Big fires have blazed across the Southwest before, but this year may mark the worst fire season in several states’ histories. Since January, some 11,000 wildfires have burned more than 3 million acres in Texas, blazes have torched nearly 1 million Arizona acres—including the state record-setting 522,642-acre Wallow Fire—and firefighters are currently still battling New Mexico’s Las Conchas fire, which has consumed more than 146,000 acres.
Years of fire suppression and today’s warmer, drier climate have spawned a new breed of furiously intense wildfires that can be nearly impossible to put out. In the current issue of Audubon, journalist Daniel Glick delves into the heated topic, and explores whether there’s any way to control these megafires.
From “The Perfect Firestorm”:
|At the Rocky Mountain Research Station’s Fire Sciences Lab in Missoula, Montana, chemists, physicists, fire behavior analysts, ecologists, life scientists, and engineers gather in a cavernous combustion chamber, playing with fire. Stands of metal are draped with what looks like wooden tinsel, made from shredded aspens. The four-foot-high “trees” stick out of an adjustable platform that’s four feet wide and 24 feet long, and can be tilted to mimic a section of the 25-degree south-facing slope of a ponderosa pine forest or the steeper high-alpine terrain of a spruce–fir forest. A huge exhaust hood with smoke sensors hovers over the pad. The acrid taste of decades of smoke permeates the room like a constant reminder of fire’s enduring impact.
Situated around the room, heat sensors and infrared and video cameras await ignition of the “forest.” Researchers hover behind instruments and laptops, their monitors shielded with the same silver material that firefighters use for protection. In an adjacent room, engineers dial in the prescribed temperature and humidity, preparing the combustion chamber for a really good mock conflagration.
Then, with the help of a little alcohol and a spark, the fire begins. Senior scientist and fire behavior expert Jack Cohen practically glows with pleasure as the shredded wood burns, licking the “trees” and climbing up the slope. This particular experiment is designed to give the team a better handle on how crown fires—the big, tree-to-tree events that make for such spectacular TV—spread. The multibillion-dollar national wildfire debate is only becoming more complicated, and the stakes higher.
During the past two decades record-setting blazes have occurred around the world, from Russia to Indonesia, Alaska to Brazil. These “megafires” exceed all efforts to control them, says Jerry Williams, who retired as the U.S. Forest Service’s top fire manager in 2005 and is now a Missoula-based fire adviser. Some of the blazes burn through more than a million acres. Embers launched from crown fire flames can reach two and a half times as high as the burning tree, starting fires up to two miles ahead of the fire front. Flaming debris can strike planes, grounding tanker pilots.
U.S. policy has pitted a deeply ingrained institutional belief that some wildfires can and should be “fought” against a scientific consensus that they are ecologically indispensable. Global warming has kindled the debate further because it has created both hotter and drier conditions in many places. In addition, a legacy of all-too-successful suppression means that many forests now contain huge “fuel stores” of woody debris that periodic fires used to eliminate. Add the fact that droves of people have moved into fire-prone areas, and you have an increasingly combustible mix of policy and ecology. “Megafires are signaling a new era in fire and land-use management,” says Williams.