Crown fuel spatial variability and predictability of fire spread

Fire behavior predictions, as well as measures of uncertainty in those predictions, are essential in operational and strategic fire management decisions. While it is becoming common practice to assess uncertainty in fire behavior predictions arising from variability in weather inputs, uncertainty arising from the fire models themselves is difficult to assess. This is the case with fires in crown fuels and the operational fire behavior models used in the United States, where model assumptions, such as fuel homogeneity and steady-state spread, limit the capability of those models to provide reliable results, possibly leading to uncertainties of unknown magnitude. An emerging body of work with dynamic physics-based fire models illustrates the capabilities of those models to address potentially important factors that are not considered by operational models, such as fuel heterogeneity and transitional behaviors.