Investigation of the decline in reported smoking-caused wildfires in the USA from 2000 to 2011

The number of smoking-caused wildfires has been falling nationwide. In national forests in 2011, smoking-caused wildfires represented only 10% of their 1980 level. No other cause of wildfire has experienced this level of decline. For 12 states, we evaluate the rate of smoking-caused wildfires and find it is a function of weather, other ignitions, the number of adult smokers, the presence of improved wildfire cause-determination methods, and whether a state required the sale of less fire-prone cigarettes. We find the decline in adult smoking rates has led to a reduction of smoking-caused fires by 9%. The finding that less fire-prone cigarettes appear successful at limiting wildfire starts – by 23% – is a likely unintended benefit of a technology aimed at reducing fire fatalities in residences. We also find that the improvements in wildfire cause determination have resulted in a reduction in smoking-classified fires by 48%. Although improved wildfire cause-determination methods do not necessarily reduce the number of wildfires, they ensure that the causes of wildfire are accurately tracked. Accurate wildfire cause determination can, however, result in targeting wildfire-prevention programs to specific fire-cause categories, which can lead to a reduction in the overall number of wildfires.