Wednesday, August 17, 2011


           You will no doubt be pleased to hear that the National Weather Service (NWS) has somewhat gleefully raised its ante in the annual “How many named storms/hurricanes/major hurricanes will develop in 2011?” sweepstakes. This yearly competition annoys me. Don’t know what the prize is. Bragging rights, perhaps? Proving to Bill Gray and the gang at Colorado State that people living in the Rockies know bugger-all about Atlantic cyclones?

Dr. Bill Gray and heir-apparent
Philip J. Klotzbach
            Safe in their mountain stronghold, the hurricane oracles at CSU have been uncharacteristically reticent about upgrading their own prognostications. The bombastic Dr. Gray and his lads have toned down their hubris levels considerably since the embarrassing failure to prophesy the many devastating storms of 2005, followed by years of apocalyptic predictions that served mainly to sink coastal dwellers into a morass of apathy via crisis overload.

The famous Cape Verdean
           Be that as it may, the gavel-to-gavel coverage has begun of every butterfly wing-flutter on the Cape Verde Islands as we roll into the most active part of hurricane season.

The whole animus of weather prediction is fatally flawed, of course. Why? Because anyone who pays the slightest attention to what’s going on outside—you know, the weather—knows that what’s coming next is anybody’s guess. Modern meteorologists dislike this indisputable phenomenon. “But look at our computer models!” they wail, and point at monitors in the climate-controlled, windowless rooms they inhabit. (And what’s wrong with that picture?) They could achieve the same rate of forecasting success they currently enjoy by mumbling incantations over chicken entrails, rolling dice, or playing Rock, Paper, Scissors.

1989's Hurricane Hugo,
from space
(photo courtesy of NASA)
            But I digress. The 2011 Atlantic hurricane season has been satisfyingly active so far in one sense: we’ve racked up seven named storms. The boys in Fort Collins and Miami are salivating. Still, no hurricanes of any category under our belts, and no on-shore death and destruction, just the odd rainy day in the Caribbean and on Bermuda.  That said, it seems to me the entire divination exercise is ancillary. By virtue of being ocean-dependent for development, tropical cyclones always give lots of warning before impacting land: 2005’s Katrina was in the news for weeks before she roared ashore as a Category 4 storm at New Orleans. The devastation that followed was a political failure, not a meteorological one. It’s not comparable in any sense to the tornadoes that flattened Joplin, Missouri this spring. The people there didn’t have days and days to prepare, like the inhabitants of New Orleans did. (Of course, New Orleans’ population is a brick short of a load anyway, building their city below sea-level. How stupid is that? The only places that kind of thinking works is in the Grand Canyon and Death Valley.)

One of my worst nightmares
             Tornadoes, earthquakes, tsunamis, blizzards and floods all afford appreciably less in the way of lead time than hurricanes. In particular, tornadoes top the list of potential severe weather events that scare me silly. They’re freaky and capricious, flattening structures on one side of a street while leaving the other side untouched. They blow up out of nowhere and just as suddenly disappear, only to wreak havoc somewhere else. Or not. In terms of opportunities to prepare, hurricanes are a comparative stroll on the beach. So what’s the big deal with guessing how many will form between June 1 and November 30? What a waste of resources.

I’m one of those people who talk back to the television. One of my pet peeves is the comparison of today’s temperatures or rainfall with the “normal” for that day. “It’s average, you dolt,” I growl, “not ‘normal.’”

Turns out, while semantically correct, I’m technically wrong about that. (And, although I haven’t apologized, I have stopped correcting the TV screen every evening.) Once a decade, the National Oceanic and Atmospheric Administration (NOAA) collates daily temperatures and rainfall for the most recent 30 years, which it then averages before publishing the results as the “normal” for that decade. Words matter to me: not so much to the NWS. I continue to say “normal” in reference to temperature and rainfall with a slight sneer, which translates to using quotation marks in print.

We are currently undergoing the decadal re-evaluation of climate “normals.” If you regularly check the NWS almanac website, you’ll have noticed the “normal” values have been missing since the first of August. NOAA processes millions of pieces of weather information collected daily from thousands of sites nationwide through their super-computers to churn out the new numbers.  Here are some graphics depicting the changes from “normal” for 1971-2000 to the new “normals” for 1981 to 2010.

(Locals, rejoice! Next year I begin my own number-crunching project to reveal the ten-year “normals” for Oak Island! Watch this space!)

The ’70s were an unusually cool decade, statistically speaking. (I thought myself pretty cool in those days as well.) Turns out the years 2001 to 2010 were the warmest on record—but keep in mind that record-keeping only began in 1874, a mere fraction of the briefest blink in geologic time. Calculating the new “normals” by tossing out the ’70s and adding the aughts resulted, unsurprisingly, in warmer “normal” temperatures. “For the United States as a whole,” says Jennifer Freeman in a ClimateWatch magazine article, “it was not daytime highs… but overnight lows… that rose the most compared with the 1970s.”  This statement is borne out by my anecdotal local observations since 2002.

Chicken Little and friend react
to the latest climate "normals"
            Do the new “normals” offer irrefutable evidence of global warming? Hard to say, really. A mere 137 years of systematic record-keeping don’t supply enough data to draw reasonable conclusions. I’m old enough to remember the doomsters moaning about an imminent Ice Age during those “unusually” chilly summers of 40 years ago. Is the climate changing? Of course it is. It always does. Just the fact that our best weather minds seem fixated on a range of “normal” anything on this tiny volatile rock spinning in the inconceivable vortex of space and time sounds more like Chicken Little’s “The sky is falling!” than any preordained cosmic truth.

What the new “normals” do offer is a guideline for day-to-day choices in our gardens. It’s why I participate in phenologic observation projects like the Great Sunflower Project and National Phenology Network’s Nature’s Notebook program. Change is eternal. We have the option either to embrace it or waste our lives mourning what might have been (whether it might actually ever “have been” or not).

On a practical note, I recommend avoiding plants labeled AHS cold-hardiness Zone 8 and lower for long-term survival in southeastern North Carolina. They might require chilling periods greater than we experience.

A funny story about weather instruments, and then I’m done for today. One Christmas, Tim got me a very nice digital weather station from a reputable instruments company. We set it up, wiring the hygrometer, rain sensor and anemometer to the base unit. Despite my hard-core technophobia, I enjoyed the novelty of taking weather observations from inside the house. For a while. Six months later, lightning struck four houses north of us. By the time the reaction hit our house, it still had enough oomph not only  to fuse all our ground-fault interrupter circuits but to blow out the weather receiver as well. Tim called the reputable instruments company and told them what happened. Their service rep politely informed him that their warranties do not apply to instruments out in the weather. “But it’s a weather instrument,” Tim explained. “I’m sorry, sir,” she said, and that was that.

My off-the-grid
weather data-collection
            Now I use a mechanical barometer and a Radio Shack el-cheapo minimum/maximum thermometer. When it starts acting funky, we just go buy a new one. Wind and Weather catalog supplied a professional-grade hundredth-inch rain gauge, which we hung on the outdoor shower. Our front door conveniently faces due west, the bedroom window east; the ocean is 800 yards to the south, the Intracoastal Waterway 800 yards to the north. With a working knowledge of the Beaufort scale, I estimate wind direction and speed by looking at the trees and the clouds. Low tech, sure, but it doesn’t belly-up in thunderstorms.

            Thanks for dropping by. And keep your weather eye out.


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