Ice temperatures inside the world’s highest glacier on the slopes of Mount Everest are hotter than anticipated and particularly vulnerable to future climate change. The outcomes suggest that high-elevation Himalayan glaciers are vulnerable to even minor atmospheric warming and will be especially sensitive to future climate warming.
In 2017, the EverDrill project research team driven by Dr. Duncan Quincey from the University of Leeds became the first to effectively bore into Khumbu Glacier in Nepal and record temperatures far beneath the surface layer.
In a new study, scientists revealed a minimum ice temperature of only −3.3 °C, with even the coldest ice being a full 2 °C warmer than the mean annual air temperature.
Study co-author Dr. Quincey from the School of Geography at Leeds said, “The temperature range we measured from drill sites across the Khumbu Glacier was warmer than we expected –and hoped – to find.”
“Internal temperature has a significant impact on the complex dynamics of a glacier, including how it flows, how water drains through it, and the volume of meltwater runoff – which makes up a crucial part of the water supply for millions of people in the Hindu Kush-Himalaya region.”
Study lead author Katie Miles from Aberystwyth University explained that the Khumbu Glacier’s vulnerability may have serious consequences for the lifespan and amount of meltwater runoff in the coming decades, and it will be important to determine if other glaciers in the region have similar internal characteristics to Khumbu.
For the study, scientists traveled to Khumbu Glacier, Nepal in 2017 and 2018. They used a specially adapted car wash unit that produced a pressurized jet of hot water to drill boreholes as far as 190 meters into the glacial ice. Strings of temperature sensors were installed into these boreholes and left to collect data for several months.
Dr Quincey said: “Until now, the limited amount of data collected from glaciers in this region has made it difficult to predict how environmental change could affect the glaciers’ internal dynamics.”
“Insights from the EverDrill project can aid scientists in forecasting the impact of global warming and how long the region can rely on meltwater to feed downstream water supply.”
The team includes Dr. Quincy, Dr. Evan Miles, now based at the Swiss Federal Research Institute WSL, Switzerland, Professor Bryn Hubbard and Katie Miles, both from Aberystwyth University, and scientists from Kathmandu and Sheffield Universities.
The study is published in the journal Scientific Reports.