New Research Shows Greenland Ice Sheet 'Dark Zone' Melting Faster Than We Thought

Friday, 13 April 2018 - 11:45AM
Friday, 13 April 2018 - 11:45AM
New Research Shows Greenland Ice Sheet 'Dark Zone' Melting Faster Than We Thought
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Image credit: YouTube

Clearly visible from satellite imagery, there is a strip of Greenland's ice sheet that is getting darker and darker and melting faster and faster. New drone research has confirmed what researchers previously thought was creating the "Dark Zone" and has also given scientists a better idea of just how bad things are.



The Dark Zone is located toward the south-west of Greenland's ice sheet and stretches 248 miles long and 61 miles wide. New research conducted by the Norwegian Centre for Arctic Gas Hydrate, Environment and Climate (CAGE) found that the darkening of the ice is not from a Fern Gully-like oil demon taking over—it's actually "mineral and microbial debris" on the surface of the sheet, a suggestion first made by Dave Chandler of the Bristol Glaciology Centre and his team of field researchers in 2014 .



"What we show is that the Dark Zone is covered in a finely distributed layer of dust, and black carbon, which provide nutrition for dark-colored algae. These are the main cause of the darkening," said co-author Alun Hubbard. 

 

The Dark Zone is also in what is known as the ablation zone, which is an area that is melting faster than other spots on the ice sheet. The darker the zone gets, the more sun it absorbs and the faster it melts.

 

"The fact that a large portion of the western flank of the Greenland ice sheet has become dark means that the melt is up to five times as much as if it was a brilliant snow surface," Hubbard explains. "The algae need nutrients and food, essentially dust, organic carbon, and water. In summer, these are plentiful and the algal bloom takes off. Because algae are dark in color—they reinforce the dark zone. Thereby you get a positive feedback effect where the ice sheet absorbs even more solar radiation producing yet more melt."



That may sound like a Greenland problem, but some it may be a problem for the entire planet. The melting of Greenland is causing sea levels to rise as much as 3 millimeters every year.

 

If it ALL melts, experts say that it would add up to 25 feet of water to the world, which would not be great for anyone.

 

Hubbard and his team say that further research is needed to understand the algae growth and the role that everything plays in melting and runoff, so maybe don't panic just yet— or do, after all, conspiracy theorists think the world is ending April 23—but definitely be a little concerned.

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