Tuesday, 13 November 2001: 10:50 AM
Quantile characteristics of forest fires in Saskatchewan
The fire weather and fire behavior characteristics of 8296 forest fires in Saskatchewan were studied to assess the significance of various fields at determining fire detection. The median fire (the fiftieth percentile) detected within the primary zone is discovered around 3:15 PM at approximately 0.1 hectares in size. Assuming the fire has reached equilibrium, the rate of spread is typically 2 m/min and has a head fire intensity of 1500 kW/m. Trees within the fire will likely be candling but not yet developing into a solid crown flame front. Mean values for fires detected within the secondary zone are larger that those in the primary zone indicating that fires are generally detected at more advanced stages of growth - likely a result of less intensive detection efforts. A comparison of the probability of sustained ignition within dry lodgepole pine with the observed quantile distribution of ISI at time of ignition within C3 fuels suggests that the distribution is an appropriate representation of the product of the probabilities of arrival and of detection. This can be extended to using ROS and HFI , thus extending the probability calculations to all fuel types.