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									Posted on Fri, Sep. 23, 2005
Could science defeat hurricanes?
Theories for gutting storms abound, but reality usually intrudes

SCOTT DODD
Staff Writer


Another monster hurricane tearing toward the Gulf Coast. Millions of people on the run. Billions of dollars in damage predicted.

All leading to the question: Can't these storms be stopped?

It's a question scientists, not to mention people living in the path of hurricanes, have been asking for decades. After all, if we can put a
man on the moon, why can't we prevent a killer storm -- or at least slow it down a bit?

Researchers and zealous amateurs have hatched plenty of schemes, from shooting space-based heat rays to lining the coast with giant
windmills. But nothing looks promising for now.

The government did try one idea, called Project Stormfury. The plan: Drop silver iodide from airplanes into the outer rainbands of a
storm.

The goal was to create a new ring of convection to compete with a hurricane's eye and rob the storm of its power. For a decade starting
in 1961, scientists seeded clouds in four hurricanes. The storms weakened, so they thought it was working.

Then Hugh Willoughby came along. The former director of the government's Hurricane Research Division concluded that a natural
process called "eyewall replacement" often makes storms wobble in intensity. That phenomenon weakened Hurricane Rita somewhat
Thursday as it plowed toward Texas.

"If I were really astute," says Willoughby, now a professor at Florida International University, "I'd go out tonight and seed the clouds,
and when the winds drop I'd claim, `I saved Houston! For $50 million, I'll do it again.' "

So silver iodide is out. Other ideas over the years: dropping sponges from airplanes; blasting storms with a fleet of jet engines;
dragging icebergs from the North Pole to cool down the tropics.

Robert Simpson, a former director of the National Hurricane Center (and one of the guys the Saffir-Simpson storm scale is named
after), thought spreading an oil slick in front of a hurricane might work. The Soviets tested it over the Pacific Ocean in the 1970s. The
results were never disclosed.

There's even the all-purpose plan to stop everything from asteroids to aliens: Nuke 'em.

Willoughby has heard them all. He even helped come up with a few ideas himself, such as building fiberglass ducts to suck water
from the ocean floor and cool the Gulf Stream.

One drawback: That might kick off the next ice age.

"When you do this kind of mega-engineering," Willoughby says, "you might create a solution that comes back and bites you in the
backside."

Indeed, hurricanes exist for a reason. They help the Earth expel heat from the tropics, provide much-needed rain to parts of the United
States during late summer, and help cleanse polluted coastal ecosystems.

"I think we'll be able to modify them someday, but because of the uncertainty, we may not want to," said Ross Hoffman, an
atmospheric researcher at a Massachusetts firm.
His idea involves using satellites with mirrors to reflect solar radiation, thus changing wind patterns.

The National Oceanic and Atmospheric Administration has pretty much given up on influencing storms. So has the American
Meteorological Society, which concluded in 1998 that there is "no sound physical hypothesis" for trying it.

Scientists keep coming up with ideas, though. Robert Langer, a chemical engineer at the Massachusetts Institute of Technology, is
trying to create a substance that could be spread in front of a hurricane to absorb water vapor (a variation on Simpson's old oil-slick
idea).

"The biggest problem we've had is getting funding," Langer said.

"The government will spend $50 billion on recovery, and we could have helped them for a great deal less."

Willoughby says there are promising ideas out there -- if scientists can overcome the massive engineering problems.

Another suggestion he has heard: Drag a piece of fabric into a hurricane's path.

Again, it might work, he said. But it would need to be about the size of Mecklenburg County. And how would you get it in place?

"The suggestion I heard was, pull it with mini-subs," Willoughby said.

"You'd need a lot of mini-subs."

Hurricane Busters

The National Oceanic and Atmospheric Administration's Hurricane Research Division has studied several ideas for disrupting storms.
Here's what it says about them:

Coat the ocean with oil or another substance

A promising idea that could stop a storm from absorbing water vapor, thus weakening it. But scientists have yet to find a
chemical that can stay together in the rough seas of a tropical storm.

Cool the ocean surface with icebergs

A hurricane with a 30-mile-wide eyewall, moving at 10 mph, will cover 7,200 square miles of ocean in a day (that's an area
larger than Connecticut). Add in the uncertainty of the forecast track, and you'd need to cool a patch of water the size of
South Carolina. That's a lot of ice.

Suck the water out of a storm with a chemical

A Florida businessman proposed using a substance called "Dyn-O-Gel," a glop that would make raindrops lumpy and weaken
a storm's eyewall. The research division said the effect was too small -- it would take 37,000 tons of "Dyn-O-Gel," delivered
every 90 minutes or so, to be effective.

Nuke 'em

Probably the most persistent suggestion. There's no evidence it would work, though. A major hurricane releases as much heat
energy as a 10-megaton nuclear bomb exploding every 20 minutes -- or five times as much as the human race uses in an entire
year. So one bomb wouldn't do much. Plus, even if it worked, the radioactive fallout would have to go somewhere.


Scott Dodd

								
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