Human-sparked wildfires are more destructive than those caused by nature

A firefighter battles the Ponderosa Fire east of Oroville, California, U.S. August 29, 2017. REUTERS/Noah Berger TPX IMAGES OF THE DAY - RC1361FC84E0

By / Tess Joosse

A wayward smoke bomb from a gender reveal party sparked a major blaze near Los Angeles in September, just one of many recent wildfires ignited by people. Now, an analysis of high-resolution satellite data from hundreds of California wildfires shows human-caused blazes spread much faster and kill more trees than ones ignited by lightning.

The findings highlight how fires that start differently can behave in distinct ways, with effects far beyond the amount of land torched, says Sean Parks, a fire ecologist with the Rocky Mountain Research Station’s Aldo Leopold Wilderness Research Institute, who was not involved with the study. “This focus on high severity rather than just area burned is important.”