Thursday, December 16, 2010

Preserved Arctic forest offers climate clues

2-million-year-old 'mummified' forest discovered in Arctic
Postmedia News: A research team probing a melting glacier near Canada's northernmost point of land has discovered a 'mummified' forest that's at least two million years old, with 'perfectly preserved' tree trunks, branches and leaves from a time when the Arctic was transforming from a temperate environment into [an] ecological icebox...

The present-day thaw at the north end of Ellesmere Island -- another sign of the widespread warming now taking hold of Canada's polar frontier -- has served up intact spruce and birch trees believed to have been buried in a landslide during the Neogene period of Earth history between two and eight million years ago.

The U.S. scientists studying the ancient forest, who say the liberation of the long-frozen relics will offer a unique window on a lost world, are also warning that pent-up carbon released from such sites across the Arctic could worsen the modern-day climate change being driven by human activity...

'When the climate began to cool 11 million years ago, these plants would have been the first to feel the effects,' said Joel Barker, an Ohio State University earth scientist, in a summary of the findings. 'And because the trees' organic material is preserved, we can get a high-resolution view of how quickly the climate changed and how the plants responded to that change.'...

His research team unearthed a number of birch and spruce trees, some that had lived as long as 75 years when they were rooted in the once-rich soil of Ellesmere Island millions of years ago. Today, top-of-the world Ellesmere is mainly a home for muskoxen and one of the world's most inhospitable places for humans...

'These trees lived at a particularly rough time in the Arctic,' Barker said. 'Ellesmere Island was quickly changing from a warm deciduous forest environment to an evergreen environment, on its way to the barren scrub we see today. The trees would have had to endure half of the year in darkness and in a cooling climate. That's why the growth rings show that they grew so little, and so slowly.'
Source of images here.