Emissions of air pollutants by Canadian wildfires from 2000 to 2004

A wildfire emission model, based on the Canadian Forest Fire Behaviour Prediction System and the Canadian weather forecast Global Environmental Multiscale model, was applied to forest fires that occurred in Canada between 2000 and 2004. Emissions of 21 chemical species and injection heights were calculated hourly for a regular 0.4° grid, with injection heights corresponding to the maximum altitude reached by a convective plume over a fire every hour. Wildfire emissions were compared with anthropogenic fossil fuel combustion sources at provincial, territorial and national levels. The 2002 fire season in central Quebec accounted for ~30, 60 and 80% of the annual primary greenhouse gases, carbon monoxide and black carbon emissions respectively for that province. In 2003, fires represented 60 and 20% of greenhouse gas emissions in Manitoba and British Columbia respectively. During the 2004 fire season in north-western Canada, when area burned was above average, fires were responsible for almost all greenhouse gas emissions occurring in the sparsely populated Yukon Territory and Northwest Territories. On average, between 2000 and 2004, fires contributed 10, 30 and 40% of Canadian annual greenhouse gases, CO and black carbon emissions respectively. This methodology for calculating wildland fire emissions is also applicable to other regions of the world.