The evolving (and inexact) science of fleeing wildfires

like forest fires It swooped across the living Los Angeles This week, residents and authorities faced an agonizing and almost impossible challenge: convincing hundreds of thousands of people to leave their homes to escape danger, within hours or even minutes.

In doing so, officials put into effect years of research on evacuations in wildfires. The field is small but growing and reflecting Modern studies Which indicates that the frequency of severe fires has more than doubled since 2023. This growth was due to terrible fires in the western United States, Canada and Russia.

“Interest (in evacuation research) has certainly increased because of the frequency of wildfires,” says Asad Ali, an engineering doctoral student at North Dakota State University, whose work has focused on this area. “We’re seeing more posts, more articles.”

When evictions go bad, they really go bad. In the Pacific Palisades neighborhood of Los Angeles, panicked drivers stuck in traffic abandoned their cars in the middle of evacuation routes, leaving emergency crews unable to reach the fires. authorities Bulldozers used To push empty cars off the road.

To prevent this kind of chaos, researchers are trying to answer some basic but crucial questions: Who reacts to what kind of warnings? When are people most likely to stay out of harm’s way?

Many researchers’ ideas about evacuations come from other types of disasters, from studies of residents’ responses 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 may require many states and agencies to work together to help people travel longer distances. But hurricanes are relatively predictable and slow-moving, which tends to give authorities more time to organize escapes and strategize about phased evacuations, so everyone doesn’t hit the road at once. Wildfires are less predictable and require rapid communications.

People’s decisions to go or stay are also affected by an inconvenient truth: 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, this maneuver sometimes works. “Psychologically, evacuating from wildfires is very difficult,” Asad says.

The research so far suggests that reactions to bushfires, and whether people choose to stay, go or wait a while, can be determined by a range of things: whether residents have experienced bushfire warnings before, and whether These warnings may have been implemented or not. followed by actual threats; How to inform them of an emergency; How do the neighbors around them interact?

one reconnaissance Among about 500 California wildfire evacuees conducted in 2017 and 2018, they found that some older residents who had experienced a lot of previous wildfire incidents were less likely to evacuate — but others did just the opposite. In general, low-income people were less likely to flee, perhaps due to limited access to transportation or accommodation. Authorities can use this type of survey to create models that tell them when to direct people to evacuate.

One difficulty with current wildfire evacuation research is that researchers don’t necessarily classify wildfire events into the “extreme weather” category, says Kendra K. Levine, library director at the Institute for Transportation Studies at the University of California, Berkeley. For example, Santa Ana winds in Southern California are not unusual. It happens every year. But combine the winds with the region’s historic drought, likely linked to climate change, and the wildfires will look more like weather. “People are starting to come to terms” with this relationship, Levin says, which has led to more interest and scholarship among those who specialize in extreme weather.

Asad, the North Dakota researcher, says he has already held meetings about using data collected during this week’s disasters in future research. It is a faint silver lining that the horror Californians witnessed this week may lead to important findings that will help others avoid worse in the future.