Sea ice north of Greenland - some of the oldest and thickest in the Arctic - has broken up for the second time this year, a phenomenon never seen before.

Satellite images show ice melting around the coast of the island closest to the North Pole, opening up waters that are usually frozen, even in summer.

One meteorologist said the loss of ice was "scary".

Rasmus Tage Tonboe, a sea ice expert from the Danish Meteorological Society, told Sky News: "Right now, the sea ice in the Arctic is near its annual minimum, it is melting.

Image: An image showing the extent of sea ice around Greenland on 22 August. Pic: Seaice.dk

"But this year sea ice north of Greenland, which is normally the thickest and most robust, has retreated from the coast in quite broad band of open water.


"The first event happened in February when the temperatures were very high and the water was blowing away from the coast and created open water areas.

"We have not seen open water of this extent since we began satellite recording of this 40 years ago."

He added that the ice froze back over after the February defrost, but was much thinner than it had been.

Image: An image describing conditions on sea ice around Norway. Pic: METNO

Mr Tonboe said: "This thick and robust ice is important for the climate, and for the feedback mechanisms at play here and also for the polar bears.

"We need this thick ice all year."

Mr Tonboe said although northern Europe had benefited from a very warm summer, there was not a direct link between the weather and what is happening in the Arctic.

"It is not related to the mean temperatures which have been very very warm.

"It is part of the overall climate trend, the temperatures in the Arctic rising but this summer was not a record there."

So the open water / low concentration patch North for Greenland is still there (and slowly moving westward). Nice and scary. From https://t.co/jPx1JmNayA https://t.co/hGstLYafcW — Thomas Lavergne (@lavergnetho) August 13, 2018

The sea ice off the north coast of Greenland had previously been described as the "last ice" as it had been assumed this would be the final place to melt entirely. Scientists may have to revise this theory.

Thomas Lavergne, a scientist at Norway's meteorological institute METNO, tweeted the images, saying they were "nice and scary".

He told the Guardian: "I cannot tell how long this open water patch will remain open, but even if it closes in few days from now, the harm will be done: the thick old sea ice will have been pushed away from the coast, to an area where it will melt more easily."

It is typical of a phenomenon that is occurring across the Arctic Circle.

Here is a closer look at the sea ice pushing north of Greenland via Sentinel-1 satellite. Interestingly, this is the 2nd time this has happened this year. This ice is probably quite a bit thinner than usual and responsive to drift dynamics.



[Imagery from https://t.co/8K8XMCaReA] pic.twitter.com/9TuGWOb4sX — Zack Labe (@ZLabe) August 8, 2018

Norway's ice service said Svalbard's sea ice area for 21 August was 111,968 sq km, adding "this is 115,969 sq km below the 1981-2010 average".

They said the current area was the lowest on record.

Cambridge University physicist Professor Peter Wadhams warned the melting ice could severely impact the polar bear population.

He told the Independent: "The north coast of Greenland, with its very steep cliffs, is a denning area for polar bears.

Image: Sea ice spotted from NASA's Operation IceBridge research aircraft off Greenland

"They dig holes in the snow and come out in the spring and go hunting.

"But if the pack ice has moved offshore they come out of hibernation and are left without an area to hunt.

"They can't swim very far.

"If this becomes a permanent feature with ice away from the coast, polar bears won't have any ice to hunt on. You would lose the polar bear habitat."

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