Below are excerpts from a couple of articles about the fact that wind and weather conditions drive all large wildfires.
From the Missoulian:
Larry Bradshaw was riding his motorcycle down U.S. Highway 12 on Monday afternoon when he noted the building smoke and stiffening winds.
It was an acute observation for a meteorologist who has worked at the U.S. Forest Service’s Fire Sciences Laboratory in Missoula since 1992, and still maintains the National Fire Danger Rating System.
Bradshaw tuned into the scanner a few hours later and listened as chaos unfolded ahead of the West Fork II fire, the blaze jumping the highway he’d ridden hours earlier before making a run east down the Lolo Creek Canyon.
“The winds were really strong out of the west,” said Bradshaw. “The inversion broke there earlier than it did in Missoula.”….
“It was the same recipe used on every fire – it’s dry and it’s windy,” said Finney. “We have a canyon situation and a couple fires low in the canyon. The fires have topography working in their favor – the canyon topography helping with the winds.”
The tools used by fire managers to predict the interaction of wind, topography, weather and fuel were developed here by the likes of Bradshaw and Finney and dozens of other scientists working up and down these hallways, part of the government’s Rocky Mountain Research Station….
“The thing we have to realize is that fires are inevitable. They’re impossible to completely exclude from the landscape,” Finney said.
“By trying to do that and doing it so successfully, what we’ve done is saved up the fires for the worst conditions. When you get rid of all the fires under moderate conditions, all you have left are the extreme ones.”
The other article is a column by George Wuerthner, which appear at The Wildlife News:
As large fires have spread across the West in recent decades, we hear increasing demands to reduce fuels—typically through logging. But logging won’t reduce the large fires we are experiencing because fuels do not drive large fires….
The ingredients found in all large blazes include low humidity, high temperatures, and drought. Assuming you have these factors, you can get an ignition if lightning strikes. But even an ignition won’t lead to large fires.
The final ingredient in all large blazes is wind.
Wind’s effect is not linear. In other words, increasing wind speed from 10 mph to 20 mph does not double fire spread, rather it leads to exponential fire growth and increases the burn intensity….
Most large fires have wind speeds of 30-50 mph or more. Wind makes fire fighting difficult since embers are blown miles ahead of the burning fire front. It is also the reason why wind makes fuel reduction projects ineffective.
Wind drives flames through and over fuel treatments. Even clearcuts with little or no fuel will not halt a wind driven fire. The wind driven fire just dances around and over any fuel breaks.
The biggest problem with fuel reductions is that one can’t predict where and when fires will occur. The likelihood of a wildfire will encounter a treated forest in the time scale when fuel reduction are effective is incredibly low.
The vast majority of acreage burning around the West are occurring in higher elevation forests like lodgepole pine and various fir species that naturally burn at infrequent intervals, often hundreds of years apart. As a consequence, a fuel treatment in such forests is a waste of time because the probability of a fire occurring at all in the time when fuel reductions are effectiveness is extremely low.
Even in drier forests like ponderosa pine that burn more frequently the chances that a fire will encounter a fuel treatment while it’s most effective is around 1-2%.
There is a role for fuel reduction projects. The best ones are targeted near communities and other areas of interest. The idea being one cannot predict where a fire may start, but one can predict what you don’t want to burn up in a fire. So focus fuels reductions adjacent to those places.
The most important fuel reduction projects should occur in the communities themselves. Removal of wood piles from adjacent to homes. Clearing pine needles from roofs. Getting rid of flammable building materials like cedar shake roofs.
Reducing the flammability of homes are the kinds of “fuel reductions” that work and should be encouraged. If these fuel reductions were implemented religiously, we wouldn’t have to worry about wildfires in the hinterlands, and we could permit these blazes to do the important ecological work they perform without continual interference from humans, yet feel secure in the knowledge that our communities were safe from wildfires.