The Perfect Firestorm
Welcome to the new era of "megafires," which rage with such intensity that no human force can put them out. Their main causes, climate change and fire suppression, are fueling a heated debate about how to stop them.
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.
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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.
As the biggest intensify and cannot be controlled by any amount of firefighting, they will surely challenge every conception we've had in our ageless history with fire.
In the fall of 1987 Williams was in Happy Camp, California, working a lightning fire spreading through coastal Douglas fir forest, which is a wetter forest that doesn't typically burn big. As a Forest Service branch director, he kept receiving updates about several fire complexes from northern California to southern Oregon that were growing--and fast. Williams watched the situation reports, dumbstruck by the scale. "This is the biggest thing we've ever seen," he recalls saying about fires in the Siskiyou and Klamath national forests that came to be known as The Siege of 1987 and burned 640,000 acres. At the time he thought, "We'll never see anything like this again."
Boy, was he wrong. The following year the Yellowstone fire consumed nearly 1.5 million acres and the national news for weeks. Since then many U.S. states have recorded their biggest fires ever. The term megafire started to attract attention. Experts wondered if "fighting" these colossal fires wasn't about as effective as dropping DC-10 tanker loads of $100 bills into the flames. More than three million acres have burned each year since 1999--and a 10-million-acre year is almost certainly on the horizon. As the cost of firefighting crossed the billion-dollar mark every year since 2002, another measure of "mega" began to catch policy makers' eyes: mega expensive. The money being thrown around to douse these fires has pretty much gone up in smoke--and more than 400 wildfire fighters have died since 1987.
Ironically, one of the main reasons we have such a perfect firestorm today is that we've been so good at suppressing fires over the past century. There are 10,000 or so U.S. wildlands fires every year, and firefighters put about 95 percent of them out early on. With manpower and a lucky turn of the weather, more are contained. But for about two percent of wildfires, no amount of retardant, fire lines, or Hotshots wielding Pulaskis have appreciable effect. Most firefighting money goes to this minority of massive fires. In 2008 the federal bill hit nearly $1.5 billion, forcing the Forest Service to cut back on other programs.