Thawing permafrost soils in the rapidly warming Arctic will emit as much greenhouse gas as large industrial nations by the end of this century, according to a University of Alberta researcher involved in an international study that stresses to policy makers that it's not too late to act to stabilize the climate and avoid exceeding temperature targets.
"If we avoid the worst-case scenarios of warming, our assessment shows that emissions from thawing permafrost are still going to be equivalent to somewhere between 60 and 80 billion tonnes of carbon over the next 80 years, which is a rate similar to current-day carbon dioxide emissions from Western Europe," says scientist David Olefeldt of the Faculty of Agricultural, Life & Environmental Sciences, the lone Canadian co-author on the research.
The team, Led by Northern Arizona University and the international Permafrost Carbon Network, estimates that under a low warming scenario -; one that could be achieved if the global community limited warming to 2 C -; permafrost would release 55 billion tonnes of carbon by the end of the century in the form of carbon dioxide and methane.
If nothing is done to mitigate climate warming, the study estimates the Arctic could release nearly five times that amount, which is twice the amount of carbon-dioxide equivalent emissions the United States has released since its industrial rise to power began 150 years ago.
"It's not something that's going to cause runaway climate change, but it definitely adds an accelerant to climate change and is an important component of the future greenhouse gas budget for the world," he explains.
"The more we are able to restrain human emissions and thereby avoid the worst-case scenarios of warming, the more carbon is going to stay in the ground in the Arctic."