Many studies have shown that the huge permafrost layers under the Arctic are melting.
A newly published study shows that the permafrost in northern regions in the boreal forest may be melting much faster than previously thought, up to 25 per cent faster, due to wildfires. This means current models of permafrost thawing and CO2 release are underestimating the situation.
Carolyn Gibson is lead author of the research. She is a PhD student at the University of Guelph, Ontario, but completed the research as a Master’s student at the University of Alberta.Listen
The finding of the research were published in the August 2, 2018 edition of Nature Communications under the title, Wildfire as a major driver of recent permafrost thaw in boreal peatlands” ( open access HERE)
Across the northern reaches of the boreal forest vast patches of permafrost several metres thick, lies under a relatively thin layer of soil. That soil supports bushes, grasses, lichens, and small trees.
What the study found was that when a wildfire races through and burns that off, the blackened ground is exposed and absorbs much more heat from the sun.
That heat is absorbed downward, melting the supporting permafrost.
In addition to making the ground soft and soggy creating travelling problems for large animals and people, and damage to infrastructure such as roads in those regions, permafrost contains vast resources of trapped CO2 which is then released into the atmosphere.
Gibson says because plant growth in slow in northern regions, the effects of a wildfire can last decades.
In addition, studies have shown that wildfires are becoming larger and more common, further exacerbating the situation.
Gibson says the research is significant as previous studies and predictions of permafrost melt have not taken into account the significant effects of wildfires on the thawing of permafrost.