A destructive cycle is worsening throughout the world’s arctic regions.
Numerous areas throughout Earth have “permafrost,” or layers of soil and sediment beneath the surface that remain frozen no matter the season. Humans, in their hubris, believed the frost to be “permanent,” but human-driven climate change, through the burning of fossil fuels like coal, oil, and gas, is shaking that stability.
Wildfires have recently burned more and more acres throughout the world’s arctic regions, causing unprecedented permafrost thawing and soil drying, according to a recent study published in Nature Communications. The abrupt drying is causing a subsequent abrupt increase in wildfires, continuing the vicious cycle.
“The abrupt soil drying and intensified atmospheric aridity can facilitate an abrupt increase in fires, related to biomass and peat burning over the permafrost regions,” the researchers said. “The abrupt increase in sensible heat fluxes can intensify the warming of near-surface air temperature and enhance atmospheric aridity, further promoting wildfire intensity.”
Researchers estimate burned acreage throughout arctic areas will more than double after permafrost thaw, while historically fire-prone areas do not see changes. Additionally, once soil moisture is lost, it isn’t regained until after a long recovery period which researchers estimate to be over two years, further prolonging wildfire activity.
The researchers said their hypothesis was confirmed in the study: Soil moisture loss triggers a cascading effect in arctic areas, leading to rapid biomass burning, atmospheric drying, and an abrupt increase in wildfires and emissions.
“The abrupt increase in wildfires over the historical permafrost regions can contribute to changes in net terrestrial carbon uptake,” the researchers said. “Furthermore, the contribution of carbon release from wildfires to the net terrestrial carbon balance in these regions accelerates after the mid-21st century.”
It’s not the first study to link permafrost burning to increased emissions. A NASA study last year looked specifically at how wildfires throughout Alaska’s largest river delta were affecting that area’s permafrost and found clusters of methane “hot spots” where wildfires burned into tundra.
“We find that [methane] hotspots are roughly 29 percent more likely on average in tundra that burned within the last 50 years compared with unburned areas, and that this effect is nearly tripled along burn scar perimeters that are delineated by surface water features,” the researchers said. “Our results indicate that the changes following tundra fire favor the complex environmental conditions needed to generate emission hotspots.”
READ MORE: Burning Alaskan permafrost increasing methane emissions
