PARENT SESSION
Oral Session #54: Fire Ecology -- Trees, forests, woodlands.
Presiding: E. Menges
Wednesday, August 7. 8:00 AM to 11:30 AM. Apache Meeting Room, TCC.

Modeling the effects of fire hazard reduction activities on wildfire behavior.

BALICE, RANDY^*,1, KOCH, STEVEN¹, ¹ Los Alamos National Laboratory, Los Alamos, NM

ABSTRACT- To better understand wildfire hazards in the Los Alamos region, we developed a wildfire behavior and soil erosion modeling system for use in research and management activities. This system is based on Farsite and the Universal Soil Loss Equation, but is parameterized with local data and has undergone sensitivity and validation analyses. We used the wildfire behavior components, in a Monte Carlo setting, to evaluate the effects of forest thinning on 1) the average number of acres burned per wildfire and 2) the average economic loss to Los Alamos National Laboratory (LANL) per wildfire. Lightning strikes were used to initialize simulations of 47 wildfires. First, these fires were simulated under pre-thinning conditions. Then, the input data layers were modified to reflect thinning to fuelbreak specifications in 800 acres of ponderosa pine forests. Next, the 47 wildfires were simulated again under identical conditions except for the changes imposed by the thinning operations. The average area burned per fire was 645 hectares (1594 acres) before thinning and 370 hectares (914 acres) after thinning, a 43 percent reduction. When comparing the costs of 1) thinning, 2) fire suppression, 3) burned buildings, and 4) lost income before thinning and after thinning, thinning reduced the per-wildfire expected loss to LANL by $44M, or 56 percent.

KEY WORDS: fire hazard reduction, wildfire behavior, Monte Carlo simulations