Why some people never evacuate during a hurricane, according to a psychologist

The forecasts for Hurricane Irma are dire.

Much of Florida is now under a hurricane warning. Dangerous, threatening conditions are imminent. Tampa, a city particularly vulnerable to flooding, may see a direct hit. But Irma, with its hurricane-force winds extending 80 miles out from its center "will bring life-threatening wind impacts to much of Florida regardless of the exact track of the center, the National Hurricane Center reports. The greatest danger in a hurricane, however, is usually flooding from storm surge. And the hurricane center predicts 10 to 15 feet of surge is possible along the Southwest Florida coast. And severe impacts in Georgia and Carolina are also a possibility.

This storm poses a threat to life and property, and so far, evacuations in Florida — in cities as far away as Miami and Tampa were ordered. "You need to leave — not tonight, not in an hour, right now," Florida Gov. Rick Scott said on Saturday. "This is the most catastrophic storm the state has ever seen."

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But there's no amount of messaging that will get 100 percent of a population to evacuate. "There's a certain population that's never going to leave," Cara Cuite, a Rutgers psychologist who heads an NOAA-sponsored project on best practices in storm communication, told us last year.

And already a few Floridians in the path of the hurricane who've been told to evacuate are refusing to leave their homes. Why? The reasons are a bit complicated — and they reveal a lot about how risk is perceived and communicated. Let's break them down.

@JinATX: A surprising number of folks tell us they're planning to hunker down in Aransas Pass, under a mandatory evacuation. #Hurricaneharvey

There are myriad environmental or personal reasons why people don't evacuate.

• There are people who don't leave due to disabilities — they simply can't get out of their homes and don't have anyone to help them.
• Then there could be cases of people who don't hear the warning. But in an age when warnings can be blasted out via radio, TV, and smartphones, and through old-fashioned door-to-door notifications, this is becoming less likely.
• And then there are people who can't stand to leave their pets behind. A 2011 poll sponsored by the ASPCA found that around 30 percent of dog and cat owners who live in the South (where hurricanes are more common) wouldn't know what to do with their pets during an evacuation. In 2006, Congress passed the PETS Act, which mandates that disaster preparedness plans take into account companion animals, though adoption of the law has been scattershot, a 2013 report found.
• Even people with greater means sometimes refuse to evacuate. Some won't leave in fear of their home being damaged or looted, Cuite said. Or they'll remember weathering a previous storm and feel confident in their ability to survive the current one.
• And some research suggests that if public officials make evacuation orders mandatory, people are somewhat more likely to heed the orders and flee. One study in the Journal of Transportation Engineeringconcluded that mandatory evacuation order increases the likelihood of evacuating by 6 percent (using data from Hurricane Ivanin 2004). A voluntary order increases the likelihood by 4 percent.

Corpus Christi Mayor Joe McComb — whose city is directly in the likely path of the storm — only issued a voluntary evacuation, saying Thursday, "I think people are smart enough to make their evacuation decisions, and they don't need the government telling them what to do." Hopefully, people will evacuate anyway.

During Hurricane Katrina, people who refused evacuation orders were cast in a negative light: as too lazy, too uniformed, or too self-centered to make the decision to leave. The decision to stay was framed as a negative choice. But those who made the decision to stay saw it completely differently.

That was the conclusion of a 2009 paper in Psychological Science. Agroup of researchers at Stanford and Princeton surveyed Hurricane Katrina survivors and people who were not in the storm's path, asking them about their perception of the people who refused evacuation orders.

"There's this mismatch between the way that the event was seen from the outside and the way that the people themselves actually experienced it," Nicole Stephens, who led the study, said in a press release when the study was published.

The people who refused during Katrina were less financially secure than those who left, the study mentions, so they couldn't leave as easily. But the study concludes that doesn't mean they weren't proactive.

Their proactive measures included "connecting to others, being strong, and maintaining faith in God," the study found. "Given the limited material resources available in working-class Black contexts, stayers more often than leavers emphasized the importance of connection to and caring for others."

For these people, the thought of leaving was the selfish choice. We ought to remember that if we hear reports of significant numbers of people waiting out Irma at home. And through it all, people generally feel like they have agency. They're making their own decisions.

In the course of her research, Cuite has been talking to first responders, asking them what works to get people to evacuate. Some approaches used are drastic, like writing Social Security numbers on people's arms in permanent marker (so that search and rescue can identify their bodies), having people fill out "next of kin" contact form, or telling residents rescues will not be available in their neighborhood.

"It's trying to make people scared," Cuite says. "But the issue with scaring people is that you want to make sure they have the information they need to evacuate: Here's how you evacuate, here are the best roads to take, here's where the shelters are," and so on.

(It's important to note that it's really difficult to do research on storm messaging. You can give people surveys about how they might respond, but it's much harder to see how they actually do respond in an actual emergency.)

Overall, she stressed, evacuation warnings are really, really tough to get right. There are so many ways they can backfire.

For instance, take the "shadow evacuation" effect: That's when people on the "safe" side of an evacuation border decide to leave too. This can clog up roads and other emergency response resources. And Cuite says the "crying wolf" effect is real. If emergency managers make catastrophic predictions with too much confidence, and then those forecasts change, people might not listen as carefully in the future.

The New York Times outlined some strategies authorities are trying to communicate the urgency of a hurricane threat and what to do in one. For instance, authorities shouldn't compare new storms to old storms because "making comparisons can give residents a false sense of security." And it may seem obvious, but it is important for warnings to be as specific as possible, setting a deadline for people to leave.