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

A ball balances on the rim. New basketball court surfaces and nets will be installed as part of the McBride Street Multi-sport Court Redevelopment project to which Pembina donated $20,000. (Photo: K-J Millar/The Northern View)
Nothing but net for $20,000 Pembina donation

McBride Street multi-sport court redevelopment project in the planning

Ben Spencer has overcome the challenges of having a tenth-grade education and imparts the importance of education by teaching Sm’alygax to students. (Photo: K-J Millar/The Northern View)
Heart of our city: Ben Spencer

Teacher of traditional language and Sm’alygax fluency

FILE – Wet’suwet’en hereditary chiefs have agreed to sign a memorandum on rights and title with B.C. and Ottawa, but elected chiefs are demanding it be called off over lack of consultation. (Thom Barker photo)
Wet’suwet’en hereditary chiefs, Lake Babine Nation get provincial funding for land, title rights

Government says it’s a new, flexible model for future agreements between Canada, B.C. and First Nations.

I want to fly higher. Eva Moore and her brother Leroy Moore are treated to some high pushes from Simon Temple while swinging at Moose Tot Park on April 15. (Photo: K-J Millar/The Northern View)
Photo Gallery: Prince Rupert tots enjoy fun in the sun

Warmer weather is attracting kids of all ages to play outside

The property on which a residential school (pictured) that was torn down years ago in Lower Post is to be the location of a cultural centre. (Indian Residential School History and Dialogue Centre photo)
Lower Post residential school building to be demolished, replaced with cultural centre

Project to be funded by federal and provincial governments, Daylu Dena Council

Vancouver resident Beryl Pye was witness to a “concerning,” spontaneous dance party that spread throughout social groups at Kitsilano Beach on April 16. (Screen grab/Beryl Pye)
VIDEO: Dance party erupts at Vancouver’s Kitsilano Beach to the dismay of onlookers

‘It was a complete disregard for current COVID-19 public health orders,’ says Vancouver resident Beryl Pye

Lord Tweedsmuir’s Tremmel States-Jones jumps a player and the goal line to score a touchdown against the Kelowna Owls in 2019. The face of high school football, along with a majority of other high school sports, could significantly change if a new governance proposal is passed at the B.C. School Sports AGM May 1. (Malin Jordan)
Power struggle: New governance model proposed for B.C. high school sports

Most commissions are against the new model, but B.C. School Sports (BCSS) and its board is in favour

Pall Bearers carrying the coffin of the Duke of Edinburgh, followed by the Prince of Wales, left and Princess Anne, right, into St George’s Chapel for his funeral, at Windsor Castle, in Windsor, England, Saturday April 17, 2021. (Danny Lawson/Pool via AP)
Trudeau announces $200K donation to Duke of Edinburgh award as Prince Philip laid to rest

A tribute to the late prince’s ‘remarkable life and his selfless service,’ the Prime Minister said Saturday

B.C. homeowners are being urged to take steps to prepare for the possibility of a flood by moving equipment and other assets to higher ground. (J.R. Rardon)
‘Entire province faces risk’: B.C. citizens urged to prepare for above-average spring flooding

Larger-than-normal melting snowpack poses a threat to the province as warmer weather touches down

Vancouver-based Doubleview Gold Corp. is developing claims in an area north of Telegraph Creek that occupies an important place in Tahltan oral histories, said Chad Norman Day, president of the Tahltan Central Government. (THE CANADIAN PRESS/HO)
B.C. Indigenous nation opposes mineral exploration in culturally sensitive area

There’s “no way” the Tahltan would ever support a mine there, says Chad Norman Day, president of its central government

Stz’uminus Elder George Harris, Ladysmith Mayor Aaron Stone, and Stz’uminus Chief Roxanne Harris opened the ceremony. (Cole Schisler photo)
Symbolic red dresses rehung along B.C. highway after vandals tore them down

Leaders from Stz’uminus First Nation and the Town of Ladysmith hung new dresses on Sat. April 17

A Western toadlet crosses the centre line of Elk View Road in Chilliwack on Aug. 26, 2010. A tunnel underneath the road has since been installed to help them migrate cross the road. Saturday, April 24 is Save the Frogs Day. (Jenna Hauck/ Progress File)
Unofficial holidays: Here’s what people are celebrating for the week of April 18 to 24

Save the Frogs Day, Love Your Thighs Day and Scream Day are all coming up this week

Local carpenter Tyler Bohn embarked on a quest to create the East Sooke Treehouse, after seeing people build similar structures on a Discovery Channel show. (East Sooke Treehouse Facebook photo)
PHOTOS: B.C. carpenter builds fort inspired by TV’s ‘Treehouse Masters’

The whimsical structure features a wooden walking path, a loft, kitchen – and is now listed on Airbnb

The Attorney General’s Ministry says certain disputes may now be resolved through either a tribunal or the court system, pending its appeal of a B.C. Supreme Court decision that reduced the tribunal’s jurisdiction. (AP Photo/Mark J. Terrill)
Court of Appeal grants partial stay in ruling on B.C. auto injuries

B.C. trial lawyers challenged legislation brought in to cap minor injury awards and move smaller court disputes to the Civil Resolution Tribunal

Most Read