Climate change has inexorably stacked the deck in favor of bigger and more intense fires across the American West over the past few decades, science has incontrovertibly shown. Increasing heat, changing rain and snow patterns, shifts in plant communities, and other climate-related changes have vastly increased the likelihood that fires will start more often and burn more intensely and widely than they have in the past.

The scale and intensity of the wildfires burning across the western U.S. right now is “staggering,” says Philip Higuera, a wildfire scientist and paleoecologist at the University of Montana. More than five million acres have already burned this year—and much more may be yet to come.

Other factors also hike fire risk, like forest management