Rising temperatures have caused smoldering “zombie fires” that threaten Arctic ecosystems and could release vast amounts of greenhouse gases
A startling new discovery has been made about the ongoing wildfires in the Arctic: zombie fires, also known as holdover fires, which occur when previous seasons’ fires do not completely die, but smolder in the carbon-rich peat underground over the winter — often reigniting as wildfires when spring arrives.
“We know little about the consequences of holdover fires in the Arctic, except that they represent momentum in the climate system and can mean that severe fires in one year set the stage for more burning the next summer,” wrote Dr. Meritt Turetsky, coauthor of the study published in Nature Geoscience.
Another startling discovery is the burning of fire in regions which were earlier believed to be fire-resistant. In the northern regions of the tundra, fire-resistant vegetation like dwarf shrubs, sedges, grass, moss, and even surface peats are starting to burn. Wet landscapes like bogs, fens, and marshes are also vulnerable.
One possible effect of this phenomenon is increased levels of greenhouse gases rising from the soil into the atmosphere. The fires also pose a risk to human life. Beyond the danger to houses and farms, the abrupt thawing of frozen tundra due to wildfires can cause flooding as well as new pits and craters, the study warned.
“We need global cooperation, investment, and action in monitoring fires, including learning from Indigenous and local communities how fire is traditionally used,” wrote the study’s lead author Dr. Jessica McCarty, geographer at Miami University. “We need new permafrost- and peat-sensitive approaches to wildland fire fighting to save the Arctic — there’s no time to lose.”