As frozen soil thaws, prehistoric bacteria are coming back to life and converting woolly mammoth remains into greenhouse gases, which could cause global warming to spiral out of control
Scientists have been warning us about the potential catastrophe of melting Arctic ice for decades. Now they’ve discovered a new threat underneath the ice – thawing soil.
A layer of frozen soil — or “permafrost” — a thousand feet thick covers about a quarter of the Northern Hemisphere of our planet.
Trapped in that frozen soil is twice as much carbon as is currently in our atmosphere. As the ice melts and the soil warms up, scientists worry that carbon could be released, furthering global warming, and in turn, further thawing the soil.
Their fears are based on experiments that demonstrate what happens when permafrost thaws.
A few years ago, Dr. Thomas Douglas, a geochemist at the U.S. Army Corps of Engineers, and his colleagues, drilled a few chunks of permafrost, the size of soda cans, from an underground tunnel in Fairbanks, Alaska.
“They took the ice back to the lab and let it slowly come up to room temperature,” reports NPR. “Then they looked for signs of life. A few days later, something started growing — slowly at first, but then like gangbusters.”
They were prehistoric bacteria, frozen for 25,000 years, and “once they warmed up, they were hungry,” writes journalist Michaeleen Doucleff, who took a tour of the tunnel.
Along with the bacteria, the permafrost is packed with preserved green grass, trees, woolly mammoths, woolly rhinoceroses and “just about every creature that lived on the tundra over the past 100,000 years,” Doucleff writes.
As the bacteria came back to life, they started decomposing these frozen remains and releasing the carbon and methane they contained.
Last year, scientists started seeing signs of what happened in the lab on a larger scale in northern Alaska, where the temperature at some permafrost sites has risen by more than 4 degrees Fahrenheit since the 1980s, according to the National Oceanic and Atmospheric Administration.
“We have evidence that Alaska has changed from being a net absorber of carbon dioxide out of the atmosphere to a net exporter of the gas back to the atmosphere,” NASA chemist Charles Miller told NPR.
If the soil were to get warm enough for frozen bacteria to begin waking up across the Arctic, Canada, Greenland and Russia, we’d be in for a wild ride, Douglas says.
There is more carbon trapped in that permafrost than all the carbon humans have spewed into the atmosphere since the Industrial Revolution, he says.
Once carbon begins to percolate up through the thawing soil, it could form a feedback loop “over which we would have zero control,” Miller added.