by Judith Curry

As Major Hurricane Irene prepares to sideswipe the entire east coast of the U.S. north of North Carolina, what makes people discount or respond to to information on an impending disaster?

Andy Revkin at Dotearth has a post entitled “As Irene approaches, so does challenge of heeding warnings about rare threats.”    The post features an essay by David Ropeik, a consultant in risk communication and author of “How Risky Is It, Really?.”

A serious earthquake shakes the Mid Atlantic and New England states, and the reaction is as much excitement as fear. Now a serious hurricane bears down on tens of millions of Americans. How will they respond? The psychology of risk perception suggests that in many cases their reactions won’t match the realities of the danger, and as a result, some of their choices and behaviors might not maximize their safety.

Hurricanes are thankfully rare in the Northeast. The more powerful, more dangerous ones are rarer still. Few of those threatened by Irene have lost homes or property, or loved ones, or even just lost electrical power, or water, or phone/cable/Internet connections for days or weeks, the way people have in the Carolinas, Florida, the Gulf Coast states. Hurricanes in the Northeast are like earthquakes in a way — rare oddities to Twitter and text about as much as to fear.

What that means in terms of the way we perceive risk is that, even now, this threat remains abstract. It’s data about wind and rainfall and storm track. It’s information -– and as alarming as that information may be, risk perception is not just about the facts but how those facts feel, and an abstract risk usually doesn’t trigger as much concern as something we’ve actually been threatened by, or suffered from, in the past.

So while warnings will cause high alarm in some, and some people may be stocking up on bottled water and batteries, many will fail to take adequate precautions, and that leaves them at greater risk.

For the same reason, should evacuations be recommended, many might not follow that advice. And should evacuations be mandatory, some will resist, not only because they don’t take the risk seriously enough, but also because they fear that their property might be looted. We always weigh risks against benefits. Anyone who stays to protect property is making a risk-versus-benefit choice that says the risk of a hurricane – which in a mandatory evacuation area includes the risk of dying – doesn’t feel as big as the benefit of protecting your replaceable physical belongings. OOOPS!

For those of us who have lived through hurricanes in the Mid Atlantic states and Northeast, another psychological factor can diminish concern – the, “I’ve lived through this before” effect, a false sense of familiarity. Risk perception research has found that when we grow familiar with a risk…when we have experienced the danger but not suffered…we start to take it less seriously. The problem of course is that not every hurricane is the same. The hurricanes to make landfall in New England in some of our lifetimes -– Agnes in ’72, Gloria in ’85, Bob in ’91 — were weaker or smaller thanThe Great New England Hurricane of 1938 that hit as a Category 3 storm, causing serious damage from the Mid Atlantic states up to southern Quebec, and killing between 682 and 800 people, damaging or destroying 57,000 homes, and causing damage in today’s dollars of $4.7 billion. But few of us around now lived through that.

(Some in New Orleans made this “I’ve lived through it before, I can do it again” judgment as Katrina bore down, having survived even the Category 5 storm Camille in 1965. Not to be melodramatic about it, but some of the New Orleanians who perceived the risk of Katrina that way are now dead.)

Then there’s the seductively reassuring, and in the case of big storms false, sense of control. Some may not take adequate precautions, or evacuate, because they think that if things get really bad, then they can get out, or sandbag their house against flooding, etc. This is dangerous hubris, but a common phenomenon of risk perception. The more control you think you have the less afraid you are. Documentaries about the ’38 Great New England Hurricane tell a number of these stories, and some of them are abut people who thought they had more control than they did, and perished.

The ultimate example of all of this will be the people who go out in the storm, even down to the waves and surging sea at the coast, to see what it’s like. I was a TV reporter and covered big storms in New England for two decades. It can be exciting. It is also, I promise you, unequivocally scarier than you would think. But then, risk perception isn’t just a matter of rational thinking. It’s about our gut feelings too.

The real world bears out what the risk perception research has learned. Look at how Floridians behave when hurricanes loom. Their firsthand and relatively frequent experience with the fierce destructive danger of these storms makes the risk more visceral, and they take it seriously. They make their personal preparations, protect property, leave when it’s recommended. They know where the evacuation routes are. Do most of us in the Mid Atlantic and Northeast? Probably not.

After Katrina hit New Orleans, the evacuation from Houston several days later in advance of Hurricane Rita was unprecedented, far greater than expected by emergency planners. Roads jammed for hours as tens of thousands fled, far more than would probably have left except the terrible power of hurricanes was tragically viscerally real because of what had happened a few hundred miles to the east just days before. In fact, Houston was full of refugees from Katrina, sharing their firsthand stories, and making the threat that much more compelling.

There is a lot of alarmist coverage of Hurricane Irene, but the storm may change its course, weaken over the cooler ocean waters off the middle of the east coast, and come ashore, if at all, as a weaker storm — still dangerous, but short of Stormageddon. Regardless of the way the actual storm plays out, the way we perceive this risk offers a cautionary tale. It’s just one example of how our perception of risk, an affective/instinctive mix of facts and feelings, cognition and intuition, reason and gut reaction, can pose risks all by itself.

JC comment:  Hurricane Irene has been an exceptionally predictable storm, we saw this coming weeks in advance.  Given the northward track parallel to the coast, much of the coast won’t be exposed to the deadly right front quadrant of the storm, which is where the heaviest rains and tornadoes are.  Also, given the counterclockwise circulation of the storm, storm surge should not be very high at those locations parallel and to the west of the storm direction of motion.  Cape Cod and Maine could see a more direct strike with significant storm surge and exposure to the damaging part of the storm.  But given the high density of population, wealth and property in this region, it could be a collosally damaging storm. Pielke Jr has a post on potential damage estimates.

And finally, I’m sure you knew it had to be coming:

Irene’s got a middle name, and it’s Global Warming

The quote is from Bill McKibben, cited in a post at Collide-a-Scape.  Apparently Kevin Trenberth’s reversal of the null hypothesis has taken hold in certain segments.