Arctic tundra emits more carbon in winter than plants can absorb in summer: study

Phd candidate at Dalhousie University one of 75 co-authors of new paper in Nature Climate Change

The community of Apex, Nvt., is seen from Iqaluit on Friday, Aug. 2, 2019. THE CANADIAN PRESS/Sean Kilpatrick

The community of Apex, Nvt., is seen from Iqaluit on Friday, Aug. 2, 2019. THE CANADIAN PRESS/Sean Kilpatrick

Research has found Arctic soil has warmed to the point where it releases more carbon in winter than northern plants can absorb during the summer.

The finding means the extensive belt of tundra around the globe — a vast reserve of carbon that dwarfs what’s held in the atmosphere — is becoming a source of greenhouse gas emissions responsible for climate change.

“There’s a net loss,” said Dalhousie University’s Jocelyn Egan, one of 75 co-authors of a paper published in Nature Climate Change. “In a given year, more carbon is being lost than what is being taken in. It is happening already.”

The research by scientists in 12 countries and from dozens of institutions is the latest warning that northern natural systems that once reliably kept carbon out of the atmosphere are starting to release it.

Until now, little was known about winter emissions from permafrost and the soil above it. Even scientists assumed the microbial processes that release the gases came to a halt in the cold.

“Most people think in the winter, there’s no respiration, that the microbes eating the carbon that produce these emissions aren’t active, which isn’t actually the case,” Egan said.

The scientists placed carbon dioxide monitors along the ground at more than 100 sites around the circumpolar Arctic to see what was actually happening and took more than 1,000 measurements.

They found much more carbon was being released than previously thought. The results found carbon dioxide emissions of 1.7 billion tonnes a year are about twice as high as previous estimates.

Arctic plants are thought to take in just over one billion tonnes of the gas from the atmosphere every year during growing season. The net result is that Arctic soil around the globe is probably already releasing more than 600 million tonnes of CO2 annually.

Scientists previously thought carbon absorbed by tundra plants during the summer more or less made up for what was emitted in the winter as well as for what was released from melting permafrost during warm months.

That’s not what’s happening, said Egan.

“We’re seeing that the value emitted in the winter is larger than the net uptake for the growing season.”

What’s more, the pace of the emissions is likely to increase.

Under a business-as-usual scenario, emissions from northern soil would be likely to release 41 per cent more carbon by the end of the century.

But the Arctic is already warming at three times the pace of the rest of the globe. Even if significant mitigation efforts are made, those emissions will increase by 17 per cent, said the report.

Egan notes the research didn’t measure methane, a greenhouse gas about 30 times more potent than carbon dioxide that is also released from soil.

READ MORE: Oceans, glaciers at increasing risk, including Canada’s, climate report says

Bob Weber, The Canadian Press

Like us on Facebook and follow us on Twitter

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Alberta’s chief medical officer of health, Dr. Deena Hinshaw, confirmed eight additional virus-deaths Monday afternoon including one in central zone. (Photo by Chris Schwarz/Government of Alberta)
New record: Red Deer at 236 active COVID cases

One more death in central zone reported

Executive Director and Co-Founder of Rock Soup Craig Haavalsen is sleeping in a tent outside Rock Soup’s location until the Go Fund Me for Rock Soup raises $10,000. Shaela Dansereau/ Pipestone Flyer.
Putting normalcy into asking for help: New non-profit sets up in Wetaskiwin

Rock Soup non-profit is a new non-secular Food Bank putting down roots in Wetaskiwin.

file photo
County of Wetaskiwin Land Use Bylaw amendments approved

Ammendments approved by Wetaskiwin County Council at Nov. 24, 2020 Council meeting.

City of Wetaskiwin kicks off “Light Up Wetaskiwin” with light display at Wetaskiwin City Hall. Shaela Dansereau/ Pipestone Flyer.
Making spirits ‘bright’: Light Up Wetaskiwin contest kicks off

Up to $3000 in cash prizes available to the top 11 decorated homes and businesses.

Alberta had 1,571 active COVID-19 cases on Tuesday. THE CANADIAN PRESS
Alberta’s central zone now has 1,101 active COVID-19 cases

Provincial death toll has risen by nine

Idyllic winter scenes are part of the atmosphere of the holiday season, and are depicted in many seasonal movies. How much do you know about holiday movies? Put your knowledge to the test. (Pixabay.com)
QUIZ: Test your knowledge of holiday movies and television specials

The festive season is a time for relaxing and enjoying some seasonal favourites

Fossil finds at Mt. Stephen. (Photo: Sarah Fuller/Parks Canada)
Extreme hiking, time travel and science converge in the Burgess Shale

Climb high in the alpine and trace your family tree back millions of years – to our ocean ancestors

Deputy Prime Minister and Minister of Finance Chrystia Freeland listens to a question from a reporter on the phone during a news conference in Ottawa, Monday, Nov. 30, 2020. THE CANADIAN PRESS/Adrian Wyld
Spending too little worse than spending too much, Freeland says as Canada’s deficit tops $381B

‘The risk of providing too little support now outweighs that of providing too much’

Lawyer Devon Page, Ecojustice Canada’s executive director, pauses during a news conference in Vancouver on Wed., Sept. 26, 2012. The environmental law group has lost its bid to pause Alberta’s inquiry into where critics of its oil and gas industry get their funding. Ecojustice sought an injunction this summer to suspend the inquiry, headed by forensic accountant Steve Allan, until there is a decision on whether it’s legal. nbsp;THE CANADIAN PRESS/Darryl Dyck
Judge tosses application to pause Alberta inquiry into funding of oil and gas foes

Ecojustice sought an injunction in the summer to suspend the inquiry

Janelle Robinson owns and operates Spirit’s Respite Ranch near Stettler. The Ranch, just north of Stettler, is an animal therapy ranch that helps those with special needs and conditions ranging from PTSD to anxiety. Mark Weber/Stettler Independent
Spirit’s Respite Ranch near Stettler provides support through animal interaction

‘I also come from a family of doers - if something that is needed isn’t there, you just figure it out’

A pedestrian makes their way through the snow in downtown Ottawa on Wednesday, Nov. 25, 2020. THE CANADIAN PRESS/Sean Kilpatrick
Wild winter, drastic swings in store for Canada this year: Weather Network

In British Columbia and the Prairies, forecasters are calling for above-average snowfall levels

NDP Leader John Horgan, left, speaks as local candidate Ravi Kahlon listens during a campaign stop at Kahlon’s home in North Delta, B.C., on April 18, 2017. THE CANADIAN PRESS/Darryl Dyck
A B.C. Ambulance Service paramedic wearing a face mask to curb the spread of COVID-19 moves a stretcher outside an ambulance at Royal Columbia Hospital, in New Westminster, B.C., on Sunday, November 29, 2020. THE CANADIAN PRESS/Darryl Dyck
Top doctor urges Canadians to limit gatherings as ‘deeply concerning’ outbreaks continue

Canada’s active cases currently stand at 63,835, compared to 53,907 a week prior

A Canadian Pacific freight train travels around Morant’s Curve near Lake Louise, Alta., on Monday, Dec. 1, 2014. A study looking at 646 wildlife deaths along the railway tracks in Banff and Yoho national parks in Alberta and British Columbia has found that train speed is one of the biggest factors. THE CANADIAN PRESS/Frank Gunn
Study finds train speed a top factor in wildlife deaths in Banff, Yoho national parks

Research concludes effective mitigation could address train speed and ability of wildlife to see trains

Most Read