Warning: session_start() [function.session-start]: open(/home/content/62/5841762/tmp/sess_dbj8q4mgpll860kujarbedaq41, O_RDWR) failed: No such file or directory (2) in /home/content/62/5841762/html/wp-content/plugins/si-contact-form/si-contact-form.php on line 1931
Playing the odds | Pamdemonium
Rss Feed
Tweeter button
Facebook button
Technorati button
Myspace button
Linkedin button
Webonews button
Delicious button
Digg button
Stumbleupon button
Newsvine button

Playing the odds

June 17, 2010

June is here, school is out, garden is growing and Shaun is venting, “It’s f*&k#ng hot” already. I am thinking about weather and hurricanes and probabilities.

The Atlantic hurricane season started June 1. Official forecasts suggest an “active” one, and today, more than 25 years of summer weather stories – written as an intern, dreaded as a reporter, assigned as an editor – are rumbling around in my head. At the Duluth News-Tribune, as a summer intern in 1982, I was tasked with a “weather project” about forecasting and trends. What stays with me, though, is Duluth’s “Weather Wizard,” a costumed character who forecast the weather each day by spinning a wheel on a local television newscast.

An intrepid young reporter, I compared the Wizard’s predictions with those of the National Weather Service to gauge their success. They tied.

This meant neither an inept Weather Service nor a powerful wizard. Weather forecasting is a science but not in the sense chemistry is a science. At its core, basic forecasting is more about probability, which is math. Atmospheric science just informs the odd-makers.

If the weather forecast predicts a 30 percent chance of rain for each of the next three days and I don’t water my garden, thinking, well, surely it will rain one of those days because that’s 90 percent, I’d be wrong. A 30 percent chance of rain means that three out of 10 times, under those exact same conditions, somewhere in the area the forecast covers, it should rain. But no one knows when that will be. Two weeks of daily “30 percent” forecasts and no rain doesn’t mean anyone was wrong. Thinking, “Gosh, here we are at Day 9 so it has to rain tomorrow,” in my case at least, means certain death for the garden.

This is less problematic at the high end, for a forecast of 90 or 100 percent chance of rain pretty much means rain. At the low end, 20 percent chance of rain means that 20 out of 100 times, or 200 out of 1,000 times, it should rain under similar conditions. Low odds, high crapshoot.

Redrum.

Gambling with my garden’s success is one matter; betting against the house with hurricane strike is another.

Atmospheric science has shaved many, many miles off what I like to think of as “the spread.” This is the potential strike zone, or area of likely landfall or, in the case of those of us afflicted with black humor, the cone of death. Each year, data collected by those brave souls in storm reconnaissance aircraft and other sources helps scientists improve forecasting. The pros shave off about a mile a year, and in 2008, Steve Letro, the meteorologist in charge of the National Weather Service in Jacksonville, Fla., told a conference of marina owners in Orlando that the error rate had been cut in half in 15 years.

Proximity is another factor, which is why the two-colored cone gets smaller as a major storm enters the Gulf and continues its march. But the inner, reddish cone is red for a reason. Red is bad. Red is run. Red is roulette, with even worse odds. If you are under a hurricane warning, the odds are one in three.

“Our biggest fear is that there will be a warning, you’ll evacuate, it will be a pain in the butt, nothing happens,” Letro told marina owners. “Then there’ll be a second warning, you’ll evacuate, and it will be a pain in the butt but nothing happens. Time three you don’t evacuate – and you get hit.”

And Mother Nature doesn’t keep score: Pass Christian, Miss., for example, doesn’t get to go to the end of the line after getting slammed. The once idyllic beach town, if in the forecasted strike zone, could get hit repeatedly in the same season.

I’ve had my share of vices. I’m just glad gambling isn’t one of them.

Check out that hurricane forecasting story I did for Madmariner.com.

Share

Comments on this entry are closed.

Previous post:

Next post:


Warning: Unknown: open(/home/content/62/5841762/tmp/sess_dbj8q4mgpll860kujarbedaq41, O_RDWR) failed: No such file or directory (2) in Unknown on line 0

Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct () in Unknown on line 0