The Grass Fires on Slopes Experiment

Fire-atmosphere interactions and their role on fire behavior in complex terrain are not well understood. While there have been many accounts of fire behavior in mountainous areas, there exists few, if any, studies that have focused on obtaining in situ meteorological and fire behavior data in complex terrain. The Grass Fires on Slopes Experiment aims to measure fire-atmosphere interactions during experimental head fires on sloped terrain. The first pilot experiment was conducted on 24 June 2010 and was associated with strong (8 m/s) cross-slope winds. Preliminary results show that even under strong cross winds, the sensible heat flux from the fire front of 100 kW m-2 was strong enough to generate updrafts of 7 m/s. Fire-induced winds were also observed as the fire front crossed the slope. A pressure drop of 0.5 mb was observed just before the fire front passage. Additionally, warm air advection was observed to occur within the lowest few meters above the surface ahead of the fire front.