Why did the height of Mount Everest change?


Beijing – The highest mountain in the world is now officially a little higher, and that may not be the end of the story.

China and Nepal agreed this week on a new standard height for Mount Everest, the massive Himalayan peak that crosses their borders.

As definite as it may sound, geological changes, the complex undertaking of measuring the mountain, and the different criteria needed to determine the highest peak in the world are likely to provide a definitive solution to the issue.

The height of the mountain changes. The movement of tectonic plates can lift it up as gradually as earthquakes can bring it down.

Balancing forces can help maintain a degree of stability over time, said Dang Yamin, a member of a Chinese team that surveyed Everest’s height earlier this year.

“Nature tends to strike a balance,” he told the Xinhua official news agency. As an example, Dang cited a massive 1934 earthquake that instantly eliminated 150 years of constant elevation.

There are several ways to measure a mountain. Last year, a Nepalese team set up a satellite navigation beacon at the summit of Everest to use GPS satellites to assess its exact position. A Chinese team undertook a similar task this spring, although it used the constellation of Chinese-made Beidou navigation satellites in conjunction with other equipment.

At the same time, Nepalese personnel made measurements with modern, laser-equipped versions of instruments called theodolites, which were first used in 1856 to determine the height of a mountain by trigonometric measurement of angles.

The Nepalese team also used ground radar to measure the amount of snow and ice sitting on top of the highest cliff.

China and Nepal have introduced a new official number, 8,848.86 meters (29,031.69 feet) above sea level. The agreement, announced on Tuesday, was announced as a sign of growing political, economic and cultural ties between the two countries.

The new altitude is 0.86 meters (more than 2 feet) higher than the country’s two previous values ​​given by Nepal. Two deviated from the actual height of the mountain for a year.

Measuring altitude has always been difficult because ocean levels vary significantly depending on tides, magnetism, and other factors. Sea level rise is another factor for future measurements.

How high it is above sea level is just one way to measure the height of a mountain. Everest is one of the reasons it wins the award because its base is high, already on a high hillside anyway.

Measured from the core of the Earth, Mount Chimborazo in Ecuador is the highest in the world at more than 2,072 meters (6,800 feet) above Everest. As the Earth bulges in the middle, the mountains along the Equator are far from the core.

Measured from the foot of the mountain to the summit, Mauna Kea in Hawaii is the highest. However, most of it is under the sea.