Description

We characterized the historical, current, and future wildland fire smoke emissions on National Forests and Grasslands of the western United States. This information provided a basis for summary interpretations included in the U.S. Forest Service report "Protecting People and Sustaining Resources in Fire-Adapted Ecosystems, A Cohesive Strategy” (Laverty et al. 2000). The report was developed to respond to the Congressional U.S. General Accounting Office (GAO) report, Western National Forests: A Cohesive Strategy is Needed to Address Catastrophic Wildfire threats” (GAO/RCED-99-65). The key information used to develop the strategic plan for restoration of forests and rangelands in the Lower 48 states was the historical and current fire regime condition class composition from Hardy et al. (2000) and the smoke emissions stratification of Ottmar et al. (2000). The fire regime condition classes are based on ecosystem vegetation and disturbance regime departure from historical regimes. Using this data we assessed the historical levels of wildland fire smoke production from "natural” fires, compared these to amounts for different periods from 1860 to 2000, and developed projections into the future. The future projections were for two strategies of National Forest and Grassland management: 1) continuation of current management; and 2) implementation of the cohesive strategy. We conclude that total smoke emissions from recent historic wildfire, wildland fire use (prescribed natural fire), and prescribed fire are substantially less than the historical amounts of "natural” fires, but that smoke emissions from wildfires have steadily increasing from the 1980s to the current period. Future projections indicate that continuation of current management will result in continued increase of smoke emissions from wildfires that approach historical levels. In contrast, implementation of the cohesive strategy is projected to reduce wildfire smoke emissions by a substantial percentage in about 15 years. Even though this is associated with some increase in smoke emissions from wildland fire use and prescribed fire, the total smoke emissions for the cohesive strategy are predicted to be substantially less than for continuation of current management, because of the reduction in wildfire smoke emissions.