Why should I measure the height of Everest again
Guangming Daily reporter Yang Shu
The northern slope of Mount Everest in May was still snowy and bitterly cold. At the moment, 35 Chinese surveying mountaineers were struggling to climb upwards with heavy weight.
On the afternoon of May 6, the surveying mountaineering team composed of China National Surveying Team and the Chinese mountaineering team officially launched the summit of Mount Everest in 2020. In the next few days, they climbed from the bead of about 5300 meters above sea level. Starting from the second peak camp, it will pass the East Rongbuk Glacier, the middle camp, and the forward camp, and then arrive at the camps 1, 2, and 3 at an altitude of 7028 meters, 7790 meters, and 8300 meters. Finally, the opportunity to launch an attack on the summit of Mount Everest is officially Everest "measure height". As of the evening of May 7, the team members had traveled to the advance camp at an altitude of 6,500 meters.
What conditions are needed for accurate measurement?
Since the founding of New China, Chinese surveying and mapping workers have carried out 6 large-scale surveys and scientific surveys on Mount Everest, and have successfully measured and published the elevation of Mount Everest twice in 1975 and 2005. In 1975, the elevation of Mount Everest was measured. For the first time in China, the measurement target stood at the top of Mount Everest, and the elevation of Mount Everest was accurately measured at 8884.13 meters. In 2005, the Everest elevation re-measurement, our surveying team used the traditional geodetic survey and satellite survey technology, and for the first time in the Everest summit survey using ice and snow radar detector to measure the thickness of ice and snow, after rigorous calculations to obtain Mount Everest The elevation of the top rock face is 8844.43 meters above sea level. This data has become the authoritative data used in China's administrative management, news dissemination, foreign exchanges and other activities as well as publicly published maps and teaching materials, which is familiar to everyone.
However, as various technologies advance by leaps and bounds, more precise measurements become the goal. Xu Yongqing believes that re-accurate determination of the height of Mount Everest is an urgent and important historical task facing surveying and mapping workers. The accurate determination of Mount Everest's elevation can end the chaotic situation in which Mount Everest's elevation is not uniform internationally, and contribute to the world's earth science research. Its social benefits and scientific significance are very great. At the same time, with the advancement of science and technology, such as GPS technology, radar sounding technology, geoid refinement, absolute gravity measurement technology, meteorological detection technology, mountaineering equipment technology and geoscience theoretical methods, for more accurate measurement of Mount Everest elevation Created the necessary conditions.
In addition, the elevation of Mount Everest and the study of crustal deformation in the adjacent area have important theoretical value in geoscience research, "It will be used to study the interaction between the Indian Ocean plate and the Asia-Europe plate, and is also important for future earthquake prediction and disaster prevention Practical significance. "Xu Yongqing said.
Why did you choose this year?
Why test Everest again this year? According to the person in charge of the Ministry of Natural Resources, in October 2019, the "Joint Statement of the People's Republic of China and Nepal" was released, which proposed: Considering that Everest is an eternal symbol of the friendship between China and Nepal, the two sides are willing to promote climate change and ecological protection And other cooperation. Both sides will jointly announce the elevation of Mount Everest and carry out scientific research cooperation. As a result, the Ministry of Natural Resources, together with the Ministry of Foreign Affairs, the State Sports General Administration and the Tibet Autonomous Region Government, organized the 2020 Mount Everest elevation survey.
The Mount Everest elevation measurement coincides with the 65th anniversary of the establishment of diplomatic relations between China and Nepal and is a new measure to develop friendship between the two countries. This year is also the 60th anniversary of the first human climb to the summit of Mount Everest from the northern slope, and the 45th anniversary of the first accurate determination and publication of the Mount Everest in China. Therefore, it is of great historical significance to carry out the Mount Everest elevation measurement. "In addition, the measurement of Mount Everest in different ways at different times and the multiple measurements of the height of Mount Everest reflect the spirit of human knowledge and exploration, which has become an important symbol for human understanding and understanding of the earth." People said.
How to carry out the measurement? The reporter learned that on the technical route, this Everest survey will comprehensively use GNSS satellite surveying, precision leveling, photoelectric ranging, snow depth radar surveying, gravity surveying, astronomical surveying, satellite remote sensing, refinement of the geoid, etc. A variety of traditional and modern surveying and mapping techniques to accurately determine the height of Mount Everest. In terms of specific operations, after climbing the summit of Mount Everest, the mountaineering team members will erect a survey target on the top of the peak within 40 minutes, and use it as a target to carry out GNSS surveys and snow depth surveys. The mountaineers at the 6 intersections of the base camp on the north slope of Mount Everest, the Zhongrongbu Glacier, and the West Rongbu Glacier will also aim at the peak measurement target to carry out the measurement simultaneously. In the end, the survey team will summarize the measurement data at multiple points and after rigorous calculations, the latest measured height of Mount Everest will be obtained.
The relevant person in charge of the Ministry of Natural Resources commented that every time Everest measured, it reflects the continuous progress of China's surveying and mapping technology. "This survey will not only allow the surveying and mapping team to climb to the top, but will also rely on the Beidou satellite navigation system, aviation gravity technology and real-world 3D technology to carry out the survey. Domestic surveying and mapping instruments and equipment will also fully cover this survey task. The above are innovations and breakthroughs. "
Who is the warrior of Everest again?
Shiluo, Yuan Fudong, Xue Yun, Tsering Sangzhu, Pu Budunzhu ... A total of 35 surveying mountaineering team members from this expedition came from the national test team and the Chinese mountaineering team. "This is a powerful combination of the two hero teams." The person in charge of the Ministry of Natural Resources commented. On May 25, 1960, the Chinese mountaineering team successfully climbed Mount Everest from the north slope, marking the first time that humans climbed Mount Everest from the north slope.
In addition to the peak, the six sites measured at this time are all above 5200 meters above sea level, and the atmospheric oxygen content is only 70% of the inland. Even if empty-handed, people are as burdened as carrying a 30-kilogram weight, making climbing difficult. In order to overcome the severe conditions of high cold and lack of oxygen, and at the same time ensure that the heavy measuring instruments are carried on the Everest by hand, the mountaineering team members have previously conducted a series of mountaineering training and alpine surveying training. At the same time, the 53 surveying and mapping members of the national surveying team have carried out leveling, gravity, GNSS, astronomy and other surveying work in Everest and surrounding areas since March 2, and completed leveling, encrypted gravity measurement, absolute gravity At the same time, the satellite navigation and positioning of the temporary reference station were continuously deployed at the same time, and the basic surveys such as surveying, burying, and elevation transmission of the six Everest elevation measurement intersections were completed. At present, the peripheral measurement tasks of Everest have been basically completed .
The march continues. According to the surveying mountaineering team, according to the weather forecast, the "window period" of the first summit of Mount Everest will be ushered in after May 10, when the team members will seize the opportunity from Camp No. 3 to attack the summit.
"Guangming Daily" (Version 04, May 09, 2020)