A dusty film of pollution is muting the reflective whiteness of Greenland’s pristine icecap and making it vulnerable to accelerated melting rates.
Greenland is getting darker. Climatology’s great white hope, the biggest block of ice in the northern hemisphere, is losing its reflectivity.
According to new research, the island’s dusty snows are absorbing ever more solar radiation, which is likely to accelerate the rate at which the icecap melts.
The Greenland icecap covers 1.7 million square kilometres and contains enough ice to raise sea levels by seven metres. Right now, the rate of melting is on the increase, and meltwater flowing off the icecap could be raising sea levels by 0.6mm a year.
A powerful contributing factor, scientists report in The Cryosphere journal, could be that the ice has darkened over the last two decades. By 2100, the albedo – the climatologists’ term for the reflectivity of rock, sand, water or ice – could have fallen by 10%.
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