Dr. Bill Gray and heir-apparent Philip J. Klotzbach |
The famous Cape Verdean butterflies |
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) |
One of my worst nightmares |
*****
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.
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.
Chicken Little and friend react to the latest climate "normals" |
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 instrumentation |
Thanks for dropping by. And keep your weather eye out.
Kathy
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