New Thinking On When The Arctic Froze

Courtesy: NASA

From Live Science:

The Arctic may be a frigid, ice-covered area today, but it hasn't always been quite so cold.

Scientists have long wondered when the Arctic first transitioned to its ice-covered state; a new study suggests this could have happened millions of years earlier than was previously thought.

The standard view of the formation of the huge ice sheets that cover Earth's poles was that continental-scale glaciation of Antarctica occurred about 34 million years ago, while the Arctic wasn't covered by ice until some 31 million years later — much more recently geologically-speaking.

But the new findings hint that Arctic ice may not have taken quite as long to form, with evidence placing its formation closer in time to that of Antarctic ice. Now researchers say Arctic ice could have formed about 23 million years ago.

A group of U.S. and U.K. climatologists, led by Robert DeConto of the University of Massachusetts, used a model to test the idea that Arctic ice formed much earlier than thought. Their work was funded by the U.S. National Science Foundation, and the results are detailed in the Oct. 2 issue of the journal Nature.

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