Air pollution-fire weather interaction in diverse regions

Wildfires pose a substantial threat to human lives, destroy infrastructure, disrupt economic activity, and damage ecosystem services. Weather and climate conditions, including air temperature, humidity, wind, and precipitation, play crucial roles in determining the intensity and persistence of wildfires, as well as the dispersion and transport of smoke plumes. In turn, aerosols emitted from biomass burning are capable of influencing meteorology via aerosol-radiation interaction or aerosol-cloud interaction. However, there has been limited attention paid to the intricate interplay between smoke aerosol pollution, fire weather, and wildfire emissions. Our studies highlight the significance of synoptic-scale feedback in driving extreme wildfires across diverse fire-prone landscapes, including the United States, southeastern Asia, and even the Siberian region. We found that meteorological feedback induced by smoke aerosols can modify near-surface wind speed, air dryness, and rainfall and thus worsen air pollution by enhancing wildfire emissions and weakening dispersion. The intricate interactions among wildfires, smoke aerosol, and fire weather form a positive feedback loop that substantially increases air pollution exposure.