Can hurricanes be stopped?

Dear Cecil: I’m curious if the idea of artificially altering hurricanes’ strength has any scientific validity. I seem to recall that the Navy gave it a try in the ‘70s, but that’s based on hazy memories of 11th-grade science class. HeyHomie, via the Straight Dope Message Board


Illustration by Slug Signorino

Cecil replies:

You’ve done your teacher proud, Homie: for a decade starting in the early 1960s, the Navy collaborated with the U.S. Weather Bureau on a hurricane-deterrence project called Stormfury. That wasn’t our first rodeo, though. Back in 1947, the government had tried to weaken a hurricane off the Atlantic coast by dropping dry-ice pellets on it from military planes. How’d it go? Well, the storm was heading out to sea prior to intervention, but then abruptly reversed course and struck land north of Savannah, Georgia. Likely a coincidence, it turned out, but you see how the optics weren’t exactly encouraging.

Fifteen years later, Project Stormfury sought to apply roughly the same scientific principle, replacing the dry ice with silver iodide. Storm clouds typically contain a lot of supercooled water — H²O molecules below the freezing point that nonetheless don’t form ice. The thinking went that if you could seed a hurricane with something that would cause the supercooled water to cohere into raindrops — dry ice, silver iodide, even just dust — this would release pent-up heat energy and disrupt the wall of thunderstorms that define the hurricane’s eye, thus slowing down the vortex of wind. In practice, a couple attempts showed signs of success, but further analysis suggested the hurricanes would’ve powered down on their own.

The project, meanwhile, raised the ire of Fidel Castro, who accused the U.S. of trying, essentially, to weaponize the weather. Admittedly there’s something a bit Strangelovian in the image of Navy fighter-bombers dumping chemical canisters into a hurricane. Couple that with an amped-up name like Stormfury, and I’ll grant it all seemed a bit nuts.

Well, that was then.

Now, consider the escalating costs of rebuilding American cities after more intense and more frequent hurricanes, well into the tens and hundreds of billions of dollars a pop — since 1980, the U.S. has spent $1.2 trillion on weather-related disasters. Consider, too, the compounded human misery. I’d submit we’re past the stage where nutty-sounding ideas can be dismissed out of hand. And the science behind some of these schemes is sound enough, including Stormfury-style seeding — nobody’s talking about nuking hurricanes anymore. (Well, almost nobody: pre-Katrina, one Air Force general was heard asking, “I’ve got the bombs to drop. Where do I go?” Cooler heads generally view any combo of radioactive material and unpredictable high-speed winds as a nutty idea too far.) Currently, two proposals have gained some buzz and, as important, some funding:

  • Marine cloud brightening, conceived by the British scientists John Latham and Stephen Salter, would use a fleet of pilotless yachts to spray microscopic droplets of seawater into clouds in hurricane-forming regions, causing them to reflect more sunlight back into space. This was originally dreamed up as a response to global warming; holding up a mirror to the sun, basically, would help restrain runaway temps down here. Hurricanes thrive on heat, so MCB (possibly combined with seeding) might dial them back too.
  • Salter, meanwhile, is behind another plan called the Salter Sink, a floating structure that uses the power of waves to pump warm water from the ocean’s surface down a 200-yard tube to mix with the colder water below. Since, again, hurricanes rely on warm water for energy, positioning a few hundred sinks in the storm-breeding stretches of the Atlantic could have a literally chilling effect on their occurrence. The concept’s still early days, but it’s received backing from the likes of Bill Gates, if that gives any sense of how plausible it looks on paper.

Scientifically legit though these ideas may be, they’ve got critics. A chief objection is the allegedly impractical scale you’d need to enact such projects on, and the daunting associated costs. (Proponents counter that it’s still cheaper than endless rebuilding.) There’s the good old “playing God” argument, of course, which is more of a philosophical hangup. But frankly God’s got nothing on American tort law, which is where the real obstacles to weather modification reside. As one Atlantic article put it, “The problem isn’t the science. It’s the lawyers.”

Picture it: A category 5 hurricane’s headed straight for New Orleans. Science intervenes, it wobbles off course and, as a category 3 or 4, hits Houston, now a city of two million plaintiffs. And that’s if the storm stays in U.S. waters. Say it makes landfall in Mexico — now you’ve got a full-blown (as it were) international incident.

Then there are even bigger concerns. Altering rainfall in the Atlantic via cloud brightening, for instance, could change weather patterns in South America, potentially drying up the Amazon rain forests. With the Salter Sink, meanwhile, we can only imagine what cycling that much ocean water around will do to the local ecology. You can computer-model this stuff all you want, but at some point somebody’ll have to pull the trigger and cross their fingers.

Cecil Adams

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