Mummified forest provides climate change clues
LOS ANGELES – On a remote island in the Canadian Arctic where no trees now grow, a newly unearthed mummified forest is giving researchers a peek into how plants reacted to ancient climate change.
That knowledge will be key as scientists begin to tease out the impacts of global warming in the Arctic.
The ancient forest found on Ellesmere Island, which lies north of the Arctic Circle in Canada, contained dried out birch, larch, spruce and pine trees. Research scientist Joel Barker of Ohio State University discovered it by chance while camping in 2009.
"At one point I crested a small ridge and the cliff face below me was just riddled with wood," he recalled.
Armed with a research grant, Barker returned this past summer to explore the site, which was buried by an avalanche 2 million to 8 million years ago. Melting snow recently exposed the preserved remains of tree trunks, leaves and needles.
About a dozen such frozen forests exist in the Canadian Arctic, but the newest site is farthest north.
The forest existed during a time when the Arctic climate shifted from being warmer than it is today to its current frigid state. Judging by the lack of diverse wood species and the trees' small leaves, the team suspected that plants at the site struggled to survive the rapid change from deciduous forest to evergreen.
"This community was just hanging on," said Barker, who presented his findings Thursday at the American Geophysical Union meeting in San Francisco.
The next step is to examine tree rings to better understand how past climate conditions stressed plant life and how the Arctic tundra ecosystem will respond to global warming.
Since 1970, temperatures have climbed more than 4.5 degrees in much of the Arctic, much faster than the global average.
Barker also plans to conduct DNA tests on the remains.
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Online:
American Geophysical Union: http://www.agu.org
Ohio State University: http://www.osu.edu
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