Future Tense for Mar. 3, 2007
By Steve Welker
I pulled some weeds and replanted some basil on the last Saturday in August. It was nothing very strenuous, but I gave up after less than an hour, soaked with sweat and feeling light-headed. The thermometer read 99 degrees. Yes, I know was August, but 99?
On Saturday, Sept. 1, one week later, the high was only 75. Thank heaven for the relief. I couldn't have taken much more of this summer.
Even if this cool spell doesn't last, I'm glad to see August gone. The National Climatic Data Center in Asheville says this past month in North Carolina was the hottest on record -- and the records go back 113 years. Raleigh-Durham, for one, equaled its all-time high, 105 degrees, on Aug. 21. Oldtimers hereabouts say they haven't seen a summer this hot since 1954.
Bad as the heat was here in the Tar Heel State, other parts of the U.S. had it as bad or worse. West Virginia, Tennessee, South Carolina, Georgia, Alabama, Florida and Utah also had the hottest Augusts in 113 years. South Carolina had 14 days in August when the high was 100 or above, breaking a record that dates to 1900. Cincinnati, Ohio, also broke a record with five 100-degree-plus days.
Nationwide, the average temperature was 75.4 degrees, which is 2.7 degrees about the 20th-Century mean, for the second-warmest August on record. More than 30 all-time-high records were tied or broken around the country.
Are these the signs of global warming?
It’s easy to reach that conclusion. National Oceanic and Atmospheric Administration climatologists say the whole summer, June through August, ranked as the sixth-hottest since 1895.
However, people who don’t believe theories of global warming can quote statistics, too. Texas and Oklahoma had a colder-than-normal summer.
Some of those skeptics believe every place on earth would be hotter if global warming exists and, because San Antonio didn’t get baked while Salt Lake City roasted, they conclude global warming is a myth. And if global warming doesn’t exist, they say, mankind cannot be causing it. Therefore, the skeptics conclude, humans cannot be causing “climate change.”
If the Olympics ran a competition for illogical leaps in logic, those global-warming critics would make Mike Powell or Bob Beamon look like puddlejumpers.
The fact is, the earth’s average surface temperature is rising. The clearest evidence comes from ocean temperatures charted worldwide for at least 125 years, but those records are backed up by other, less-precise indicators, such as tree rings, corals, ice cores and historical accounts. Also, judging by those indicators, the earth’s average temperature rose faster in the 20th century than at any time in the previous 1,000 years.
Not coincidentally, the atmosphere today holds a higher percentage of “greenhouse” gasses, such as carbon dioxide, that trap sunlight’s heat. This percentage has been rising since the 1750s, roughly the start of the Industrial Era, and accelerating since the 1940s.
Natural forces such as the sun’s variability and volcanic eruptions have always played a role in climate change, but Mother Earth has never seen anything like the impact of 6.5 billion human beings who burn forests, oil and coal at prodigious rates. Mankind is having an influence on global climate, but how much influence and what to do about it remain unanswered and, you should pardon the expression, hotly debated questions.
So, what happens if global warming continues?
In the past century, average sea level rose 4 to 8 inches. As temperatures rise, we can expect to see the oceans swelled by melting ice in the Arctic and Antarctica, on the Greenland ice shelf and from glaciers. By 2100, scientists predict, sea level could be 4 to 36 inches higher — the wide range suggests how much variation exists in current climate models — and some of North Carolina’s beaches will be much smaller if they’re not engulfed altogether.
With less ice on the ground to reflect the sun’s energy, major climate changes could occur in the following 200 years. Geologist John J.W. Rogers of UNC-Chapel Hill found evidence of a 50-foot rise in global sea level in the first two centuries after a glacial era ended about 15,000 years ago; it’s not inconceivable that it could happen again.
Now consider the lay of the land on North Carolina’s coastal plain. From New Bern, which is at sea level, the land’s elevation rises to only 15 feet at Washington, 35 at Goldsboro, 45 around Kinston and 55 at Greenville and Tarboro. A 50-foot increase in sea level would put about a third of the state under water.
Am I worried? Not living here in Mount Airy, 1,100 feet above sea level.
But I might advise my sons to invest in beachfront property for my great-grandchildren, perhaps on the east side of Wilson or Rocky Mount ... in the future.