Aug. 11, 1999 BUFFALO, N.Y. -- Fear not! The dog days oppressing much of the country with miserable heat, drought and brownouts are a normal part of the climatological pattern and do not portend disastrous climate changes, a University at Buffalo geographer says.
"No, it's not global warming," says Charles H.V. Ebert, SUNY Distinguished Teaching Professor in the Department of Geography in the UB College of Arts and Sciences. "That could be occurring as well, of course, but based on 100,000 years of geological evidence, we just seem to be going through a warm phase of our climatology.
"Drought occurs in almost every region on earth on a somewhat regular basis," Ebert points out. "Patterns of relatively wet, dry, hot or cold weather usually run in six-to-eight-year cycles. Drought is a result of one to three years of particularly dry, hot weather that climaxes in a relative disaster in some form -- crop failure, dry wells, serious wind erosion. Then its time is up and the dryness abates. Drought doesn't last forever.
"Rain comes and after a few years, it stabilizes the water table depleted by the drought. Then the rain abates and a drier period begins once more," he says.
Ebert notes that periods of intense or stalled weather conditions are likely to endanger or cause serious economic deprivation in the affected region. "But media attention, combined with our poor memories of past weather, tend to generate unjustified alarm for our climactic future," he says.
"People tend to take each unpleasant event thrown at us by Mother Nature worse than any they've ever experienced," he says. "That's why we're always worried about what a particular hot spell 'means.' It means about what the last one meant.
"We worry too much about this because our memories are short," he adds. "So every dramatic weather condition seems worse than it actually is. This may be the hottest July on record in many places, but there have been other very hot Julys -- does anyone remember the terrible heat wave of the 1980s?
"It was miserably hot in the East for some time and like today, people feared that it was a warning of future disaster. But who knows how many very hot summers have occurred over the last hundred thousand years?"
There are no written records of that period, of course, but Ebert again points to geological evidence that this summer is just part of a general warming pattern that will be followed by a cooling pattern; that this period of drought will be followed by a period of rain, then too much rain, and another weather "panic."
"We've had a spate of unusually hot weather that has built up slowly over the last few years and this year lasted longer than normal," Ebert admits. "But it's not a fluke. It's not unique. It has produced drought, but that was also to be expected based upon hundreds of years of recorded weather observations."
Ebert explains that the jet stream, which usually moves in an "s" pattern, generating cool, then warm weather, has been running parallel to the Canadian border lately, drawing warm air masses from the southern Gulf regions and giving the Northeast a long taste of the South's tropical, maritime weather.
"But the jet stream will spring back to life again and life will return to normal," he says. "It will cool off, we'll get rain, then more rain, then more, and people will again worry about the rainy years as they have about the hot years."
The unusually long heat wave is probably aggravated by the El Niño-La Niña cycle, Ebert says. The name El Niño, he points out, literally means "Christ Child," thus named by the Spaniards because the heavy rainfall it caused on the west coast of Peru and Ecuador every seven or eight years usually occurred at Christmas time.
El Niño conditions, produced by warmer-than-usual coastal water temperatures, are felt for one or two years, he says. After El Niño comes its aftermath, La Niña, when cool water rises to the surface of the coastal waters, stabilizing the air mass and initiating a dry period. This climaxes after a few years in relative drought.
"So we have a stalled Gulf Stream and the effects of La Niña operating right now," he explains. "It's no wonder it's hot and dry."
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