So far, the Rim Fire has been California’s worst wildfire for 2013, scorching more than a quarter-million acres in and around Yosemite and destroying more than 100 homes. Take it as a harbinger.
As Cal professor of fire science Scott Stephens and his co-authors noted in a recent paper in the journal Science, climate change will cause more and hotter wildfires in North America, Australia, Russia and the Mediterranean Basin. That’s an especially dire forecast for the American West, where the massive growth of the “urban-wildland interface”—housing developments in forested areas—has made the jobs of firefighters more difficult and expensive, and placed human beings and their properties at increasing risk.
Moreover, these fires—supercharged by climate change—are altering the composition of our wildlands, turning large tracts of coniferous forests into hardwood savanna or grasslands.
“This is already happening to a significant degree in the American Southwest,” Stephens tells us. “The Southwest is a barometer for the changes coming down on us. Craig Allen, a research ecologist with the U.S. Geologic Survey in New Mexico, has identified huge areas that have repeatedly burned in the last 10 years or so. These were formerly ponderosa pine forests, and now they’re grasslands—and in all probability, they’re going to stay that way. The (pine) seed sources have been completely destroyed, and the region will probably become hotter and drier as climate change progresses. We’re seeing changes, massive changes, before our eyes.”
Moreover, climate change seems to be extending the wildfire season in the West. Typically, western forests are most vulnerable to fire from late summer through early fall. But in recent years, the woods often start burning sooner—late spring, in the case of the Southwest—with fire danger remaining high until the beginning of winter, or later in the case of drought.
California is at the point of this burning spear. For 2013 to date, state-funded firefighters already have squelched more than 6,000 wildfires, or about 1,600 more than usual.
“Southern California is actually at its highest fire danger right now,” says Stephens. “Fuels are extremely dry, and you could see some very destructive fires once the Santa Ana winds start blowing.”
The risks of unrelenting wildfire are manifold. The threats to property and wildland ecosystems are obvious, but there may also be broad-based hazards to human health. A recent study from the Natural Resources Defense Council noted the smoke from wildland blazes in 2011 affected areas 50 times greater than the total acreage burned, ultimately subjecting 212 million people—fully-two thirds of the U.S. population—to elevated air pollution, including the fine particulates associated with pulmonary disease.
Can anything be done to alter this trajectory? Stephens assures us a change in fire policy would be salutary for both people and forests. But such a shift will require political will and lots of money.
“Maybe the most daunting question here is how we fund fire suppression in the interface,” Stephens says. “Local jurisdictions determine the growth of interface through zoning—but they’re usually not on the hook for fire suppression costs. That falls to the state and federal governments. So in effect, the taxpayers in general subsidize fire protection for interface construction. If the local jurisdictions and homeowners had greater liability for those costs, I think you could get a better handle on the problem.”
Not that we aren’t spending a lot of money for wildfire; we are. Stephens noted federal expenditures for wildfire suppression hit a new record this year—$3 billion. But much if not most of that went to protecting structures in interface zones.
“The (U.S.) Forest Service had to pull money from research and forest restoration for suppression,” says Stephens.
And that gets back to the crux of the problem, he adds: We shouldn’t be expending lavish quantities of taxpayer dollars to protect homes in the woods. Interface growth is skewing the role of wildfire fighters, forcing them to function as urban firefighters. That means their mission has changed from protecting forests, wildlife and watersheds – so-called “ecosystem services”—to protecting property.
“You saw it on the Rim Fire,” Stephens says. “All the suppression resources were shifted to the west side of the fire, where all the development was. So the forests in the rest of area were hit really hard.”
Nor is the Yosemite area an outlier. Interface growth is “exploding” throughout the West, Stephen says, and “it’s an especially crucial issue for California, a state that already bears a considerable portion of the nation’s wildfire suppression costs: “That price tag is going to keep going up unless we change things and get a handle on interface growth.”
Policy changes also are needed in wilderness management, Stephens says: Forests need to be “fireproofed” by the regular control of fuels through prescription burning and “mechanical” means: thinning trees and brush.
This is particularly important for forests that have evolved with “high frequency, low-to-moderate severity” fire regimes, such as the ponderosa pine and Jeffrey pine forests of the Sierra. Historically, these forests experienced regular burning—either from lightning or native inhabitants. These low-intensity blazes consumed all the dead fuels, resulting in forests with large, widely-spaced trees that were resistant to catastrophic fire.
“I recently looked at the Rim Fire burn, specifically an area that had some beautiful old-growth timber,” Stephens says. “Most of the stands were destroyed. It was very disturbing. If there had been any (fuels) treatment in those areas, I really think those trees would’ve been spared.”
Wildfire suppression still operates on the principal that was established in the 1930s and 1940s, when the object was to snuff out all fires as quickly as possible. This, in turn, has led to a massive accumulation of fuels in our wilderness areas. Until these policies change, Stephens warns, our forests will continue to go up in smoke—and climate change will only insure a faster burn rate.
“It’s a cycle we need to break,” Stephens says. “It won’t be easy. Restorative treatments, including fuel control, are expensive. But we need to find a way to introduce them on a large scale or the frequency and severity of our wildfires will only increase.”
Some modest—very modest—progress is occurring on that front, says Stephens: He notes that U.S. Rep. John Garamendi, D-Walnut Grove, is working on a bill to increase funding for forest restoration: “His office asked me for a link to (the Science) article, so there’s at least some awareness of the issue.”
Still, the core message isn’t getting through: Put the onus for property protection on those people who choose to live within interface zones, and reserve scant public dollars for forest restoration. Stephens says recent reaction to an idea by Cal researchers for replacing fire lookouts with geosynchronous satellites to detect wildfires is an example of not seeing the forest for the trees. Stephens and Cal physicist Carl Pennypacker and remote sensing authority Maggi Kelly outlined the details of the plan in the latest issue of the journal Remote Sensing.
“Some of the responses have been to the effect, ‘Oh, this is will be a great suppression tool,” Stephens says. “That’s not the road we want to go down. A satellite system like this could identify lightning strikes that could ultimately develop into destructive fires, and provide more timely updates for evacuations—so in that sense it can be seen as a way to improve public safety. But its primary purpose is informational, not bolstering suppression efforts. Again, we can’t keep pushing fire suppression at the expense of forest restoration. It’s unsustainable.”