Peatlands are a massive carbon sink, but they are burning more often due to climate change

In recent years, Sam Hunter has noticed a difference in the peatland surrounding his community in northern Ontario.

"I remember two years ago we built a fire while we were fishing on top of the snow, and then I noticed that we had to pour water on that fire," he said.

"Even though it was winter, there was a lot of snow and it was still burning two days later."

Hunter is from the Cree community of Peawanuck, nestled along the Winisk River south of Hudson Bay. He's the natural resource monitor in the community, which sits so far north it is surrounded by peatlands — a type of wetland where waterlogged conditions prevent plants from fully decomposing.

By definition, peatlands are wet environments, but a warming climate has meant they sometimes get dry enough for fires to take hold.

"When it burns in the summer, it just burns right down until there's nothing left. It will just keep on burning," Hunter said.

Because peatlands contain so much plant material, they are massive carbon sinks — natural or artificial sources that absorb more carbon from the atmosphere than they release.

Carbon sinks can also include forests, the ocean and soil; they differ from carbon sources, such as the burning of fossil fuels that release carbon dioxide (which can warm the planet, contributing to climate change) into the atmosphere. 

The International Union for Conservation of Nature says peatlands make up the world's largest natural terrestrial carbon store.

Sarah Finkelstein is a professor with the University of Toronto's department of earth sciences and works closely with Indigenous communities in Ontario's far north to better understand peatlands.

Finkelstein calls Canada a "peatland superpower" because the unique wetlands cover over 1 million square kilometres of the country's landmass.

"They're a very important part of our landscape and the history of our landscape," she said.

Part of Finkelstein's research is looking back more than 10,000 years ago, when the last ice age ended in what is now Canada, and how peatlands have changed.

"We can collect core samples of that mud and actually understand something about the history of those environments, like climate history, vegetation change, the impacts of disturbance," she said.