How far can wildfire spread in a single day?

Research SummaryHow far can wildfire spread in a single day?

Understanding where wildfires start and how they spread from natural areas to communities is vital for creating effective plans to reduce risks and protect people.

Aerial photo of wildfire spreading from across a lake

In “Mapping the Distance Between Fire Hazard and Disaster for Communities in Canadian Forests,” Dr. Mike Flannigan and co-researchers used a fire simulation model to chart fire movement and speed for nearly 2,000 Canadian communities in forested areas.

They figured out how much fires spread each day on average by looking at different places and other factors.


Key terms

  • Fireshed: Source area or the fire ignition location
  • Fire pathway: Fastest route measured in minutes by which a fire may spread from fireshed to community
  • Fire corridor: A common channel shared by fire pathways that converge towards the same community

Key findings

Here is a snapshot of their findings:

  • Fireshed sizes are larger in the north
  • Many communities have significant directional trends in fires
  • Directional trends are stronger in the Boreal Plains and Shields than the Rocky Mountain area

Importantly, the researchers determined how far fires generally are from communities. At the fastest simulated spread rate, a fire could hit a community from about five, 12, and 18 km away in roughly one, two, and three days, respectively.

They also found average daily spread distances increased from south to north. For example, spread distances were shortest in the Pacific Maritime, Atlantic Maritime and Boreal Plain Ecozones.

This research reveals that factors beyond fuel, like weather conditions and where a fire starts, are key in shaping which way wildfires spread.


Authors

Xianli Wang, Tom Swystun, Colin B. McFayden, Sandy Erni, Jacqueline Oliver, Stephen W. Taylor, Mike Flannigan


MLA Citation

Wang, Xianli, et al. “Mapping the Distance Between Fire Hazard and Disaster for Communities in Canadian Forests.” Global Change Biology, vol. 30, no. 3, March 2024. https://doi.org/10.1111/gcb.17221