1,2,3,1,4,5- 1Lusófona University – Porto Campus, Department of Civil Protection, Faculty of Natural Sciences, Engineering and Technologies, Rua Augusto Rosa, 24, 4000-098 Porto, Portugal
- 2Centre for the Research and Technology of Agro-Environmental and Biological Sciences (CITAB), Inov4Agro, University of Trás-os-Montes and Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal
- 3Institute for Nature Conservation and Forests, I.P., Department of Wildfire Management, Rua Dr. Filinto de Morais, N.º128, Ponte de Lima, Portugal
- 4Polytechnic University of Coimbra, RCM2+—Research Center for Management Engineering and Asset Systems Rua da Misericórdia, Lagar dos Cortiços, S. Martinho do Bispo, 3045-093 Coimbra, Portugal
- 5Ci2 –Smart Cities Research Center, Polytechnic University of Tomar, Quinta do Contador | Estrada da Serra, 2300-313, Tomar, Portugal
Wildfires occurring on slopes with canyons represent some of the most challenging and hazardous scenarios for firefighting operations. The interaction between topography, wind and fire dynamics can lead to sudden changes in fire behaviour, including rapid acceleration, increases in fire intensity and eruptive fire behaviour, significantly reducing the time available for operational response and escape.
This study analyses a set of wildfire case studies that occurred in Portugal and the United States, including the Armamar (1985), Yarnell Hill (2013), Caramulo (2013) and Serra da Estrela (2022) wildfires. These events were selected because they exhibited significant fire behaviour changes associated with canyon topography and, in several cases, resulted in firefighter fatalities. The analysis was based on official reports, fire progression records, field observations and photographic evidence, complemented by knowledge gained from experimental studies on fire propagation in slopes with canyons.
The results reveal consistent fire behaviour patterns despite differences in fuel characteristics, meteorological conditions and geographical location. In all cases, the approach of the fire to a canyon was followed by a marked increase in the rate of spread and fire intensity, often accompanied by abrupt changes in propagation direction and eruptive fire behaviour. These transitions contributed to dangerous operational conditions and, in the cases of Armamar, Yarnell Hill and Caramulo, were associated with fatal firefighter entrapments. Observations from the Serra da Estrela wildfire further demonstrate that canyon-induced fire acceleration can occur even without significant changes in weather conditions.
The analysed case studies highlight the critical role of canyon topography in wildfire behaviour and firefighter safety. The findings emphasise the importance of recognising high-risk topographic configurations, improving situational awareness and incorporating fire behaviour knowledge into operational planning and decision-making. These lessons can contribute to safer wildfire suppression strategies in complex terrain.
How to cite: Rodrigues, A., Antunes, F., and Raposo, J.: Fire behaviour and safety challenges in wildfires occurring on slopes with canyons: case studies, 19th Plinius Conference on Mediterranean Risks, Murcia, Spain, 6–9 Oct 2026, Plinius19-107, https://doi.org/10.5194/egusphere-plinius19-107, 2026.
