CLIMATE WIRE | More than half a million Americans have come face-to-face with catastrophic wildfires between 2000 and 2019—partly because they lived in areas of high wildfire risk, but also because fires are getting bigger and encroaching on areas once considered lower risk. considered, according to research.
Those findingspublished in the magazine Nature Sustainability, reflect what Boise State University experts call “cumulative primary human exposure” to wildfires. It’s a sobering indicator of how wildfires are moving closer to populated areas, a condition that will worsen as the planet warms.
“This is a wildfire out of control,” said Mojtaba Sadegh, an assistant professor of civil engineering at Boise State and senior author of the study published this month. “In many cases, the population was already there, but the climate [conditions] were not ripe for frequent wildfires. Now they are.”
More than 8 in 10 people in the highest-risk areas — those within a “wildfire perimeter” — lived in Western states, particularly California, the researchers found. But more than 106,000, or 18 percent, of those at catastrophic risk were in states from the Great Plains to Florida.
“Our results highlight that deliberate mitigation and adaptation efforts to help societies cope with wildfires are increasingly needed,” the study said.
Researchers examined data from more than 15,000 wildfires in the lower 48 states between 2000 and 2019, then used population distribution data to estimate how many people were exposed to those fires. Findings show that exposure of the primary population to wildfires in the continental United States has increased by 125 percent in those 20 years.
Researchers warned there were “major statistical uncertainties” in the trend analysis due to the relatively short timeline of the study, but Sadegh said it’s clear that wildfires are increasing in intensity and frequency due to climate change.
Data modeling and analysis from independent groups such as the First Street Foundation have drawn similar conclusions about increasing wildfire risk.
While much attention has been paid to the encroachment of homes in fire-prone areas, the researchers found that an “increased size of wildfires was the cause of most of the observed trends.”
According to the Boise State study, only 24 percent of those most at risk for wildfires between 2000 and 2019 moved to a fire-prone region. Seventy-six percent already lived in what they believed to be fairly safe communities. “These people didn’t realize how dramatically wildfire dynamics would change over their lifetime,” Sadegh said in an interview.
In addition to the direct threats to life and property, health experts have warned of the indirect impacts of wildfires, including drinking water contamination, mud and debris flows, and smoke inhalation.
Tens of millions of Americans witnessed firsthand this summer how wildfire smoke affects human health. Smoke from Canadian wildfires has blanketed much of the United States in recent weeks, including the East Coast where such disasters are uncommon, at least for now.
“The eastern US has not seen the worst yet,” Sadegh said. “The projections show that future wildfires in the East are expected to increase [with climate change]and the wildfires there will be bigger and more intense.
Fires like those in Canada could become common in forests from Maine to Minnesota as conditions warm and drier, experts say. Northern Minnesota’s Superior National Forest, for example, has seen a marked increase in wildfires, including a 93,000-acre fire in 2011 in the pristine Boundary Waters Canoe Area Wilderness.
Sadegh said the findings have immediate implications for local, state and federal agencies responsible for maintaining firefighting infrastructure and workforces, as well as managing wildfire evacuations. Insurers are also becoming more aware of wildfire risk, particularly in places like California, resulting in rising premiums and even policy cancellations.
“This is something we have to live with; this is not going to go away, especially in the coming decades,” he said. “We need to think about how we can become more resilient to this.”
Reprinted from E&E News with permission from POLITICO, LLC. Copyright 2023. E&E News provides essential news for energy and environmental professionals.