North America's tallest mountain could start expelling years' worth of human faeces due to global warming.
USA Today reports Denali could be home to around 66 tonnes of human waste from climbers who left it frozen for years.
But a process that has been speeding up due to climate change means that this waste may start to melt out of the glacier "as soon as this summer".
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National Park Service glaciologist Michael Loso conducted experiments that showed discarded excrement left in snow pits or thrown into deep crevasses in the mountain eventually resurfaced downstream, despite people thinking for years it would be ground up by the ice.
"The waste will emerge at the surface not very different from when it was buried... It will be smushed and have been frozen and be really wet," he told USA Today.
"We expect it to still smell bad and look bad."
This was true of all glaciers, which are extremely slow-moving rivers of ice.
The park service has introduced a new rule that any excrement below 14,000 feet must be brought back down the mountain, in an attempt to stop this resurfacing process from occurring.
"Climbers and particularly guide services are really embracing the new policy and are even exceeding it. It has become kind of an informal badge of merit to carry off all your waste," says Loso.
Recent news reports say the melting ice on Mt Everest is uncovering the dead bodies of some of those who never made it to the top of the world's tallest peak.