The underground flames that refuse to die even in winter
In short: Forest fires often appear extinguished when the seasons change, but a phenomenon known as 'zombie fires' tells a different story. These stealthy blazes smolder beneath the surface all winter long, waiting for the spring thaw to reemerge and reignite the landscape.
For years, the scientific consensus suggested that 'overwinter' fires survived by consuming carbon-rich organic matter, specifically thick layers of peat. However, new field research led by biologist Jennifer Baltzer of Canada's Wilfrid Laurier University has overturned this assumption. By examining nine specific overwinter sites, the team discovered that these fires were not primarily fueled by peat. The researchers utilized data from previous satellite observations to select their study locations. This allowed them to focus on specific areas where the phenomenon was most evident.
Instead, the study found that these fires often occur in drier, upland areas characterized by dense tree populations. The researchers discovered that the flames were actually smoldering underground within woody tree roots. This unexpected mechanism allows the fire to remain active even as shortening days and dropping temperatures limit surface wildfire activity in the Northern Hemisphere. The discovery of this root-based fuel source was a significant surprise to the scientific team. It contradicts the previous hypothesis regarding how these flames sustain their heat.
The prevalence of these fires is increasing in Arctic forests, a trend linked to the broader impacts of climate change. This phenomenon was first highlighted by a 2021 satellite-based study, which showed that these underground embers could be identified through visual cues in space. Shared during April's European Geosciences Union General Assembly, this evidence indicates that wildfire forecasting and observation techniques need updating to address such underground risks. While satellites can detect these sites, ground-level verification by firefighters has since confirmed the findings. This dual-layer approach provides a more complete picture of the ecological impact.
Opens the Intellect+ feed with this card first. Swipe up for the next one.
Sources
- Summary by Intellect · source: Zombie Fires Are on the Rise
- Also: How
To cite this card, link to https://intellectplus.co.uk/app/science-zombie-fires-are-on-the-rise.
How we source, check and correct cards: Editorial standards.
General information, not professional advice. Spotted an error? Flag the card or see corrections and complaints.
Intellect Plus is a visual educational discovery platform for exploring fascinating facts and ideas. Brain Food, Not Brain Rot. What is Intellect Plus?
Related
More in Science · Latest · A–Z · All topics
