The U.S. record $18 billion wildfire season of 2017 was triggered by the coincidence of three primary factors that came into play or persisted longer than anticipated, according to a new study led by a researcher at the University of Colorado.
Those “switches,” according to study leader Jennifer Balch, were ignition, aridity and fuel. The activation of all three resulted in 71,000 wildfires that torched 10 million acres, claimed 12,000 homes, required the evacuation of 200,000 people and killed 66.
That‘s nearly double the 5.4 million acres hit by wildfire in 2016.
“Last year, we saw a pile-on of extreme events across large portions of the western U.S: the wettest winter, the hottest summer and the driest fall — all helping to promote wildfires,” Balch, director of CU Boulder‘s Earth Lab at the Cooperative Institute for Research in Environmental Sciences, said in a statement.
Balch‘s paper, ” ,” was co-authored by researchers at CU‘s Institute of Arctic and Alpine Research, Columbia University and the University of Idaho. It was published last week in the journal Fire.
Already this season, the southwest is seeing signs of an active fire season, with in Colorado and New Mexico in recent days.
In an interview, Balch said that humans carry the blame for many fires, and also hold the key to mitigating fire danger.
“People start nearly 90 percent of our wildfires,” Balch said. “We provide the spark that sets those fires off. So, (we need to be) really aware of the fact that we carry fire with us wherever we go — whether that‘s campfires, or that can also be debris burning.”
We also do few favors for ourselves with the summer‘s central holiday, Balch said.
“The single day when we have the most (fires) is July Fourth. It‘s too bad our Independence Day didn‘t coincide with winter, because over 7,000 wildfires that started in the last two decades happened on July the 4th,” she said.
But while that is one day a year, another factor is with us every day of our present — and, for now, our future.
“We have known for over a decade now that wildfires‘ increasing number is linked to climate change,” she said. “It‘s 2 degrees Fahrenheit warmer in the western U.S. Snow melt is happening earlier in the season in the montane region. And the last thing is that the fire season is longer, by a couple of months. And, the lightning ignitions are happening only in the summer months. But people are providing ignitions across the whole year.”
Megan Cattau, an Earth Lab researcher and a co-author on the study, said in a news release, “We expect to see more fire seasons like we saw last year. Thus, it is becoming increasingly critical that we strengthen our wildfire prediction and warning systems, support suppression and recovery efforts, and develop sustained policies that help us coexist with fire.”
Balch emphasized the importance of prescribed burns in mitigating future fire dangers. Additionally, she said the philosophy behind floodplain mapping, which shapes public policy and local regulations in terms of where building can take place — and at what cost — should be applied to wildfire management.
“We have floodplain maps that help us by incentivizing where we build based on flood dangers, but we don‘t have firescape mapping, indicating where future wildfires might happen,” she said.
“It‘s being talked about in the context of California. California is definitely ahead of us in terms of how to incentivize building.”
While the recent statistics — as well as the current societal and climatalogical landscape — can be discouraging, Balch has some degree of optimism.
“The one thing that‘s really important with wildfire is that it responds to a changing climate. And to ignore the link between wildfires and changing climate is to put lives and property at risk. And wildfire is one of the real in-your-face ways that we‘re going to see the results of climate change,” she said.
However, Balch added, “I am hopeful. There‘s a lot we can do. It‘s really a low-hanging fruit, to improve the way we‘re building.”