The Spring edition of Fire Chief magazine is devoted to the
history, current trends and future of the wildland/urban interface fire threat. An article on pages 14 through 17 by Sarah Calams is titled, “Learn from past wildfires to fight future blazes: Understanding the scope and costs of historic and recent wildfires is necessary to plan for future fire suppression efforts”.
Below is an excerpt from the article, reprinted with their permission:
In 1845, 1.5 million acres burned during the Great Fire in Oregon. In 1871, the worst recorded forest fire in North American history occurred in Wisconsin. The Peshtigo Fire burned over 1.2 million acres and killed an estimated 2,200 people. Coincidentally, the Great Chicago Fire occurred on the same day.
Fast-forward to the present and consider the number of major wildfires in the past decade. One of the largest fires in Oregon’s history occurred in 2012, and 19 firefighters were killed during the Yarnell Hill Fire in 2013. The Rim Fire, one of the largest fires in California’s history, also happened in 2013.
While the number of acres destroyed has increased over the decades, the number of fires has decreased. Nonetheless, U.S. firefighting suppression costs are expected to rise.
In 1990, those suppression costs were almost $400 million, while in 2000 costs were a little under $1.5 billion. Likewise, in 2016 costs reached almost $2 billion, according to the National Interagency Fire Center.
More than 10 million acres were scorched in 2015, while a little over 4 million acres were destroyed in 1990. As more acres burn and more human building reaches deeper into forested areas, the WUI threat rises.
Bill Gabbert, who worked as a wildland firefighter in Southern California for 20 years and currently owns and manages WildfireToday.com, said one reason for the growth of wildfires is due to the more frequent occurrences of extreme weather.
According to Gabbert, extreme weather conditions, including drought and higher temperatures, can result in lower moisture content in vegetation. “Firefighters call this ‘fuel moisture,’” he said. “The less moisture there is in the live and dead fuel, the easier it is for fires to ignite and spread.”
That ignition, according to the National Park Service, is almost always caused by humans. The agency says that humans have a hand in starting 90 percent of wildland fires in the United States.
Human-caused fires can result from campfires left unattended, negligently discarded cigarettes and acts of arson, the NPS reports.
As a result, Gabbert said he’s skeptical of just naming weather as the main responsible factor in the number of fires and acres burned over the years.
“It is very difficult to say that one factor caused fire occurrence to change,” he said.
Other factors to consider, Gabbert said, include the capacity to suppress wildfires, the fact that more people are living and reconstructing in the wildland/urban interface, changes in vegetation and how timber is managed, fuel treatments, and changes in wildfire management policy…”