Wildfire impacts on Spanish municipal population.

This paper analyzes the impact that different kinds of wildfires exert on population size of Spanish municipalities covering the 1986-2015 period, using recent developments in difference-in-differences estimation methods. The goal of the methodology is dealing with different wildfire events on several municipalities by considering as the initial time the first wildfire for all of them. Qualitative and quantitative effects are analyzed. Severity is measured as qualitative indicator by two ways. First, as major agricultural areas affected by dividing the sample in four quartiles according to the extension of the burned agricultural area. Second, as the highest proportion of total burned areas over total municipal area as measure of the rising closeness to the urban nuclei. The repetition of wildfires is used as a quantitative measurement by adding the number of all different wildfires officially recognized occurring during the studied period. The results show that higher severity and repetition lead to less population and a later possible recovery. There are around 260 less inhabitants on average after at least one severe wildfire (around 10-510 less residents with 95% confidence interval). This finding suggests that, as it is also the case of other types of shocks, the effects of wildfires on the urban structure are permanent when they are large enough. Policy implications include a better education and sensitization on the environmental care, not building in wildfire-prone areas and improved alert systems. A better human-nature symbiosis is needed (for instance, employing extensive animal farms for cleaning the grass) for preventing fires.