In a record-setting examine, a staff of scientists scaled the world’s highest peak to observe the mountain’s highest-altitude glacier — the South Col Glacier, standing practically 26,000 ft (8,000 meters) above sea degree — for indicators of climate-related ice loss. After putting in the 2 highest climate stations on Earth and accumulating the world’s highest ice core from the glacier, the staff discovered that South Col is shedding ice roughly 80 occasions quicker than it took for the ice to build up on the glacier’s floor, they reported Feb. 3 within the journal npj Local weather and Atmospheric Science.
The staff’s core evaluation confirmed that ice that took 2,000 years to type on the glacier has fully melted away because the Nineteen Nineties, and that the glacier is at present shedding a number of many years value of ice accumulation yearly.
“[This study] solutions one of many large questions posed by our [expedition] — whether or not the best glaciers on the planet are impacted by human-source local weather change,” examine co-author Paul Mayewski, a glaciologist on the College of Maine and director of the College’s Local weather Change Institute, mentioned in an announcement. “The reply is a convincing sure, and really considerably because the late Nineteen Nineties.”
The glacier’s fast decline might have critical impacts on the mountain, and people who reside close to it. The soften might lead to extra avalanches on Everest, or expose extra bedrock that makes the terrain extra treacherous for climbers, the examine authors discovered.
‘Destined for fast retreat’
On a current expedition, 10 researchers climbed to the bottom of South Col Glacier and put in two climate detection stations — one at 27,600 ft (8,430 m) and the opposite at 26,200 ft (7,945 m) above sea degree. The staff additionally drilled a 32-foot-long (10 m) ice core from the glacier, which might reveal how the glacier ice’s thickness has modified over time.
With this knowledge in hand, the staff ran laptop fashions to simulate the glacier’s progress and retreat over 1000’s of years. The staff concluded that South Col Glacier has misplaced greater than 180 ft (54 m) of ice thickness within the final 25 years. Whereas the results of wind and adjustments in humidity might have contributed considerably to this ice loss, human-induced local weather change is the overwhelming trigger, the researchers mentioned.
The truth is, the staff discovered that South Col Glacier might have begun thinning from local weather change as early because the Nineteen Fifties. Nevertheless, by the Nineteen Nineties, the soften price accelerated considerably when the glacier’s snowpack (the outer layers of snow that accumulate over time) lastly disappeared, exposing the glacier’s uncooked ice to the solar’s radiation. Now, lacking its protect of white ice to replicate the solar’s rays, South Col Glacier appears “destined for fast retreat,” the researchers wrote of their examine.
In the end, whereas South Col is only one glacier amongst many within the Himalayas, its place on the high of the world exhibits that no ice mass is protected from local weather change. If the identical melting traits happen in different glaciers throughout the Himalayas, then the glacier-stored water that greater than 1 billion folks depend upon for ingesting water and irrigation might begin to deplete considerably, the authors mentioned.
Future analysis should deal with how broadly these melting traits apply to different glaciers on the high of the world, the researchers concluded.
Initially revealed on Reside Science.