Date of earliest Arctic sea ice pushed back 1.25 million years

Fossils of marine algae reveal that Arctic sea ice formed 47.5 million years ago.  Researchers tooks samples from a submarine ridge about 250 kilometers (150 miles) from the North Pole.  In sediments deposited 47.5 million years ago, they found fossils of algae whose modern cousins live in sea ice, which pushes back the earliest known date of Arctic sea ice by 1.25 million years.  The remains of the microorganisms (from the genus Synedropsis) made up as much as 61% of the fossils in the sediments.  The findings help to provide new details about the pace of global warming that was occurring at that time.

The report can be found at http://74.125.113.132/search?q=cache:0bh5D4xN2ncJ:www.iodp.org/index.php%3Foption%3Dcom_docman%26task%3Ddoc_download%26gid%3D2736+Stickley,+C.E.,+et+al.+2009.+Evidence+of+middle+Eocene+Arctic+sea+ice+from+diatoms+and+ice-rafted+debris.+Nature+460(Jul.+16):+376.&cd=2&hl=en&ct=clnk&gl=us.