Antarctic permafrost, which had been weathering global warming far better than areas around the North Pole, is starting to give way. Scientists have recorded some of it melting at rates that are nearly comparable to those in the Arctic.
Scientists used time-lapse photography and LiDAR to track the retreat of an Antarctic ice cliff over a little more than a decade. The permafrost that made up the cliff was found to be disappearing nearly 10 times more quickly than was the case during recent geological history.
Cliff-face measurements of the buried ice in the four-mile-long Garwood Valley revealed melt rates that shifted from a creeping annual rate of about 40,000 cubic feet per year over six millenniums, to more than 402,000 cubic feet last year alone.
The scientists think the melt was caused by growing amounts of dark debris on the surface of the ice and snow that absorbed the sun’s rays.
If temperatures in the valley eventually start to rise, as expected with global warming, then things could get really watery.
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