Mummified forest offers glimpse of a warmer Arctic

Randy Boswell
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 the ecological ice box it’s been for millennia.

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 million 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.

“Mummified forests aren’t so uncommon, but what makes this one unique is that it’s so far north. 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.”

The discovery was made last year after a ranger in Quttinirpaaq National Park mentioned to Barker — who was conducting research on Ellesmere Island — that some wood was seen sticking out of wet ground beside a melting glacier.

Barker made note of the site and returned this past summer to conduct a full investigation.

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, Ellesmere is mainly a home for muskoxen and one of the world’s most inhospitable places for humans, though its bone-chilling temperatures have been warming and its ancient coastal ice shelves collapsing in recent years.

Yet when the forest was flourishing in the early Neogene period, the northern part of the future Canada was a much different environment.

“I doubt that animal tissue would be preserved,” Barker said Thursday. He added that while “bones might be preserved in a mummified state,” the key finding so far is the well-kept wood and leaves that promise to give scientists a high-resolution picture of an ecosystem in crisis.

The U.S. scientists are hoping that the site, described in detail for the first time Dec. 16 at a geology conference in San Francisco, will yield other preserved vegetation and even mummified animal species, such as insects, that can be probed for their DNA.

“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.”

Although preserved for millions of years beneath the Arctic ice, the recent exposure of the wood means it will finally begin decomposing, sending carbon emissions into the atmosphere.

Forest co-discoverer David Elliot, professor emeritus of earth sciences at Ohio State, said the mummified forest on Ellesmere Island doesn’t pose an immediate threat to the environment, though.

“I want to be clear — the carbon contained in the small deposit we’ve been studying is trivial compared to what you produce when you drive your car,” he said.

“But if you look at this find in the context of the whole Arctic, then that is a different issue. I would expect other isolated deposits to be exposed as the ice melts, and all that biomass is eventually going to return to carbon dioxide if it’s exposed to the air.”

Elliot added: “It’s a big country, and unless people decide to walk all across the Canadian Arctic, we won’t know how many deposits are out there.”

Researchers have discovered the remains of a mummified forest that lived on Ellesmere Island two to eight million years ago, when the Arctic was cooling. Remnants of a similar fossil forest, dating from an earlier period, can be on Axel Heiberg island. (PHOTO BY JOEL BARKER/OHIO STATE UNIVERSITY)