Zombie fires

This past weekend saw our first of what will likely be many air quality alerts due to wildfire smoke this year. Several years of drought, including a very low snowfall this past winter are making for very dry conditions. But another factor is also creating increased risk: zombie fires.

Zombie fires and those that go underground for the winter, literally. With hot summers and dry conditions, both becoming more frequent with climate change, fires are burning deeper into organic soils. These soils, found in places like the boreal forest, can harbour the fire through the winter. In the spring, these fires can come back to the surface and expand.

This is the first year that I remember hearing about zombie fires. And while they aren’t a new phenomenon, they are expected to have bigger impacts in the future compared to the past.

Scholten and colleagues (2021) studied these overwintering fires in the boreal forest in northern US (Alaska) and Canada (Northwest Territories). Between 2002 and 2018 these fires accounted for 0.8 percent of the total burned area; but that stat doesn’t tell us everything. In one year, zombie fires accounted for 38 percent of the total burned area.

In looking up information for this blog, I came across an article in a magazine for insurance companies. The article is discussing the current fire near Fort Nelson, BC. In it, Gambrill discusses how zombie fires have the potential to make this fire season worse. Which, of course, has implications for insurance.

Detection might be key for this. Scholten and colleagues provide some tools for identifying the zombie fires and potentially looking at pre-emptive or at least early responses. The question is whether any government or agency will both have access to and dedicate the funds to respond.