Climate change is a main driving force behind the huge uptick of dangerous wildfires the western U.S. has been experiencing during the last decade — and this year is no exception. In terms of total acreage burned, the eight worst wildfire seasons since 1960 have all occurred in the last 12 years.
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A Summer of Extremes: Confronting the Realities of Climate Change
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Warmer and drier conditions, coupled with a longer fire season, are causing bigger and hotter fires that are burning longer, causing more damage, and putting firefighters lives at risk. Dave Cleaves, climate change advisor to the chief of the U.S. Forest Service, confirmed at a recent UCS briefing that more extreme fire weather is leading to larger and more severe fires.
He also said that nearly half the Forest Service budget is now dedicated to suppressing and managing fires, preventing much needed funds from being deployed for important forest management priorities.
Costs of Wildfires Could Swallow U.S. Forest Service Budget
Economist Ray Rasker, CEO of Headwaters Economics, an independent non-profit based in Bozeman, Montana, noted that the cost of fire management to federal agencies is now three times what it was a decade ago. He said studies in Montana and California have shown that approximately a third of the costs of fighting fires are now for defending homes that have been built in dangerous, fire-prone areas.
A forest fire burning in Yellowstone. Photo: NPS
More and more houses are being built in the Wildland Urban Interface (WUI – the areas where private lands abut federal lands), draining the Forest Service budget and putting firefighters’ lives at risk to protect them. But with only 16 percent of the WUI already developed, and house-building and residential development picking up again after the recession, the costs and risks are growing all the time.
Rasker warned that the combination of larger, more intense fires that burn longer due to climate change and uncontrolled residential growth in the WUI would lead to exponential growth in fire management costs and eventually swamp the Forest Service’s budget.
Catastrophic Fire Seasons Likely to Increase and Their Impacts Worsen
At the same briefing, Anthony Westerling a fire researcher at the University of California, Merced, explained that the changes have been so rapid and noticeable in recent years because many western forests were already close to a threshold which warming conditions are pushing them over.
Climate is a crucial limiting factor in preventing forest fires. When conditions are cool and moist, fires don’t break out as much and they tend to burn less strongly. Westerling said that drier winters and a continuing warming trend are shifting the situation so that we are reaching a situation where most years will likely be as dry and as warm as they have ever been in the last century, making the risk of catastrophic fires an ever-present feature of our summers.
Further exacerbating the situation, said Craig D. Allen, an ecologist at the U.S. Geological Survey (USGS) Field Station at Bandelier National Monument in New Mexico, is that decades of active fire suppression in the West has prevented the smaller less intense surface fires that helped naturally thin forests across the west. This has caused many forests to grow denser and therefore more able to support the hotter and more intense crown fires that destroy complete stands and devastate thousands of acres at a time.
Changing fire dynamics and climate conditions are increasingly likely to result in some western forests failing to regenerate and being transformed into brush and grassland. Photo: Adam Markham.
According to Allen, there is extensive scientific evidence from tree rings and fire scars in western forests that there are more fires in warmer and drier years. With conditions now trending warmer and drier in the Southwest than anything that’s been observed over the last two centuries, and average temperatures probably higher than they’ve been for at least a thousand years, Allen thinks forest ecosystems may be reaching a tipping point in the region.
Some forests may never recover from major fires or dieback caused by drought and heat. There is a very real danger that much land that is now forested will eventually be transformed into shrub or dry grassland.
No Doubt About the Role of Climate Change
Forest Service veteran Cleaves said that over the last 20 years the environmental context of fires and forest disturbance have been changing rapidly. Fires, insect outbreaks and water stress are all being linked more closely by the common thread of climate change. “We are now completely certain that there is a climate signal in the fire activity,” he said at the UCS-organized press briefing.
And with the growing fire activity comes increasing costs. Not just those associated with preventing and suppressing fires, but also the costs of post-fire environmental impacts such as flooding and erosion, insurance claims, re-building, and restoration. The Waldo Canyon and Black Forest fires in Colorado in 2012 and 2013 together represented the most costly fires in the state’s history with more than $650 million in insurance claims.
A 2011 report from the Western Forestry Leadership Coalition analyzed the full costs for a series of major fires since 2000 and concluded that after-fire costs could rise to as much as 30 times the price tag for fire management suppression costs. For example, the Cerro Grande Fire, which spread from Bandelier National Monument in 2000, ultimately cost $970 million, only about $33 million of which was for suppression — most of the total went to reconstruction and restoration.
Urgent Actions Needed to Control Housing Development in High Risk Areas
The 2012 Pine Creek Fire in Montana burned more than 8,000 acres. In common with residents of the WUI across the West, homeowners are re-building in high risk zones. Photo: Adam Markham
At the UCS briefing, Ray Rasker, an economist specializing in forests and rural development, called for a national dialogue to find some innovative solutions to prevent fire costs from spiraling out of control and noted that it is the federal taxpayer that shoulders much of the burden of fire management.
Perhaps local governments which allow unbridled housing developments in forested areas and the homeowners who choose to live there should bear more of the costs? Should mortgages be available to people who build in high risk fire zones? Should local authorities be required to pay a larger share of fire prevention costs?
These and many more questions will grow in urgency as more and more forested lands in the West move towards the climate tipping point in a warming world.