A glacier at Mount Everest’s top that took millennia to build has receded drastically in the last three decades owing to climate change, according to a new research.
According to research headed by the University of Maine and published this week in Nature, the South Col formation may have already lost roughly 55 meters (180 feet) in thickness in the previous 25 years.
According to the study, carbon dating revealed that the top layer of ice was roughly 2,000 years old, implying that the glacier was shrinking more than 80 times quicker than it took to form.
The study, published in the Nature Portfolio Journal Climate and Atmospheric Research, discovered that Mount Everest’s South Col Glacier, which climbers travel on their way to the top, may have lost half its mass due to rising temperatures in the region since the 1990s. It may be extinct by the middle of the century.
The results are the outcome of the 2019 National Geographic and Rolex Perpetual Planet Everest Expedition, which included 34 foreign and Nepali scientists, several Sherpas, and a variety of logistical hurdles.
At such rate, South Col was “probably going to disappear within very few decades” according to head scientist Paul Mayewski.
The South Col Glacier, according to mountaineer Ryan Waters, who has summited Everest six times but was not part in this study, provides a spectacular sight for climbers nearing the end of their trip. “You quickly take in the massive snows and ice of Everest’s glacier pouring down above the high camp,” he continues.
It was one of the expedition’s focal points since mountain glaciers throughout the world are rapidly receding due to climate change. However, according to Mayewski, a glaciologist and the head of the University of Maine’s Climate Change Institute, there is little knowledge regarding glaciers at high heights.
“And one of the questions was: Obviously, it gets much colder up there.” So, are the glaciers on Everest, even those as high as 8,000 meters (26,250 ft), where South Col is located, receding?”
The extraction of a cylindrical chunk of ice from the glacier at a height more than 1,000 meters (3,200 feet) higher than the previous highest ice core ever obtained was a critical component of the investigation. To do so, current drilling equipment had to be modified to be as light as possible so that it could be carried up the mountain by hand and operated in the thin air. Although the crew tested the equipment in extreme cold temperatures in Maine, Iceland, and the Himalayas, there was no assurance it would operate when it was most required.
Potocki and the crew, on the other hand, were taken aback by the results. Radiocarbon dating found that the ice at the surface was about 2,000 years old when the 10-meter (33-foot) ice core was investigated. In other words, whatever ice that had accumulated on the glacier during the previous two millennia had just vanished. The core contains layers of yearly ice growth, similar to tree rings, and the scientists concluded that, assuming the rate of ice deposition has stayed constant throughout time, about 55 meters (180 feet) of ice has been lost by calculating their thickness.
According to the researchers, ice loss is likely hastened by a process known as sublimation, in which snow and ice melt without passing through a liquid-water phase. Sublimation is frequent in climates that are cold and dry, especially at high elevations, but also have a lot of sunshine and strong winds—all of which the south face of Everest meets. And it’s compounded on South Col Glacier, according to Potocki, by a near-complete lack of snow cover on the glacier’s surface.