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

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

The mandate is in keeping with recommendations made by Dr. Bonnie Henry. (CSRD photo)
Mask use now required at CSRD office, public facilities

The mandate comes after Dr. Bonnie Henry strongly recommended their use

Mara Lake is one of the significant water resources across the Okanagan-Shuswap region that will fall under increasing sustainability pressure as the anticipated population growth for the region continues in this century. (File photo)
Okanagan Valley water supply sustainability reaching a critical point: Global expert

Global expert says Okanagan Basin Water Board offers sustainable path forward

Black Press file photo
Golden/Field crime rate drops for fourth straight year

The decrease was reported by Stats Canada, who recently released their yearly crime stats for B.C.

Dr. Trina Larsen Soles recommends cotton face coverings, as they are the most effective. (Claire Palmer photo)
Golden’s physicians warn of second wave

It is now expected that everyone wear a mask while indoors in public places

Morgues.
Morning Start: Cruise ships have their own morgues

Your morning start for Friday, Oct. 30, 2020

Physical distancing signs are a common sight in B.C. stores and businesses. THE CANADIAN PRESS
272 more COVID-19 cases for B.C., outbreak at oil sands project

Three new health care outbreaks, three declared over

Vernon Council voted in favour of implementing a 500-metre buffer between all new cannabis stores in the city at its meeting Monday, Oct. 26, 2020. (Black Press files)
New cannabis shops in Vernon will need to stay 500m apart

The distancing rule won’t apply to existing stores, including the six currently in downtown core

A fundraising initiative has been set up to help Mirjana Komljenovic, who has been diagnosed with Hermansky Pudlak Syndome and requires $2,000 a month to cover the costs of her medication. (gofundme.com)
Fundraiser created to help Summerland woman with rare condition

Mirjana Komljenovic requires costly medication to treat Hermansky Pudlak Syndome

Heather Pescada is Ms. Halloween and when COVID threatened to ruin her haunted fun, she got creative, inventing a six foot candy chute at her Summerland, Trout Creek home.
(Peskelly Family Facebook page)
Okanagan Halloween house invents huge candy chute

The six foot chute looks like the snake from Nightmare Before Christmas

This house at 414 Royal Ave. became notorious for its residents’ and visitors’ penchant for attracting police. It was also the site of a gruesome torture in August 2018. It was demolished in 2019. KTW
6-year sentence for Kamloops man who helped carve ‘rat’ into flesh of fellow gang member

Ricky Dennis was one of three men involved in the August 2018 attack

Join Black Press Media and Do Some Good

Pay it Forward program supports local businesses in their community giving

Cpl. Nathan Berze, media officer for the Mission RCMP, giving an update on the investigation at 11:30 a.m., Oct. 30. Patrick Penner photo.
VIDEO: Prisoner convicted of first-degree murder still at large from Mission Institution

When 10 p.m. count was conducted, staff discovered Roderick Muchikekwanape had disappeared

Among the pumpkin carvings created this year by Rick Chong of Abbotsford is this tribute to fallen officer Cont. Allan Young.
Abbotsford pumpkin carver’s creations include fallen police officer

Rick Chong carves and displays 30 pumpkins every year

Most Read