Well, if you’ve been planning a summit bid for Everest, and have trained so much that you’ve taken each centimeter of altitude into account, you’re gonna need to adjust your metrics a bit.
Nepal and China have finally announced the new, official measurement, of the world’s highest point—29,031.69 feet, or 8,848.86 meters. That’s 86 centimeters higher than the previous official measurement, recorded in the early 1950s.
It took a couple years to arrive at this point, from envisioning a new method for recording Everest’s height, to the big reveal, as well as a lot of work. It even took one toe, after a surveyor from Nepal lost one to frostbite when deploying a radar unit on the summit last year.
“It will be difficult to improve on the new number,” Roger Bilham, a geologist at the University of Colorado, told the Washington Post. Nepal’s new measurements are “remarkable for their density.”
Measuring Everest required a blend of old and new techniques.
Surveying and trigonometry, yes, that was done but it’s kinda the easy part.
Figuring out where sea level technically is, below Everest, is extraordinarily difficult.
That was done partially with the aid of a gravimeter, a device that can measure gravity at specific locations, data that can be used to accurately map where sea level would lie at Everest’s base. Nepal deployed a gravimeter in hundreds of locations around the country, which, in effect, helped walk an imaginary sea level line from the coast to the mountain.
Imagine Everest lifted from the Earth’s crust, and placed on top of the sea in the Bay of Bengal (typically, where sea level is calculated when estimating Everest’s height). That’s essentially what the gravimeters data can do.
Most of that was done by Nepal’s team. The country spent more than $1.3 million on the survey, in an effort to establish a measurement on their own, free from Chinese influence. Chinese surveyors performed their own measurements, based on satellite data and data collected from a survey back in 2005.
China’s measurement was close enough to Nepal’s for the two countries to agree on the new figure.
While the mountain is pushed upwards by millimeters each year, this new measurement is a result of better instruments and data, not that the mountain has actually grown more than two feet in 70 years.
Photo: Chen Zhang/Unsplash