Drought, climate change, forest practices elevate Utah's wildfire risk

Drought could make this summer especially busy with wildfires, warn forest and climate researchers at Utah State University.

A changing climate is one significant factor in the forecast now and in future years.

So is the hazard created by modern forest management, said Michael Jenkins, associate professor in USU's Quinney College of Natural Resources. Aggressive management has been "essentially eliminated," and dry forest undergrowth has built up, turning parts of Utah into tinderboxes, he said.

"Forests today are in a much different state than they were 200 years ago when fires were more common," Jenkins said. "We have suppressed fires for 100 years, which has allowed fuels to build up, trees to get old, forests to decline and die."

Meanwhile, Utah is in the second year of drought in a six-year dry trend, based on broad patterns tracked at the Utah Climate Center. And, while precipitation has held steady in recent years, warming temperatures mean more of that precipitation is falling as rain instead of snow.

This timing shift is also important for water managers and others who rely on runoff to supply water for homes and farms, said State Climatologist Rob Gillies.

"If there is a lot of snow and the temperatures are relatively cool during the springtime, then the snow melts slowly through the soil," he said. "If you have a small amount of snow and then it rains, the soil becomes saturated very quickly and the rain just runs off."

The links between wildfire and climate also came up elsewhere on Tuesday.

Jennifer Marlon, associate research scientist at the Yale School of Forestry and Environmental Studies, told reporters that her research on 3,000 years of wildfires shows a strong correlation between wildfire, drought and warming. In fact, the tie is so robust, that temperature and precipitation can be used to predict wildfire.

"Generally, when you increase the temperature, you get more fire," she said, noting that longer seasons also contribute to the trend.

Meanwhile, on Capitol Hill in Washington, D.C., U.S. Forest Service Chief Tom Tidwell said in a statement to a Senate committee that his agency is facing increasingly extreme wildfires and challenges associated with the trend. He noted wildfires burn twice as many acres a year now as they did four decades ago.

"Last year, the fires were massive in size, coinciding with increased temperatures and early snow melt in the West," he said. "The largest issue we now face is how to adapt our management to anticipate climate-change impacts and to mitigate their potential effects."

According to the Forest Service, fire suppression costs now eat up almost half of the agency's budget, while fighting wildfires used just 13 percent of the budget in 1991. Meanwhile, the agency said its 10-year average cost for fighting fires has increased to more than $1 billion in 2010 and beyond.

fahys@sltrib.com

Twitter: @judyfutah