Severe Drought Cuts Costly Paths Across U.S.

August 16, 2002
By ANTHONY R. WOOD, Philadelphia Inquirer

A visceral drought has spread like wildfire across the Plains, the West and, of course, the East in recent weeks and could end up being the nation's worst in a half-century.

The government's U.S. Drought Monitor reported yesterday that 56 percent of the nation (excluding Alaska and Hawaii) was in at least moderate drought, with 40 percent in severe drought. Those numbers are about four times higher than normal, and would rank this drought among the most severe on record.

In some places, it already is.

The Southwest experienced its driest January-to-July in recorded history. In the West, that period was the fourth driest. That likely has played a role in the fast spread of West Nile virus: The mosquitoes that carry it and the people they bite are drawn closer together around what little water is left.

In other dry news, the wildfires are still burning.

"This drought isn't unprecedented - yet," said Mark Svoboda, a climatologist with the National Drought Mitigation Center in Lincoln, Neb. "And that's a big yet."

Neither the short-term nor long-term forecast holds out much hope for widespread drought-quenching rain in much of the country.

"It's certainly safe to say that we're in the billions of dollars in damages in terms of crop damages," said Doug LeComte, a drought specialist with the government's Climate Prediction Center in Silver Spring, Md. Crop losses in just two hard-hit states, Nebraska and South Dakota, might total more than $2 billion, he said.

The Pennsylvania corn crop is weathering a brutal season, and prices already are spiking upward, said John Yocum of the Penn State field station near Manheim, Lancaster County. In recent days the auction prices of sweet corn, the kind found on dinner tables, jumped from an average $2.50 per dozen to as much as $4.50.

Nature's scorched-earth policy also has been unkind to the animal-friendly field corn, of which Pennsylvania is the biggest supplier in the Northeast. Eventually, said Yocum, the poor quality of the corn now being stored could affect the milk yields of cows, thus driving up milk prices.

Statewide, last month was the seventh-driest July in more than 100 years. It was the sixth-driest in New Jersey, and the seventh-driest in the Northeast as a whole.

In fact, save for a period in late winter and spring when the local drought appeared to be lifting, the last 12 months have been exceptionally dry, said David Robinson, the New Jersey state climatologist and a Rutgers University professor.

The last six months of 2001 were the driest such period on record in Philadelphia, according to the National Weather Service. The record dates back to 1872.

"The aquifers of New Jersey have never recovered," said Robinson. And in Pennsylvania, where wells are drilled deeper underground, anxiety is on the rise.

"The thing that's a real concern to farmers now is whether their wells are going to fail," said Yocum. He said farmers might have to truck in water, "an additional expense just when you don't need it."

The Upstate New York reservoirs that supply drinking water via the Delaware River to much of the Philadelphia region have been falling precipitously but still have not reentered the "drought watch" trigger zone.

Robinson is convinced that the entire Northeast has been through a four-year drought, pointing out that in New Jersey, for example, below-normal precipitation has fallen in 35 of the last 49 months. (That spell began after the wettest six months on record.)

So what's behind it all?

Robinson believes this most recent nationwide dry spell began with an East Coast heat wave last August.

For reasons that no one can divine, the higher atmospheric pressures that set off that heat wave have persisted in some form or another across the eastern half of the country and into the Atlantic. The heavier air of high pressure keeps storms from forming in winter and blocks refreshing fronts in summer.

"It's... that rock in the stream that shuts off the cold air and shuts off the precipitation," the climatologist said.

The high pressure has been so strong, and so persistent, that it has induced a mild west-to-east flow across the country, he said.

The lack of precipitation almost certainly has been contributing to the high temperatures, LeComte said, and vice versa. When the ground is dry, the sun's energy isn't needed for evaporation, so it all goes to heating.

"The drought feeds on itself at some point," LeComte said. "There's less moisture to evaporate, the ground heats up, and the air dries out."

Meteorologists believe any pattern that hangs around this long is probably also tied to sea-surface temperatures in the Atlantic and Pacific.

Although the Equatorial Pacific is in a state of El Niño, in which temperatures are well above normal, LeComte said the dryness might be linked to cooler-than-normal waters off Baja California. He said researchers had found a correlation between those cool waters and dryness, but they don't understand why.

It is also possible, Robinson said, that all the heat and drought could be tied to volcanic ash, or lack thereof. In the past, veils of volcanic ash have led to lower temperatures, but the good news/bad news is that fewer recent eruptions has meant very little ash spewed into the atmosphere to obscure the sun in the last 10 years.

Whatever the causes, it appears the drought conditions will only get worse during the next several weeks.

Hurricane forecasters already have served notice that this will be a quiet hurricane season. While the folks in South Florida might be doing cartwheels, this is not helpful for the people of the Mid-Atlantic and Northeast, who could use the wet, juicy leftovers of tropical storms.

What's more, said Svoboda, droughts aren't what they used to be.

They're worse.

"We have many more people, and much more development putting a tremendous strain on a finite resource," he said.

Right now, he said, the drought isn't as bad as those of the 1930s and '50s. But, he noted, this one is not over yet.

"While the drought itself may not be unprecedented," he added, "our vulnerability to drought may be the highest it's ever been."

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