness much higher warming than previously projected. The findings of this research were published in the Environmental Research Letters recently. Notably, this will lead to greater glacier retreat and will also disrupt the water supply for billions of humans, animals, and flora species along rivers like the Ganga and Brahmaputra in India, the Indus in Pakistan and the Yellow and Yangtze in China.
The melting of these glaciers, that represent centuries of snow compressed over time into slowly flowing rivers of ice, not only contributes to rising sea levels but also alters the flow of rivers — which has economic and social consequences as they affect agriculture and the production of hydroelectricity. This is a matter of a grave concern. While initially melting glaciers can be interpreted as a good sign due to an increase in streamflow, they eventually reach a tipping point, called peak flow, after which the meltwater starts to taper.
These lozenges of lithosphere were aided by the eastward movement of subduction trenches in the Pacific Ocean to the east of what is now China. Crustal movement Eventually, around 20 millions years ago, the trenches halted in their eastward march. As India and Eurasia continued to collide, "stuff couldn't leave to the east," Royden explained.
While some geologists think crustal shortening continued to build up the eastern plateau, Royden says there is little evidence for this, and that the pile-up of lithospheric material underneath the plateau continued to thicken the crust and raise the eastern portion of the plateau. Whether or not the subsurface material is flowing faster or slower now, geologists aren't sure, Royden said.
Studies of the rates at which rivers have cut down through the rock in these areas may help geologists to suss out the vertical motions of the plateau. Tibet and the Sichuan quake The movement of the lithosphere under the plateau could also be behind the Sichuan earthquake , Royden said.
The area where the quake occurred is traditionally considered one of low seismic risk, Royden said. Some geologists have said the quake was a result of traditional thrust faulting, where one piece of crust is pushed up over another.
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