Wildfires across the western U.S. have increased over the last few decades, driven by a combination of climate, fuel buildup, and land management.
“And a lot of people project that that increase in the entire West is going to continue," said Jim Lutz, a professor in wildland resources at Utah State University. His latest study looks specifically at Utah, rather than the West as a whole.
“We recognize that Utah has unique vegetation types, and some of the drivers of fire are different in Utah," Lutz said. "So, we wanted to study what's going on in Utah, and we wanted to look at what's going on in each of the different vegetation types that Utah has.”
Instead of using complex climate models, the study examined every fire larger than 100 acres in Utah since the mid-1980s, comparing fire size and frequency to basic weather data.
“And so, what we found was that in a fire season, if we had a lot of hot days, more than 80 degrees Fahrenheit, we were more likely to have fires, and those fires were more likely to be bigger,” Lutz said.
The results really are as straightforward as that — in Utah, at least, and across all vegetation types, more days hotter than 80 degrees Fahrenheit means bigger and more frequent fires. But Lutz didn’t just look at the past.
“We used trend data from Utah weather stations to predict the number of hot days we are likely to have in the future, and there's more," he said. "So, because there's going to be more hot days projected in the future, there's also going to be more fire activity in the future.”
But Lutz emphasizes that these findings, though dire, can provide guidance.
“The sky is not falling here," he said. "This is something we can manage. If we know that we have risk and the risk is increasing, we can take action to mitigate that risk.”
You can read Lutz's study published in the journal Climate Change, read more about what this means for Utah in Utah State Today, and look at wildfire risk in your area using DNR's wildfire risk website.
