How Canadian Wildfires Are Thawing Permafrost and Accelerating Climate Change
Imagine a sleeping giant buried beneath the frozen soils of Canada's northern wilderness—a giant made of ancient carbon, preserved in ice for thousands of years. Now, imagine that giant is waking up, not to the sound of an alarm, but to the crackle of advancing flames. In Canada's boreal and Arctic regions, a dangerous feedback loop is unfolding: climate change is fueling increasingly severe wildfires, which in turn are thawing permafrost at an alarming rate, releasing even more carbon into the atmosphere and further accelerating climate change 1 2 .
hectares burned in the 2025 wildfire season, the second worst in Canadian history 5
the amount of carbon stored in permafrost compared to the entire atmosphere 1
Beyond the immediate destruction lies a deeper, more insidious threat—the potential for these fires to permanently alter the very foundation of northern ecosystems and push our climate system past a point of no return.
Permafrost is ground that remains completely frozen for at least two consecutive years. It underlies vast stretches of the Northern Hemisphere, storing enormous amounts of dead plant material that accumulated over millennia without fully decomposing due to the cold, wet conditions. This makes permafrost one of the Earth's largest natural reservoirs of carbon, holding nearly twice as much carbon as currently exists in the entire atmosphere 1 .
In its natural state, permafrost is protected by a complex natural insulation system. The organic layer on top—comprising mosses, lichens, and decaying plant matter—acts as a protective blanket, shielding the frozen ground below from summer heat 2 . Above this, the boreal forest canopy provides shade and helps regulate ground temperatures. This delicate system maintained equilibrium for thousands of years, but now it's being disrupted.
Visualization of permafrost layers and the impact of fire on insulation
When wildfires sweep across these northern landscapes, they don't just burn trees—they consume the protective organic layer that insulates the permafrost 2 . With this natural blanket gone, the dark, exposed soil absorbs more solar radiation. The result is a cascade of changes: soil temperatures rise, the active layer (the seasonally thawed surface soil) thickens, and the permafrost beneath begins to thaw, sometimes irreversibly 2 .
The link between climate change and worsening wildfire seasons is now unmistakable. Rapid warming in northern latitudes is extending the fire weather season, increasing lightning ignitions (a primary cause of remote fires), and creating heat-stressed vegetation that acts as ready fuel for larger, more intense fires 1 8 .
| Indicator | Change Observed | Significance |
|---|---|---|
| Near-surface permafrost | 7% loss in last 30 years (1.6 million km²) 3 | Irreversible degradation of foundational landscape element |
| Wildfire emissions from Alaska and Canada | 106% increase over past 20 years 3 | Dramatic intensification of fire activity and carbon release |
| Arctic land monitoring | 80% not represented by year-round CO₂ and CH₄ monitoring 3 | Critical data gaps limiting our understanding |
The situation has become so severe that smoke from Canadian wildfires now regularly chokes cities across North America and even reaches as far as Europe, making what happens in these remote northern landscapes a global concern 1 8 .
Increased fire weather creates conditions where wildfires can start more easily and spread more rapidly.
Until recently, the complex relationship between permafrost thaw and wildfires remained poorly understood. Then, in 2024, a landmark study published in Nature Communications provided startling evidence of impending regime shifts in these systems 6 .
Researchers used the Community Earth System Model version 2 (CESM2) to run 50 different simulations of future climate under the SSP3-7.0 scenario (a moderate-to-high greenhouse gas emission pathway) 6 .
This "large ensemble" approach was crucial—by running the model multiple times with slight variations in initial conditions, scientists could distinguish between natural climate variability and the forced response to human-caused climate change. The model specifically captured the coupling between permafrost, hydrology, and atmosphere—a level of integration that most previous Earth system models lacked 6 .
The findings revealed a nonlinear, threshold response that surprised even the researchers. Rather than a gradual thaw, the model projected rapid, catastrophic permafrost collapse in several critical regions between 2040-2060 6 .
| Parameter | 2040 Value | 2060 Value | Change |
|---|---|---|---|
| Active Layer Thickness | 0.93 m | 4.09 m | +340% |
| Soil Ice Content | 668 kg/m² | 149 kg/m² | -78% |
| Upper Soil Moisture | 71.1 ± 2.9 kg/m² | 51.4 ± 3.5 kg/m² | -28% |
| Risk Factor | Change After Permafrost Thaw | Effect on Wildfires |
|---|---|---|
| Soil Moisture | 28% decrease in upper layers | Increases fuel availability and flammability |
| Surface Temperature | Significant warming | Dries vegetation faster |
| Relative Humidity | Notable reduction | Creates drier microclimate |
| Lightning Ignitions | Projected increase with warming | More ignition sources for fires |
Projected timeline of permafrost thaw and associated wildfire risk increase
Understanding these complex interactions requires sophisticated tools spanning field observations, remote sensing, and computational modeling.
These installations measure the exchange of greenhouse gases (CO₂ and CH₄) between the ground and atmosphere. The Arctic Boreal Carbon (ABC) Flux Network is strategically expanding these towers across remote areas where monitoring is currently limited 3 .
This remote sensing technology can detect ground surface deformation with centimeter-scale precision, allowing researchers to track permafrost thaw and ground subsidence across vast, remote areas over time .
These specialized sensors distinguish between thawed and frozen ground regardless of temperature, sending alerts when excessive thawing occurs. Used by both industry and researchers, they require no complex scientific interpretation and can be installed with hand tools in minutes 7 .
Advanced computational models like those being developed by Woodwell Climate and University of Alaska Fairbanks combine field observations with satellite data to create high-resolution (1km) simulations of permafrost emissions—a vast improvement over current global models (100km resolution) 3 .
This research method evaluates temporal changes by measuring permafrost conditions across multiple sites representing different stages of degradation and recovery. It helps scientists understand both immediate and long-term impacts of wildfires 2 .
Collaborative research that incorporates traditional ecological knowledge provides valuable insights into long-term environmental changes and effective land management practices that have sustained northern ecosystems for generations 4 .
"There's too much fire now" - Gwich'in Athabascan community member, Fort Yukon, Alaska 4
For northern Indigenous communities, these changes are not theoretical—they're transforming daily life and threatening cultural survival. In Fort Yukon, Alaska, Gwich'in Athabascan people report that "there's too much fire now" 4 . The increasing smoke exposure threatens the health of community members, particularly elders, and makes the subsistence lifestyle harder and more dangerous 4 .
Edward Alexander, Senior Arctic Lead at Woodwell Climate, coined the term "wildland cultural interface" to capture the reality that fire-prone landscapes, culture, and community are intertwined in tangible and emotional ways for Indigenous peoples 4 . Their knowledge and cultural burning practices reflect millennia of experience with fire on the landscape, offering valuable insights for modern fire management 1 4 .
Increased smoke exposure affects respiratory health, particularly for elders and children with pre-existing conditions.
Subsistence hunting and gathering become more difficult as fire alters animal habitats and traditional harvesting areas.
Thawing permafrost damages buildings, roads, and other critical infrastructure in northern communities.
Traditional knowledge systems and cultural practices are threatened by rapidly changing environmental conditions.
Despite the dire outlook, researchers and communities are developing innovative responses. Targeted fire suppression in areas with carbon-rich "yedoma" permafrost (high in ice and carbon content) is emerging as a cost-effective climate solution 1 4 .
per ton of carbon emissions prevented through targeted suppression 1
acres of yedoma land protected under 2023 Yukon Flats pilot project 4
of Arctic land not monitored year-round for CO₂ and CH₄ emissions 3
"The goal is not to eliminate fire but to bring fires back to historical or pre-climate change levels" - Dr. Kayla Mathes of Woodwell Climate 4
In 2023, a pilot project in Yukon Flats, Alaska, became the first fire management policy to explicitly enhance suppression to protect carbon and climate, covering 1.6 million acres of yedoma land 4 . This approach differs fundamentally from fire suppression in lower latitudes, where it has led to fuel buildup. Northern boreal forests don't share this history, and climate change—not suppression—is the overwhelming driver of increased fire activity 4 .
The ultimate vision integrates multiple strategies: scientific fire suppression, the revitalization of Indigenous fire stewardship, and cultural burning practices that cultivate a healthier relationship between fire and the landscape 1 4 .
The interplay between wildfires and permafrost represents one of climate change's most dangerous feedback loops—but it's not yet a lost cause.
While the CESM2 model projections suggest abrupt changes could begin in the mid-century, the timeline isn't fixed 6 .
The combination of advanced monitoring, targeted suppression, and Indigenous knowledge offers a comprehensive strategy 3 4 .
Reducing fossil fuel emissions remains the single most important step to limit long-term risk 1 .
As one community member from Fort Yukon reminded scientists, their knowledge of changing wildfire patterns long preceded Western data reaching their village 4 . This underscores a crucial truth: addressing the twin crises of wildfires and permafrost thaw will require all forms of knowledge—scientific and Indigenous, global and local—working together to protect the frozen giant sleeping beneath the northern forests before it awakens completely.