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Quantitative assessment method for firefighting danger based on numerical simulation of forest fire spread in canyon
Ao Wang1, Chenghu Wang1,2, Guiyun Gao1,2
1National Institute of Natural Hazards, Ministry of Emergency Management, Beijing, China.
Plos One
|July 24, 2025
Summary
Forest firefighting is complex in mountainous terrain. This study used modeling to assess fire behavior and risk, finding grasslands pose the highest danger.
Area of Science:
- Environmental Science
- Forestry
- Geospatial Analysis
Background:
- Mountainous and canyon regions present complex topography and variable winds, increasing forest fire risks.
- The Muli forest fire (March 28, 2020) highlights the need for advanced risk assessment in such areas.
Purpose of the Study:
- To simulate wind fields and assess forest fire behavior using specialized modeling software.
- To develop and apply a comprehensive forest firefighting risk assessment model.
- To analyze risk variations across different topographical and vegetation types.
Main Methods:
- Utilized WindNinja software for valley wind field simulation.
- Employed FARSITE software to model fire spread rate, fireline intensity, and flame length.
- Developed a risk assessment model incorporating fire behavior, fuel types, topography, and vulnerability indices, using the analytic hierarchy process for index weighting.
Main Results:
- 16% and 54% of the study area showed high and perilous fire spread rates, respectively.
- High and extremely dangerous fireline strengths were found in 5.9% and 0.14% of areas.
- Grasslands exhibited the highest average firefighting danger index (11), followed by deciduous broadleaf (10.3) and evergreen coniferous forests (7.4).
- 16.5% and 21.4% of the area faced high and extremely high firefighting danger levels, respectively.
Conclusions:
- Grasslands represent a critical zone for firefighting prevention and casualty mitigation due to the highest danger index.
- The developed risk assessment model effectively identifies high-risk areas for targeted firefighting strategies.
- Understanding fire behavior and risk variations across diverse terrains and vegetation is crucial for effective forest fire management.
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