I’m not sure what happened, but somehow I got to be very sensitive to gross exaggeration and hyperbole along the way, especially when it comes to the use of history and statistics. Or at least I hope that it is really just me. Today’s example comes from Ray Nagin, Mayor of New Orleans, as brought to us by the Chronicle:
“You need to be scared and you need to be concerned and you need to get your butts moving out of New Orleans right now — this is the storm of the century.”
Depending upon whether you are a traditionalist or not, the current century is either in its seventh or eighth year, and already we have had many strong hurricanes, Gustav merely being the latest. While I commend Mayor Nagin’s desire to convince people to evacuate, over-sensationalizing the danger isn’t necessary, but it just seems irresistible. For example, this should be warning enough for people who survived Katrina:
“For everyone out there that thinks they can ride this storm out, I have news for you, that will be one of the biggest mistakes you can make in your life.”
Mortal and imminent peril? You’ve got my attention. Mandatory evacuation? I’m packing. Free bus ride if I can’t afford it? I’m out the door. Person who is telling me all of this is blowing stuff out of proportion? Well, maybe I’ll stay. Exaggeration tends to blunt the message as it starts calling into question the messenger’s credibility, and this isn’t something where you need to overplay the danger. I don’t need it to be the biggest great white shark in the ocean for it to be a Bad Idea for me to go swimming right now.
Pop Quiz: Which was the “crime of the century” in the 20th century?
a) Lindbergh kidnapping b) Rosenberg conspiracy c) Tate/La Bianca murders d) Nicole Brown Simpson’s murder
That being said, these are some the less damaging examples. More pernicious, perhaps, is when a bureaucrat’s best intentions cause collateral damage. I have a love-hate relationship with government bureaucracy. On the one hand, as a consumer, I hate having to wait in lines and wish that things would be faster and more efficient so I could go about my day. On the other hand, I respect the wisdom of Frank Herbert’s Bureau of Sabotage. Bureaucrats’ most sublime purpose in life ought to be to blunt the ill-thought out, ill-defined, ill-targeted and ill-funded policies that come from the under-informed and over-zealous politicians who happen to make the mistake of getting enough other under-informed and over-zealous politicians to agree with him or her to make their will law.
Where was I? Oh, yeah, flood plain maps. After all, it is hurricane season. In case folks haven’t looked at the flood contours near where they live, I highly recommend wandering over to FEMA’s website, and taking a look at the relevant flood map for your area. The Harris County Watershed Maps from the Tropical Storm Allison Recovery Project (TSARP) are also fun.
What’s interesting about these maps is not so much what they are, but it is what they are not. What they purport to be is a topographical contour map that shows flood probabilities. The biggest problem is that they use a short-hand notation for probability (e.g., “100 year” and “500 year” flood plain) that is incredibly misleading. If I remember my Texas History from back in finger-painting school, Texas was inhabited by people like the Comanche, Apache and Karankawa tribes who, I believe, deleted all of their climatological databases from their hard drives when the neighborhood got so bad from “those people” moving in that they decided to move out. Or something like that.
Since climatology is, inherently, highly dependent upon empiricism and inductive methods, it seems odd to me that we would express probabilities (0.2% chance in a given year) in ways that were overly-reassuring given the nascent nature of the underlying science. In the back-half of the 1990s, I seem to recall half-a-dozen or so “100 year floods”. Not to open up a discussion on a Gambler’s Fallacy, or anything, but it seems like either God hates us or the models are bad.
This is before we understand that, necessarily, these models are done ex post facto, and don’t necessarily account for the continual re-shaping of the watersheds and the climate. The more of the Katy Prairie that gets paved over, the more downtown Houston is going to flood, no matter what the maps say. The more it rains in a given year, the more likely you are to get flooding (both from an independent and dependent probability perspective – ground saturates, after all). Analytical conveniences are convenient for the lay person who will struggle to grasp the basic concept, but they also often hide important information.
The big finish: we’re in the 500-year flood plain, but we’ve lost a car in the past to sheet flooding, so we carry flood insurance. I’m not saying you should, too, but just remember, if the water looks like it may be troubling, pay attention to it. And that’s not hyperbole, it’s just common sense, no matter how improbable you think it might be.