Description

Forest fuel loads are unnaturally high in the Sierra Nevada. The US Forest Service is currently preparing a prescribed fire program to reduce fuels in the region. Modeling, both short-term and long-term, direct and cumulative impacts to rural communities meets Federal mandates for analyses of social impacts and environmental justice. For assessing social factors, we have first used meteorological and terrain data. Collected or interpolated data reflects the probability distribution of smoke accumulation in a landscape polygon from fires at various distances and with differing intensities. Collapsing the smoke probability distribution maps together for each season provides a mapping layer with ordinal data to assess the cumulative likelihood of losses to air quality and visual quality from smoke across the Sierra Nevada region. Our social impacts analysis has concentrated on three target populations: (1) fire fighting crews; (2) children less than 10 years of age; and (3) adults 60 years or older. We cannot easily characterize the impacts to crews because they are mobile populations; the last two groups are local and place-based. Census data reveal the most susceptible populations based on places with high proportions of sensitive age cohorts. The intersection of both relative risk of smoke accumulation and the location of at-risk populations predicts for the US Forest Service areas of community sensitivity. Another key factor has been cultural differences across the Sierra Nevada region. An analysis of subregion differences shows cultural differences and attitudes toward smoke from forest burning. In the Modoc Plateau and Sierra / Cascade axis, mostly rural residents rarely file complaints about smoke; on the contrary, tolerance for smoke is lower among all age groups on both sides of the southern Sierra Nevada. Environmental justice analysis investigates whether the effects of smoke on loss of air quality and visual quality fall disproportionately on poor people or on people from minority ethnic and cultural backgrounds. Highest rates of poverty in the Sierra Nevada region are concentrated in Modoc and Lassen counties in the north and in rural foothill Tulare County. These areas also coincide with high populations. Scheduling prescribed fires will affect residents in the Sierra Nevada differently, and attention to effects on sensitive and minority human populations will make prescribing fire more acceptable to rural communities.