You won't see Rob Sohlberg sweating over firebreaks in some remote Wyoming forest this week. But the University of Maryland geographer is helping fight blazes out West all the same.
Sohlberg is part of a small team of scientists at College Park and NASA's Goddard Space Flight Center in Greenbelt who are attacking wildfires not with pick and shovel but with a satellite.
This isn't the first time firefighters have turned to the skies for help battling blazes on the ground. For years they've relied on a hodge-podge of airplanes, helicopters and crews on the forest floor to map out wildfires. But that has drawbacks. There can be hundreds of flare-ups a day during the height of fire season, making it nearly impossible to catch them all.
"What it doesn't give is the consistency you get with a satellite pass," Sohlberg says. "Some of these areas are also quite remote, so you can't even get out there."
That's why Sohlberg and his colleagues have turned to Terra, a school bus-size satellite orbiting 438 miles up. The satellite, combined with fire-sniffing software, is giving wildfire battle planners the most detailed look ever at how fire is scorching the Earth this season in the United States.
On board the $1.3 billion spacecraft is a fire-detection instrument called MODIS, or Moderate-resolution Imaging Spectroradiometer. Sweeping the United Sates twice a day - in the morning and after dark - MODIS measures radiation reflecting off the surface of the Earth. As the readings reach PCs in the geography department at College Park and Goddard, a sophisticated computer algorithm sifts them for signs of flame.
"It's not that difficult to detect the fires," says Louis Giglio, a physicist at the National Aeronautics and Space Administration's Goddard center who helped write the fire-detection software. "The real problem is rejecting stuff that isn't fire."
At night, false alarms are rare and fires "look like stars" to MODIS, Giglio says. In the daytime, the sun can play tricks on the satellite. A reflection of sunlight off a lake or river can look like a fire. So can drought-stricken soil.
"Even some guy's shed in his back yard with a tin roof can fool you," says Giglio, who designed the software to weed out phony fires.
Under ideal conditions, the satellite can spot blazes as small as 20 feet by 20 feet, Giglio says. He said he hopes to refine the software so it can pinpoint even smaller ones. "Some guy's barbecue in his back yard, right now we couldn't see that," he says.
Once the automated fire-spotting software has run, the data is electronically shuttled to the U.S. Forest Service's Remote Sensing Applications Center in Salt Lake City, where scientists digitally embellish the emerging map with city names, state lines, topographic indicators and the colorful designations of this season's wildfires, which include Burnt, Falcon, Gridley, Icicle Complex, Sleepy Complex, Taco, Trough and White.
Although scientists elsewhere have been using Terra to study everything from global warming to deforestation since shortly after the satellite's launch in December 1999, the Forest Service began using it only in June. MODIS' fire-sensor readings, for reasons that are not clear, were languishing in digital cold storage inside various federal agencies for months before anybody analyzed them.
"The Forest Service doesn't have time to wait for that," says Sohlberg, who helped create the system that gets fresh readings to firefighters every 24 hours. "Data that's more than a day old is basically useless." The strategists at the Forest Service who decide where to deploy a limited supply of men, women and machines are eagerly digging in.
"It has made it much easier for me to quickly find out where the fires are," says Rick Ochoa, a meteorologist at the National Interagency Fire Center in Boise, Idaho, headquarters for the battle against the blazes out West.
On the MODIS map, hot spots glow crimson. Smoldering regions show up in paler tones. With a glance, "I can see patterns," says Ochoa, who looks for things such as whether fires are converging on a town or clawing their way uphill or down (important because fire tends to travel faster uphill).
MODIS, says Ochoa, is just one of the high-tech tools at his disposal in the evolving business of fighting fires. Other satellites such as Landsat, for example, can determine what type of vegetation grows in a particular spot and how old it is - both of which offer clues to the behavior of wildfires.
"We're always looking for where the next problems will be," Ochoa says.
The scientists sitting in air-conditioned offices in Maryland say they are thrilled that the project has given them a chance to lend a hand to smoke-jumpers and others on the front lines.
"It does feel good," Giglio says. "Although the guys with the shovels are the ones doing the real work."
