Fuel layer specific pollutant emission factors for fire prone forest ecosystems of the western U.S. and Canada
Urbanski, S., R. Long, H. Halliday, A. Habel, E. Lincoln, AND M. Landis. Fuel layer specific pollutant emission factors for fire prone forest ecosystems of the western U.S. and Canada. Atmospheric Environment: X. Elsevier B.V., Amsterdam, Netherlands, , 0000, (2022). https://doi.org/10.1016/j.aeaoa.2022.100188
This study has addressed two important gaps in the biomass burning EF literature – Douglas fir canopy fuels and black spruce / jack pine surface fuels. These forest types are a significant portion of forests consumed by wildfires in western Unites States and Canada, a region experiencing significant increases in burned area and pollutant emissions. This study also examines the variability of pollutant emissions across components of ponderosa pine forest surface fuel beds: needles, fine woody debris, and cones. While emissions from ponderosa pine surface fuels have been studied previously, our study is the first to quantify EFs for cones, an important component of the litter layer. We also found that EFTRS was correlated with MCE, EFSO2 was not correlated with MCE, and that a factor of 2 difference in fuel S content did not have a discernible effect on emission of either TRS or SO2 emissions.
Wildland fires are a major source of gases and aerosols, and the production, dispersion, and transformation of fire emissions have significant ambient air quality impacts and climate interactions. The increase in the wildfire area burned and severity across the US and Canada in recent decades has led to increased interest in expanding the use of prescribed fires as a forest management tool. While the primary goal of prescribed fire use is to limit the loss of life and property and ecosystem damage by constraining the growth and severity of future wildfires, a potential additional benefit of prescribed fire - reduction in the adverse impacts of smoke production and greenhouse gas emissions - has recently gained the interest of land management agencies and policy makers in the United States and other nations. The evaluation of prescribed fire/wildfire scenarios and the potential mitigation of adverse impacts on air quality and GHGs requires fuel layer specific pollutant emission factors (EF) for fire prone forest ecosystems. Our study addresses this need by with laboratory experiments measuring EFs for CO2, CO, CH4, C2H2, H2CO, CH2O2, HCN, NO, NO2, SO2, and total reduced sulfur (TRS) for the burning of individual fuel components from three forest ecosystems which account for a large share of wildfire burned area and emissions in the western US and Canada - Douglas fir, ponderosa pine, and black spruce/jack pine.