Early start, late finish, dry fuels mark second inflammatory year
Hot weather. Dry forests. Turbulent masses of unstable air that conjure upthunderstorms.
Lightning strikes the Fairbanks area in June. This season, bolt-caused fires are four times the average.
Mix these ingredients from Alaska’s changing climate and you produce a 2005 fire season that starts early, ends late and incinerates millions more acres than normal.
Lightning triggered more wildland fires this summer in Alaska than ever noted before, sparking one of the worst, longest running burns on record, according to state fire and federal fire officials.
Through Friday morning, 598 fires had scorched 3.8 million acres across the state, less than the record 6.7 million acres in 2004 but more than any previous year except 1957, said John See, the state’s regional fire manager for coastal Alaska.
“In the course of firefighting in this state, we’ve never had two challenging seasons back to back,” See said. “Never once.”
The driving force this year appears to be gobs of thunderstorms that repeatedly zapped crisp spruce forests and the tinder-dry vegetative mat covering the ground.
“We had a warmer spring and a longer warm summer, so we have a longer period of time with the opportunity for thunderstorms,” said fire weather meteorologist Sharon Alden, with the Alaska Interagency Coordination Center at Fort Wainwright near Fairbanks.
A sophisticated Bureau of Land Management detection system pinpointed about 135,000 cloud-to-ground lightning strikes in Alaska so far this season — more than three times the average number of strikes seen in recent years, Alden said.
As a result, lightning triggered at least 328 fires so far this season — about four times the average, See said. Previous totals ranged from 275 lightning-caused fires in 2004 to only 28 in 2001.
This recent, dramatic surge in lightning fires has alarmed and amazed fire officials, especially in the Southcentral region between the Kenai Peninsula and the Matanuska-Susitna area.
More than 1,000 lightning strikes peppered the beetle-killed forests of the Kenai Peninsula, triggering 15 to 20 fires, officials said.
“There are some years that we don’t have any lightning starts at all,” said Ric Plate, state fire management officer for the Kenai-Kodiak areas. “This year we had more lightning-caused fires than we had in the past 10 years.”
Lightning fires often ignite in remote areas or rugged terrain, and that presented a challenge on the Kenai, Plate said. Managers previously expected most fires to be caused by people relatively close to roads.
One cooling breath of news: This summer marked the first time that thunderstorms out-sparked people. Only 267 fires were traced to human activity, the lowest number since 1980, See said. Compare that to the 426 human-caused fires in 2004.
“I think we are doing some things right in terms of prevention and working with the public,” See said. “The public probably deserves kudos for their cooperation.”
The simplest explanation for 2005’s big burn hinges on the weather.
“The climate really drives it all,” said Frank Cole, fire behavior specialist with the Coordination Center.
Alaska’s sunny spring dried out, or “cured,” trees, brush and other potential fuels, Cole said. While much of the state had normal or higher than normal snow, much of the pack basically evaporated into the air without soaking the ground. Thunderstorms followed. Rainfall was often sparse.
As a result, the season began early, with 38 wildland fires burning across the state by April 30. The total included a large fire outside Homer, caused by a sparking power line, that grew to 5,000 acres.
Many crews and expensive equipment were not ramped up yet, including an air tanker that could have dumped retardant on Homer’s Tracy Avenue fire in its first few days, See and other state fire managers said.
The state’s official fire season from May 1 to Sept. 30 clearly no longer defines the period when people should be careful and crews must be ready to respond, noted Lynn Wilcock, statewide fire operations forester with the Division of Forestry in Fairbanks. “Right now, we’re seeing that April is very much inside the fire season.”
By July, Alaska’s typical summer weather pattern brings a southwest flow from the North Pacific, delivering increasing rain and cloudy weather, See said. Fire season fizzles.
Not this year. About 1.8 million acres have been torched since Aug. 1, with 105 fires still burning Friday. And this is not new in 2005.
“From Aug. 1 to the end of the fire season, we’ve burned more than a million acres in three of the past four years,” See said.
He and other state officials say they’re now talking about the need to move up the statutory start of fire season, and whether the state needs to make sure equipment and crews are ready to respond earlier in the spring and later in the fall.
“We’ll definitely be looking at earlier starts or redefining that fire season,” Cole said. “Of course, who knows? It could be snowing in May next year. You never know what you’re going to get in the wonderful world of weather up here.”