A New Era in Charting Wildfires in Alaska

McGRATH, Alaska —  The Cessna 208 Caravan circled the charred landscape for a closer look at lingering plumes of smoke. Sketchy reports had an old cabin burning at this particular spot during a wildfire in Alaska’s western interior.

“I’d like to find some trace to confirm it,” Dane Crowley said as the single-engine plane passed a small smoldering rim of the Colorado Creek fire about 245 miles northwest of Anchorage. A dark smudge stood out among the patches of black spruce that remained standing. Could this be what was left of the cabin?

Guided by the aircraft’s global positioning system, Crowley noted the location and marked it on a map he’d been developing for days as a fire-detection specialist with the state Division of Forestry.

Each fire season, such maps are created from flyovers in small planes and helicopters. They document Alaska wildfires and help fire managers develop combat strategies for ground and air crews.

Sometimes air crews use portable infrared equipment to identify hot spots. But for the most part, mapping Alaska wildfires depends more on experience and observations than on fancy instruments.

“It may be low tech, but it’s not low skill,” said Andy Williams with the Alaska Interagency Coordination Center. “It takes a certain amount of ability to read maps, recognize terrain features and judge fire behavior to accurately map a fire.”

Crowley, a 12-year state firefighter, maps interior wildfires, including the one at Colorado Creek and the 132,000-acre Vinasale fire near McGrath.

The Vinasale fire was accidentally started in late May by state biologists using firecracker shotgun shells to scare off an aggressive moose.

While Crowley is not in direct combat with Alaska’s wildfires, he considers the work just as crucial.

“If I blow this job, it makes it difficult for the people on the ground,” he said during an earlier flyover in the Caravan.

Soaring 2,500 feet over the vast region, Crowley was on the lookout for smoke, flames and burned structures, including the smudge at Colorado Creek that ground crews later confirmed was the remains of a cabin. Crowley knew the layout well and recognized where fires were advancing or dying out.

Once in a while he noted an area worth checking out and asked pilot Bryce Alber to circleagain.

On this day, the fires looked mostly dormant, except for occasional smoke and smoldering lines. But shifting weather can recharge fires, which tend to burn in mosaic patterns, leaving behind spotty expanses of live trees. That’s why it’s so crucial to monitor fires, whether or not they are being fought, fire officials said.

Crowley pointed out a large cumulus cloud hovering over a smoky area. “It’s a convective cloud, indicative of lightning,” he said. “That’s a pretty big cell there, at least 10,000 feet in height. A cloud like that hangs down over an active fire and creates wind that stirs things up.”

Back at the McGrath base camp, Crowley documented each of the nine fires monitored that day. The reports and updated maps are stored in files that are available to crews. “I include information I would want to know as a firefighter,” he said.

That information may include the obvious, such as latitude and longitude, weather conditions and the kind of vegetation being burned. Crowley also notes wind speed and direction, topography and natural barriers like rivers as well as the fire’s behavior -- whether it’s smoldering, creeping, crowning or flaming.

“We’re building on knowledge every day,” Crowley said. “This lets you really see the changes.”

Sometimes the information is added to maps produced by infrared scanners. Infrared is capable of tracking hot spots even through dense smoke, but it has limits. It can’t see through clouds, rain or extreme humidity. And it picks up terrain features better in the dark, said Jose Lopez, an electronics technician. “The clouds were a constant challenge in Alaska,” he said. “And it never really got dark.”

Another challenge in Alaska is developing computer fire prediction and mapping technologies effective for remote wildfires. Currently the Division of Forestry teams with local governments to calculate risk factors and forecast the likely path of fires.

“The firefighting community is in transition in using some of these newer tools,” he said. “We’re seeing almost an explosion. I think the old days of sketching maps with crude reference points is going away.”