A team of researchers from Aberystwyth and Leeds universities are making final preparations for a trip to Mount Everest in Nepal next month to explore why the ice on one of the mountain’s most iconic glaciers is so close to the melting point.

The expedition will take them into the Western Cwm, where they believe that intense radiation from the sun is melting the snow even when air temperatures are below freezing.

As the meltwater refreezes it can warm the snow by several degrees, creating glacier ice that is much closer to the melting point than has previously been realised.

If they are right, this is a process that may also be happening on other glaciers across the Himalaya, whose meltwater sustains many millions of people below in countries including Nepal, Bhutan, India, Pakistan and Afghanistan.

The researchers will be operating at over six kilometres above sea level and half a kilometre above Everest Base Camp, where they will drill into the glacier and use the boreholes to record ice temperatures.

They will have to negotiate the Khumbu Icefall - regarded as one of the most demanding sections of the South Col route to Everest's summit - while their equipment is transported by helicopter.

Once settled on the glacier, the team will be camping on ice with nighttime temperatures dipping below -10 °C.

The Everest researchers hope their work will give them a new understanding of processes and changes that are relevant for all glaciers in similar settings world-wide and indicate the extent to which other glaciers within the Himalayas may also contain unexpectedly warm ice.

Professor Bryn Hubbard from Aberystwyth University’s Department of Geography and Earth Sciences said: “It may surprise many that snow could be melting at sub-freezing air temperatures high up within Everest’s Western Cwm, but the possibility needs to be investigated and measured.

“These temperature measurements will improve computer models that are used to predict future changes in glacier extent and water supply – particularly important in this heavily-populated and water-stressed region.

“For this project, we will build on Aberystwyth University’s expertise in borehole drilling and sensor development to record ice temperatures deeper into the ice and at higher elevations than ever before attempted.

“Since, at these elevations, we can no longer rely on power from combustion motors, we plan to use energy from solar, battery and propane to drill boreholes some tens of metres into the ice.

“We also plan to use satellites to send real-time data back from the Western Cwm directly to our computers in the UK, reducing the number of future trips required to download data and service the equipment.”

The new project follows previous findings by the researchers which showed that the temperature of the ice in the lower parts of Khumbu Glacier is warmer than would be expected given the local air temperature.

The project is funded by the Natural Environment Research Council and is a collaboration between academics from the University of Leeds, Aberystwyth University, the University of Bergen (Norway) and Uppsala University (Sweden).