Greenland's varied past



Core-drillers have found evidence that Greenland has on a couple of occasions been much hotter in the geologically recent past, despite the absence of coal burning power stations and 4WDs back then. More interesting, however is that it took a 10 degree warming to melt only part of the Greenland icecap and that a 5 degree warming did not melt it at all. Warmist theories that we are already near a tipping point and runaway warming are therefore falsified by actual evidence -- given that the warming for the entire 20th century was less than one degree

Armies of insects once crawled through lush forests in a region of Greenland now covered by more than 2,000m of ice. DNA extracted from ice cores shows that moths and butterflies were living in forests of spruce and pine in the area between 450,000 and 800,000 years ago.

Researchers writing in Science magazine say the specimens could represent the oldest pure DNA samples ever obtained.

The ice cores also suggest that the ice sheet is more resistant to warming than previously thought, the scientists say.

"We have shown for the first time that southern Greenland, which is currently hidden under more than 2km of ice, was once very different to the Greenland we see today," said Professor Eske Willerslev from the University of Copenhagen, Denmark, and one of the authors of the paper.

"What we've learned is that this part of the world was significantly warmer than most people thought," added Professor Martin Sharp from the University of Alberta, Canada, and a co-author of the Science paper.

The ancient boreal forests were thought to cover southern Greenland during a period of increased global temperatures, known as an interglacial. Temperatures at the time were probably between 10C in summer and -17C in winter.

When the temperatures dropped again 450,000 years ago, the forests and their inhabitants were covered by the advancing ice, effectively freezing them in time.

Studies suggest that even during the last interglacial (116,000-130,000 years ago), when temperatures were thought to be 5C warmer than today, the ice persevered, keeping the delicate samples entombed and free from contamination and decay. At the time the ice is estimated to have been between 1,000 and 1,500m thick.

"If our data is correct, then this means that the southern Greenland ice cap is more stable than previously thought," said Professor Willerslev. "This may have implications for how the ice sheets respond to global warming."

Comparisons with modern species show that the area was populated by diverse forests made up of alders, spruce, pine and members of the yew family.

Living in the trees and on the forest floor was a wide variety of life including beetles, flies, spiders, butterflies and moths.

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