Understanding Wildfires

By Maddie Veneziano, November 30, 2018
Associate professor Jake Brenner discusses California’s deadly forest fire season.
Wild fire in the distance at dusk

Associate professor Jake Brenner says increased development near fire-prone ecosystems in California has put more people at risk from wildfires.

(Photo by Erin Donalson)

The 2018 wildfire season has devastated California, burning over 1.6 million acres of land, costing almost $3 billion in damages, and taking dozens of lives. On Nov. 25, the Camp Fire, which was the most destructive and deadliest wildfire in the state’s history, was announced as 100 percent contained.

Jake Brenner is an associate professor in the Department of Environmental Studies and Sciences and faculty manager of the Ithaca College Natural Lands. He has worked on a wildland fire crew for the U.S. Forest Service in Nebraska and researched potential wildfire impacts in Arizona and Mexico. IC News asked Brenner why there has been an increase in catastrophic fires, what can be done to protect communities from future devastation, and how the environment will be impacted.

IC NEWS: Why were the recent forest fires in California so devastating?

BRENNER: There are three major reasons why the fires in California — like many others in the recent past — have been especially devastating. First is that people are increasingly putting themselves in fire’s way. Suburban and exurban residential development is encroaching on fire-prone ecosystems. In other words, the wildland-urban interface is becoming more densely settled.

Second, the nature of wildfire itself has changed. This owes largely to a century-long policy of fire prevention on federal, state and municipal lands. In a fire-adapted ecosystem, small burns are normal and they occur regularly. By preventing these burns, fuels build up that carry flames from forest floor to canopy. This fuel build-up has changed wildfire dynamics from relatively frequent, but modest, fires on the forest floor to infrequent, but catastrophic, fires in the forest canopy.

Finally, the natural fire dynamics that we have altered are also greatly influenced by climate change. In the American West, this means more frequent, longer and more severe droughts. Microclimatic conditions play a significant role in fire dynamics.

These things — along with several other secondary factors — are working together to overtax society's ability to put out wildfires before they exact high tolls in human life and property.

“Rhetoric of forest management has been used for several decades to rationalize the removal of the largest, oldest trees from the nation’s forests. This is not the kind of fuel reduction or thinning that most foresters agree would mitigate wildfire.”

Associate professor Jake Brenner

IC NEWS: It seems like these events are occurring more frequently in California. Why is that?

BRENNER: The general frequency of fire in fire-dependent ecosystems is not known to be greater now than in centuries past. What has increased is the incidence of catastrophic fires. Until recently, normally occurring minor fires had been all but eliminated.

IC NEWS: How can forest management be used to safeguard against wildfires?

BRENNER: Many things can be done, ranging from prescribed burns that mimic historical fire regimes, to clearing fuels from the forest floor, to mitigating climate change. All of these are consistent with current best practices in the forestry profession.

It’s important, however, not to be fooled by simplistic and ill-informed political rhetoric about forest management. Rhetoric of forest management has been used for several decades to rationalize the removal of the largest, oldest trees from the nation’s forests. This is not the kind of fuel reduction or thinning that most foresters agree would mitigate wildfire. In fact, misguided logging in the 19th century created the kind of fuel build-up that causes catastrophic wildfire.

A sign with "Smokey the Bear" warning about the extreme risk of forest fire

A sign at a California park warns visitors about the risk of forest fire.

(Photo by Jospeh Sohm)

IC NEWS: How do wildfires affect the environment?

BRENNER: In the California wildfires, we are confronting local air quality problems.  On the ground, different ecosystems behave differently. My research in the Sonoran Desert a system that did not evolve with fire and is highly vulnerable to it addressed the potential for complete landscape transformation because of fire. There, a desert with cactus and shrubs can turn into a savanna with grasses and small trees. Other systems, such as ponderosa pine forest, eventually return to their regular evolutionary fire regime. Every place is different depending on changing environmental conditions and human activities.

IC NEWS: What can be done when rebuilding to protect communities from future fires?

BRENNER: Building resilience against wildfire must be a multi-pronged approach. There’s a structural or engineering dimension that involves building with fire-resistant materials and maintaining an unburnable defensible space between buildings and surrounding vegetation. There’s an equally important behavioral dimension, including simple “Smokey the Bear” stuff like putting out campfires, but also more fundamental decisions like not building homes in fire-dependent ecosystems. Tying these together is a policy dimension, which can stipulate building codes and zoning rules, and also incentivize or regulate day-to-day behavior.

This interview has been edited for length and clarity.