MOSCOW, Idaho – A new study from the University of Idaho claims that humans are responsible for half of northwest wildfires.

According to wildfire records from 1992-2012, humans started 84 percent of all wildfires nationwide. In northwestern states – including Idaho, Washington, Oregon and Montana – humans started roughly half of all wildfires.

University of Idaho researcher John Abatzoglou said the numbers show the importance of the governments and citizens in the Northwest states working to reduce human-started fires.

Researchers concluded that humans are expanding the “fire niche;” bringing fire to areas and environmental conditions where lighting does not start fires naturally. Researchers included arson, smoking, railroads, fireworks, children playing with fire, campfires and burning debris among the ways humans start wildfires. Vehicles sparks and downed power lines can also start fires in remote areas.

“We saw significant increases in the numbers of large, human-started fires over time, especially in the spring,” said Bethany Bradley of the University of Massachusetts Amherst, who assisted with the study. “I think that’s interesting, and scary, because it suggests that as spring seasons get warmer and earlier due to climate change, human ignitions are putting us at increasing risk of some of the largest, most damaging wildfires.”

Idaho had the largest burned area of any state in the lower 48 between 1992-2012. Only 31 percent of fires were human-caused.

In Oregon, humans were responsible for starting 48 percent of fires. Humans were accountable for 53 percent of fires in Montana and 70 percent of Washington fires.

According to a release from the University of Idaho, the Pacific Northwest’s lower numbers are due to population density. In Idaho, there are millions of acres of uninhabited land.

“The hopeful news here is that we could, in theory, reduce human-started wildfires in the medium term,” said Jennifer Balch of the University of Colorado-Boulder. “But at the same time, we also need to focus on living more sustainably with fire by shifting the human contribution to ignitions to more controlled, well-managed burns.”