A chemical Engineering professor at Brigham Young University said the fire behavior model currently being used to predict the spread of wildfires “doesn’t have a lot of physics in it” and “it’s not as good as it could be”. Wildland firefighters have been using the Behave and BehavePlus fire modeling systems for decades.
Using grants from the U.S. Forest Service and the National Science Foundation, Thomas Fletcher expects to add several components to the existing models.
Here are some excerpts from an article on the BYU web site:
Most recently, Fletcher published an article in the International Journal of Wildland Fire detailing how a leaf can burn even with up to 50 percent of its moisture present. This previously unknown fact has serious ramifications for existing models, which often mistakenly factor in the additional time it takes for a leaf’s moisture to evaporate.
“Once a fire gets going, it doesn’t matter if you have wet leaves or bone-dry plants,” Fletcher said. “A big enough fire can ignite the leaves even though there still may be some moisture in the vegetation.”
Over the years, Fletcher and his team have focused on improving three aspects of fire models: the impact of moisture on fires, how wind affects flame and how flame spreads through shrubs.
“The model the fire boss usually runs on his laptop doesn’t have a lot of physics in it,” Fletcher said. “It runs fast and predicts something, but it’s not as good as it can be. We’re trying to improve that model so he can better understand where the fire is, where it’s going, which houses can be saved and where he can safely place firefighters.”
David Weise, supervisory research forester at the USDA Forest Service lab in Riverside, Calif., said Fletcher’s team complements others across the country working to improve the fire models.
“Tom’s fundamental work is providing us with information that can be used in our next generation of models,” Weise said. “The live fuels he’s working on are something we’ve found is important for us to look at, because our current models are dominated by dead fuels.”
Three articles written by Fletcher have been published in the International Journal of Wildland Fire, an official publication of the International Association of Wildland Fire.