Computer Model Holds Key to Wildfire Behavior

Article excerpt

LOS ALAMOS, N.M. -- For the last four years, scientists at Los Alamos National Laboratory have been crafting a supercomputer model capable of making highly accurate real-time predictions of the behavior of wildfires.

It was with a sense of irony, then, that researchers at the nuclear research facility were forced to flee their own offices this month as a runaway blaze roared through Los Alamos, torching hundreds of homes, incinerating thousands of acres of dry ponderosa pine and leaping through the treetops onto lab property.

"I was trying to figure the fire out, but I didn't have a laptop with me," admits Jim Bossert, the project's leader, who studied the recent wildfire movements the old-fashioned way -- from a window at his home outside Los Alamos, N.M.

Dealing with wildfires remains an inexact science. But at Los Alamos, which has reopened, and at fire research labs across the country, researchers are getting closer to being able to accurately predict the behavior of forest fires, largely by combining cutting-edge physics with age-old understanding of how weather, terrain and the forest itself affect blazes.

"A lot of the answer involves relying on computer modeling. There's no other effective way to do it," Bossert said.

Computer-assisted modeling of forest fires got its start in the late 1980s, when firefighters began using handheld calculators to input information about wind speed, humidity and forest fuels in an effort to guess how fast blazes might spread and how high the flames might grow.

Both pieces of information are key to deciding where to safely place firefighters to most effectively attack a blaze, according to Tom Zimmerman, a fire science expert with the National Park Service.

A fire with relatively small flames of up to 4 feet, for instance, can safely be fought head-on by crews with hand equipment, Zimmerman said. A blaze fronted by 8-foot flames requires heavy equipment, and a 12-footer means everybody needs to pull back and try a flank attack, or to create a firebreak well ahead of the blaze.

The original computer models, which took only a few variables into account, didn't amount to much more than a bit of mathematical help for fire captains. But "it was better than scratching your chin and trying to figure out what was going to happen," Zimmerman said. …