The evolving (and inexact) science of escaping a fire

As fires brought down on the quarters through Los Angeles this week, residents and authorities faced a harrowing and almost impossible challenge: convince 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 fire evacuations into practice. The field is small but growing, reflecting recent studies suggesting that the frequency of extreme fires will more than double by 2023. The growth was driven by devastating fires in the western United States, Canada and Russia.

“Definitely the interest (in evacuation research) has increased because of the frequency of wildfires,” says Asad Ali, a doctoral student in engineering at North Dakota State University. that work focused on the field. “We’re seeing more publications, more articles.”

When the evacuations are wrong, they are really 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. Authority 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 reacts to what kinds of warnings? And when are people most likely to get out of harm’s way?

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

But hurricanes and wildfires are different in some obvious, and less obvious, ways. Hurricanes are usually larger, and affect entire regions, which can require multiple states and agencies to work together to help people travel longer distances. But hurricanes are also relatively predictable and slow, and tend to give authorities much more time to organize escapes and strategize for gradual evacuations so that everyone doesn’t hit the streets at once. Fires are less predictable, and require fast communications.

People’s decisions to go or stay are also affected by an inconvenient fact: Residents who stay put during hurricanes can’t do much to prevent disaster. But for those who stay in the fog of the fires to defend their houses with hoses or water, the gambit can sometimes work. “Psychologically, fire evacuation is very difficult,” says Asad.

Research so far suggests that reactions to wildfires, and whether people choose to stay, go, or even wait for a while, can be determined by a number of things: whether residents have been through fire warnings before , and if the authorities “forewarned real threats; how the emergency was communicated to them; and how the neighbors around them reacted.

One survey of about 500 California wildfire evacuees conducted 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 exact opposite. In general, lower income people were less likely to flee, possibly because of limited access to transportation or places to stay. These types of surveys can be used by the authorities to create models that tell them when to teach which people to evacuate.

One difficulty in fire evacuation research at the moment is that researchers don’t necessarily classify fire events in the “extreme weather” category, says Kendra K. Levine, the library’s director of the Institute of Transportation Studies at UC Berkeley. Santa Ana winds in Southern California, for example, are not unusual. They happen every year. But combine the winds with the historic drought of the region – and probably connected to climate change – and the fires start 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 that he has already had meetings on the use of data collected during this week’s disasters to use in future research. It is a faint silver lining, that the horror that Californians experienced this week could produce important results that help others avoid the worst in the future.