Summer and fall are wildfire season across the western U.S. In recent years, wildfires have destroyed thousands of homes, forced hundreds of thousands of people to evacuate and exposed tens of millions to harmful smoke.
Wildfires are a natural disturbance for these regions, but when combined with climate change and housing growth in the wildland-urban interface – zones where development has spread into wild areas—they have become larger and more destructive.
To make matters worse, humans are responsible for starting almost all the wildfires in developed areas that threaten U.S. homes. In a newly published study, we show that through activities like debris burning, equipment use and arson, people ignited 97% of home-threatening wildfires in the wildland-urban interface between 1992 and 2015.