Experts: 'Something Bigger is Going on' with Wildfires

Oct. 6, 2013
Science is connecting hotter, bigger fires and a longer, more intense fire season with changes in the climate.

Oct. 06--Firefighters say they've never seen fires burn the way they did in 2013.

That sentiment has been heard before. In 1988, 2000 and 2007, fires grew in size and ferocity across the American West, exceeding the experience and knowledge of firefighters and scientists alike.

This year, fire returned to places that had burned before: Colorado Springs, Pine, Ketchum, Yellowstone and Yosemite. The fires of 2013 burned through many of our previous ideas about how we can live with fire.

What's different this time? Science is connecting hotter, bigger fires and a longer, more intense fire season with changes in the climate.

--Long before fire season, the mountains are undergoing change. Winters are warmer, meaning smaller snowpacks that melt sooner. That means runoff ends earlier and the forests dry out earlier; fire season starts earlier and lasts longer. When summer arrives, hotter, drier Julys get fires started earlier and bigger. In August and September, low humidity, wind and other unstable atmospheric conditions create erratic burning that overwhelms the best prevention and firefighting tactics.

--During fire season, fire bosses are changing tactics. They might pull their crews out of the way of extreme fires and evacuate communities more promptly. The bosses work to "herd" fires into previously burned areas, making them easier and cheaper to fight. Communities can clear brush and other fuels away from homes, providing firefighters with "defensible space." But those measures have to be regularly renewed. In some rural residential areas, topography and fuel still make them nearly indefensible, as the Fall Creek area west of Pine found this summer. And once homes in the "urban interface" do start burning, wildland firefighters have to adopt urban tactics.

--After the fires, forests face tougher conditions in which to recover. Fires in parts of the Northern Rockies now burn so frequently or so hot that the trees don't get a chance to grow big enough to produce seeds for the next generation. Even in forests with enough trees, hotter, drier conditions cause fewer seeds to germinate and more seedlings to die.

Some won't be forests again: Sun-baked south slopes are turning from forests to brush, as can be seen near the Lowman-area fires of 1989. Over time, more low-elevation forests could return to brush and grasslands. Low-elevation species such as ponderosa pines will move higher and farther north to cooler, moister conditions; high-elevation species such as Douglas firs will recede as fire frequency increases.

The bottom line: Nature is adapting to changing conditions. The fires of 2013 taught us that humans have to adapt to new realities about fires and forests, too. Our practices and our developments were designed for conditions that no longer exist.

Stephen Pyne, noted fire historian from Arizona State University, says we can't "solve" the fire problem in any technical sense because it will always be changing.

"Our task is not to fix what can't be fixed," he wrote recently, "but to pass between the flames as best we can."

GHOST TREES

Long, straight piles of ash covered the hillside of Greenhorn Gulch near Hailey in August days after the Beaver Creek Fire roared into the exclusive neighborhood.

These ghost trees showed how hot the fire got on its two-mile run through the living forest. Forty miles west, similar ash piles covered the hillsides around Fall Creek, where the Elk Complex burned more than 100,000 acres in three days.

Collette Boguslawski pointed to the melted pile of metal that was part of the roof of her Fall Creek home, which was consumed even though it was surrounded by a wide, fuel-free clearing.

"When you have over 1,000-degree temperatures, it doesn't matter what you do," she said.

In California this summer, Gus Smith saw ghost trees in the path of the Rim Fire that burned through an area near Yosemite National Park. The fire followed the scar of a 1996 fire that left brush and big dead trees on the ground that have held their moisture for hundreds of years in the relatively wet conditions of the High Sierra.

This year, they turned to ash.

"Really big logs take a really long time to dry out," said Smith, fire ecologist at Yosemite National Park. "They are indicators that something bigger is going on."

Idaho's Elk Complex burned through trees in an area that had just been logged and through thousands of acres of state forest land that had been aggressively managed for 20 years. In the moister Sierra forest, Smith watched the Rim Fire burn through foothills with four different forest types up to the high-elevation lodgepole pine.

"If four different types of forest wouldn't stop the fire, no fuel treatment would," Smith said.

WHAT WE'VE LEARNED FROM 25 YEARS OF FIRE

Fire scientists say that the West's ecosystems evolved with fire. We can't stop it. When we do temporarily, we end up triggering the even bigger fires we see today.

In Southwest Idaho, most of the landscape has burned in the past 30 years. More than 56 percent of the Boise National Forest has burned since 1985 and 71 percent of the Payette, according to Forest Service numbers compiled by the Idaho Conservation League.

The forests have grown back where many of the older fires were, presenting land managers with new challenges. They not only have to mechanically thin and prescribe-burn to lessen fire risk in unburned areas, they also have to do the same with forests that have grown back from earlier fires.

"If we do not do these treatments outside of the fire season, it will be impossible to catch up," said Paul Bryant, Boise National Forest resource and planning officer.

Some previously burned areas are burning again on their own. The Pony Fire burned young ponderosa pines that were growing back after the Foothills Fire of 1992. Foresters are watching whether the forest will shift to brush.

On the Elk Complex, the fire burned so extreme in many areas that all of the seed source is gone, said Boise Forest silviculturist Ray Eklund. He's determining now where the agency should try to replant ponderosas, where it can expect natural regeneration and where it should let the area change to rangeland.

He looks back to the 1989 Lowman Fire area, where replantings died within a couple of years. Foresters planted ponderosa again on the north slopes, which have wetter soils. Many survived.

But the south slopes have now largely converted to brush.

'CHANGING FASTER'

Eklund's decisions are based both on ecology and economics: With tight budgets, there isn't the money to replant every acre when many trees won't survive.

"We have to be more judicious where we plant," Eklund said.

Monica Turner, a landscape ecology professor at the University of Wisconsin, has studied the forests of Yellowstone National Park since 1988. She has seen reduced regeneration where fires occur before the trees grow big enough to produce sufficient seed and where post-fire drought prevents germination.

She hopes to expand her studies to the entire Northern Rockies to determine how climate change will transform the forests. Right now she and agency scientists have little data on which to make predictions for the future.

Overall, she expects the brush and rangelands to replace some of the region's forests. She expects ponderosa pine to replace Douglas fir in the higher elevations as the frequency of fires there increases.

"Aspen may be one species that benefits from more frequent fires," Turner said. "I think we will see more areas of no forest or areas turn to a woodland scrubland. That doesn't mean we'll lose our native species or our wildlife."

Boise State University geomorphologist Jen Pierce has been studying the changes in the ponderosa pine forests in Southwest Idaho historically and agrees with Turner on the trend.

"They always have been adapting to change," Pierce said. "They're just changing faster."

TIME FOR HUMANS TO ADAPT

Gov. Butch Otter sparked a debate in August when he said that the Fall Creek area burned in the Elk Complex was "an almost indefensible area."

Since the 1980s, firefighters have urged residents to make their homes safer. Fire science now shows that most homes are ignited by flying embers thrown as far as a mile and a half ahead of a crown fire, or when the ground fire reaches brush and trees within 100 feet of buildings.

The homes themselves burn especially hot, but the trees nearby are often left with their green canopies intact.

Research has shown that fires can be fought within the communities, and that raging fires on public lands don't need to be stopped in the wilderness to protect private property. But when you get hundreds of homes threatened, there just aren't enough firefighters to save them all.

And when crown fires are especially extreme, the fuel thick, the topography steep and the wind blowing, it becomes too dangerous to try to protect some areas, Forest Service officials say.

Pierce, who owns a cabin in the heavily forested Big Hole Mountains in Teton County, said knowing what she does has prepared her in a different way.

"The best thing we can do to mitigate for fire damage is make sure our insurance is up to date," Pierce said. "Adapting to climate change is just accepting our house may burn down."

Rocky Barker: 377-6484

Copyright 2013 - The Idaho Statesman

Voice Your Opinion!

To join the conversation, and become an exclusive member of Firehouse, create an account today!