The Arctic is undergoing a rapid thaw as rising temperatures bring permafrost to an end, and a groundbreaking new study unveils how the region is on the brink of some serious fires – with global implications for us all.
Raging Fires in an Arctic that is Thawing Permafrost
The thawing of permafrost in the Subarctic and Arctic regions of northern Canada and Siberia will drive an unfreezing that will bring a dramatic increase in wildfires, as predicted by climate models; the study is published this week in Nature Communications.
Global temperature rise is projected to thaw the previously frozen soil in these high-latitude regions quickly, therefore causing abrupt decrease of soil moisture. That will bring us the conditions that are ideal for larger, more frequent wildfires.
To help tease out the impacts of human-caused climate change versus natural variability, the researchers harnessed an ensemble of 50 different climate simulations. The researchers found that by the mid-to-late 21st century, the anthropogenic impact on permafrost thaw will become dominant, paving the way for a deep burning of the northern tundra.
A Self-Destructive Feedback Loop
The research also underscores a pernicious positive feedback cycle that could arise between wildfires and permafrost thaw in the Arctic.
The emissions of carbon dioxide and black carbon and organic carbon into the atmosphere, when released into the environment as a result of wildfires, can exacerbate global concerns such as climate change and further thaw permafrost. This will, in return, give more to burn for the following fires and so on, thus continuing the cycle.
In addition, the scientists say the warming atmosphere will also “increase vegetation growth in northern high latitudes (in a feedback known as ‘CO2 fertilisation’) and thus provide more fuel for these awakening fires”.
The scientists suggest that to better understand these complex interactions among permafrost, soil moisture and subsequent fire dynamics, Earth system models should be developed with higher resolution representation of small-scale hydrological processes in the permafrost landscape.
Conclusion
The results were “a very worrying outlook for the future of a flammable Arctic,” where a permafrost thaw that releases even just oubreaks could lead to large fires with profound impacts on The Arctic ecosystem, as well as climate change throughout the world. Improved descriptions of these processes are critical for developing more realistic models to support policy and management decisions aimed at conserving this unique resource.
