As wildfires ripped through neighborhoods in Los Angeles this week, residents and authorities faced a crushing and nearly impossible challenge: convincing hundreds of thousands of people to leave their homes to escape danger, in a matter of hours or even minutes.
In doing so, officials put years of research into wildfire evacuation into practice. The field is small but growing, reflecting recent studies that suggest the frequency of extreme fires will more than double since 2023. The growth has been led by terrible fires in the western United States, Canada and Russia.
“Definitely the interest [in evacuation research] has increased due to the frequency of wildfire burns,” says Asad Ali, an engineering doctoral student at North Dakota State University whose work has focused on the area. “We’re seeing more publications, more articles.”
When evacuations go wrong, they really go wrong. In LA’s Pacific Palisades neighborhood, panicked drivers stuck in traffic abandoned their vehicles in the middle of evacuation routes, leaving emergency crews unable to reach the fires. Authorities used bulldozers to push empty cars off the road.
To prevent this kind of chaos, researchers are trying to answer some basic but critical questions: Who responds to what kinds of warnings? And when are people most likely to get out of the way?
Many of the researchers’ ideas about evacuation come from other kinds of disasters – from studies of residents’ reactions to floods, nuclear disasters or volcanic eruptions, and especially hurricanes.
But hurricanes and wildfires differ in some obvious and less obvious ways. Hurricanes are usually larger and affect entire regions, which can require many states and agencies to work together to help people travel longer distances. But hurricanes are also relatively predictable and slow-moving, and they tend to give authorities much more time to organize escapes and to plan evacuations in stages so that everyone doesn’t hit the road at once. Wildfires are less predictable and require quick communication.
People’s decisions to leave or stay are also affected by an inconvenient fact: Residents who stay during hurricanes can do little to prevent disaster. But for those who stay in the middle of wildfires to defend their homes with hoses or water, the gambit sometimes works. “Psychologically, wildfire evacuation is very difficult,” says Asad.
The research so far suggests that reactions to wildfires, and whether people choose to stay, go or just wait a while, can be determined by a lot of things: whether residents have experienced wildfire warnings before, and whether those warnings were followed by actual threats; how the emergency is communicated to them; and how the neighbors around them react.
A study of about 500 California wildfire evacuees conducted in 2017 and 2018 found that some long-time residents who have experienced many previous wildfire events are less likely to evacuate — but others did the exact opposite. In general, people with lower incomes were less likely to flee, possibly because of limited access to transportation or places to live. This kind of research can be used by authorities to create models that tell them when to instruct which people to evacuate.
One difficulty with wildfire evacuation research right now is that researchers don’t necessarily classify wildfires in the “extreme weather” category, said Kendra K. Levine, library director at the Institute of Transportation Studies at UC Berkeley. Southern California’s Santa Ana winds, for example, are not unusual. They happen every year. But combine the wind with the region’s historic — and likely climate change-related — dryness, and the wildfires start to look more like the weather. “People are starting to come to terms” with the relationship, Levine says, which has led to more interest and scholarship among those who specialize in extreme weather.
Asad, the North Dakota researcher, says he’s already had meetings about using data collected during this week’s disasters in future research. It is a faint silver lining that the horror Californians experienced this week may produce important results that will help others avoid the worst in the future.