The evolving (and imprecise) science of wildfire escape

like forest fires headed for the quarters opposite Los Angeles this week, residents and authorities were faced with a harrowing 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 evacuations into practice. The field is small, but it is growing, reflecting recent studies suggesting that the frequency of extreme fires has doubled since 2023. this way. The increase was driven by devastating wildfires in the western United States, Canada and Russia.

“Certainly the interest (in evacuation research) has increased because of the frequency of wildfire burns,” said Asad Ali, a doctoral student in engineering at North Dakota State University whose work focuses on the area. “We’re seeing more posts, more articles.”

When evacuations go wrong, they really go wrong. In the Pacific Palisades neighborhood of Los Angeles, 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 the 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 kind of warnings? And when are people most likely to get out of harm’s way?

Many of the researchers’ ideas about evacuations come from other types of disasters—from studies of residents’ responses to floods, or nuclear disasters, or volcanic eruptions, and especially hurricanes.

But hurricanes and wildfires differ in some obvious and less obvious ways. Hurricanes tend to be larger and affect entire regions, which can require many countries and agencies to work together to help people travel longer distances. But hurricanes are also relatively predictable and slow-moving, and usually give authorities much more time to organize escapes and strategize phased evacuations so that everyone doesn’t hit the road at once. Wildfires are less predictable and require rapid communication.

People’s decisions to go or stay are also influenced by an inconvenient fact: Residents who stay during hurricanes can’t do much to prevent disaster. But for those who stay in the haze of wildfires to protect their homes with hoses or water, the gambit can sometimes work. “Psychologically, wildfire evacuation is very difficult,” says Assad.

Research so far suggests that responses to wildfires, and whether people choose to stay, leave or even just wait for a while, can be determined by a number of things: whether residents have received wildfire warnings before, and whether authorities’ warnings, antecedent actual threats; how the emergency is communicated to them; and how the neighbors around them react.

one study of about 500 California wildfire evacuees in 2017. and 2018 found that some longtime residents who had experienced many previous wildfire incidents were less likely to evacuate, but others did the opposite. In general, people with lower incomes are less likely to flee, possibly because of limited access to transportation or accommodations. These types of studies 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 as “extreme weather,” says Kendra K. Levin, director of the library at the Institute for Transportation Studies at the University of California, Berkeley. Santa Ana winds in Southern California, for example, are not uncommon. They happen every year. But combine the winds with the region’s historic and possibly climate change-related dryness, and wildfires start to look more like the weather. “People are coming to terms” with the connection, Levin says, which has led to more interest and scholarship among those who specialize in extreme weather.

Assad, the North Dakota researcher, says he has already had meetings about using data collected during this week’s disasters for use in future research. It’s a faint silver lining that the horror Californians experienced this week may lead to important discoveries that will help others avoid the worst in the future.