Everest’s highest glacier rapidly losing ice accumulated for millenniums

Data from a new paper published recently in the Nature Portfolio Journal Climate and Atmospheric Science, has identified Mount Everest’s highest glacier is rapidly losing several centureis of ice accumulation annually.

The earth’s warmer climate is causing melting and sublimation where the exposed ice, which is darker, absorbs more sunshine which in turn accelerates the melt rate.  

The report has pointed out that the it has jeopardized both climbers and those who depend on the glacier for drinking water and irrigation. It revealed that the South Col Glacier, which sits around 7,906m (25,938 ft) above sea level, has lost as much as 55m of thickness in the last 25 years. Further it said that the Everest glacier is melting over 80 times faster than the 2,000 years it took to form the ice.

A team of scientists and climbers, including six from the University of Maine, visited the glacier in 2019 and extracted samples from a 10-metre-long (around 32 feet) ice core. They also installed the world's two highest automatic weather stations to collect data and answer a question whether the earth's most out-of-reach glaciers were impacted by human-linked climate change.

A team of scientists and climbers, including six from the University of Maine, visited the glacier in 2019 and collected samples from a 10-meter-long (around 32 feet) ice core.

The research showed that once the glacier’s ice became exposed, it lost around 55 meters (180 feet) of ice in 25 years.

The researchers note that the glacier has transformed from consisting of snowpack into predominantly ice, and that change could have started as early as the 1950s. But the ice loss has been most intense since the late 1990s.

This transformation to ice means the glacier can no longer reflect radiation from the sun, making its melt more rapid. Model simulations show that because of the extreme exposure to solar radiation, melting or vaporization in this region can speed up by a factor of more than 20, once snow cover transforms to ice. A drop in relative humidity levels and stronger winds are also factors.

In addition to all the impacts on those who depend on water from glaciers, the current rate of melt would also make expeditions on Mount Everest more challenging, as snow and ice cover thin further over coming decades.

They also installed the world's two highest automatic weather stations to collect data and answer a question: Are the Earth's most out-of-reach glaciers impacted by human-linked climate change?

"The answer is a resounding yes, and very significantly since the late 1990s," said Paul Mayewski, the expedition leader and the director of the Climate Change Institute at the University of Maine.

The researchers said that the findings not only confirmed that human-sourced climate change reached the highest points on Earth, but that is it was also disrupting the critical balance that snow-covered surfaces provide.

"It's a complete change from what has been experienced in that area, throughout probably all of the period of occupation by humans in the mountains," Mayewski said. "And it's happened very fast."

The 2019 expedition also set three Guinness World Records: The highest altitude ice core taken at 8,020 meters, the highest altitude microplastic found on land, which were likely from clothing or tents, found at 8,440 meters; and the highest altitude weather station on land, installed at "Balcony," a ridge sitting 8,430 meters above sea level.

The station is the first installed in what is known as the "death zone" for its dangerous hiking conditions -- it's the zone above 8,000 meters where there's not enough enough oxygen to sustain life beyond short periods of time.