By the time the remnants of Hurricane Jeanne finally left Pennsylvania in late September, the storm had dumped more than ten inches of rain in some areas, sent several rivers spilling over their banks, snarled traffic and left homes across the area flooded.
She wasn’t alone. The storm was just the latest in a powerful series of hurricanes, including Ivan, that have battered the Caribbean and Eastern United States since hurricane season began in June.
But though he admits that 2004 has been busy, both in the frequency and strength of storms, Frederick Scatena says this onslaught of summer storms is really not much of an anomaly. "It’s not that unusual," says Scatena, who is chairman of Penn’s Department of Earth and Environmental Science. "There have been worse years." Also, he says, it was not entirely unexpected.
In fact, most experts, including the National Hurricane Center, had predicted just this kind of barrage way back in May. The Atlantic, it turns out, is in the midst of an extended "peak period" of hurricane activity, and the active hurricane season of 2004 is merely an extension of it, says Scatena, who has focused much of his research on the effects of hurricanes on the Caribbean.
Scatena says that since the mid-1990s the Atlantic has been churning out higher-than-normal numbers of storms, and 2004 merely continued the trend. The Atlantic also saw similar high levels of hurricane activity for extended periods in the 1930s, the late 19th century and the mid-18th century.
But while the current trend mirrors other such periods, Scatena also says there’s at least some chance the recent string of hurricanes may speak of a larger weather pattern. "If you look out there right now, it’s very chaotic," he says. "There’s much more going on than I’ve seen in years."
If the current string of high activity were to continue, he says, scientists may begin to wonder if other factors were fueling the storms. Because of the severity of the recent storms, he says, some scientists have wondered if global warming—and, as a result, warmer ocean temperatures—may be fueling an uptick in storm activity.
"If we continued to have peak seasons like these," he says, "then we would start being in periods never seen before."
Originally published on October 7, 2004