Greenland and the Disappearing Ice-Cap

Greenland, home to 57,000 people and a giant ice-cap. At least, that's the case at the moment. The problem is that the giant ice-cap is melting, and it's showing no sign of slowing down. In fact, the melt is speeding up, due largely to warmer summers and a substance called 'Cryoconite'.

Discovered by Arctic explorer Nils A. E. Nordenskiöld in 1870, Cryoconite gives the ice a brown or black colour. It comes to Greenland in the form of airborne particles. Some of these particles come from as far away the deserts of Central Asia, and some are bits of soot from engines and coal-fired power stations, reinforcing the Human dimension of this process.

It is the dark colour of Cryoconite which is the problem. As it blackens the ice, it no longer reflects sunlight back into space, instead absorbing more heat causing greater amounts of ice to melt. With the warmer summers in recent years, more Cryoconite from deeper leves of the ice-cap have come to the surface, causing further darkening of the ice. Coupled with the increase of man-made particles, this has produced an accelerating cycle of ice-melt.

This increase is causing some of the vast melt-water lakes in Greenland to drain through massive vertical shafts that are being called 'Moulins'. In Mark Jenkins' article in the National Geographic magazine, he says that:

"In 2006 a team led by glaciologists from Woods Hole Oceanographic Institution and the University of Washington documented the draining of a two-square-mile supraglacial lake: More than 11 billion gallons of water disappeared into a moulin in 84 minutes, flowing faster than Niagara Falls."

He goes on to say that:

"Scientists have dumped yellow rubber duckies, sensored spheres, and huge quantities of dye into moulins, hoping to track their journeys and discover where along Greenland's coast the moulins empty. Some of the spheres and dye have been spotted; all the duckies disappeared."

This is some thing which scientists will be monitoring over the next few years, as a loss of the Greenland ice-cap could cause a massive rise in sea-levels. Do have a look at this interactive from the same article quoted above, as well as its photogallery.