Eli Kintisch has an interesting scoop over at Science's website. Last week, a group of 50 top climate scientists met, behind closed doors, to discuss the possibility of geo-engineering as a way to stave off global warming. Mysteriously, only three publications were allowed to attend (Science, Nature, and The New York Times). And the results… weren't what anyone expected.

Most scientists have long dismissed geo-engineering schemes as crazy and dangerous—ideas like putting aerosols into the stratosphere to cool the planet, or modifying the ocean's albedo. The climate, after all, is very complex, trying to meddle with it further could really muck things up, and just talking about this stuff might divert attention away from the task of curbing CO2 emissions. But now, according to Kintisch, a growing number of climate scientists are so spooked by global warming, and the fact that most nations aren't doing enough to prevent it, that they've decided it would be crazy and dangerous not to look into geo-engineering.

The best overviews I've seen on this issue are this Boston Globe article and this Wilson Quarterly piece. But just to pile on: It's worth noting that no one has yet come up with an even halfway plausible geo-engineering plan. The most promising idea to date—injecting sulfuric dust into the atmosphere to reflect sunlight—suffered a blow after two University of Colorado scientists pointed out that it could wreak havoc on global rainfall patterns. More research would be fantastic, but it'd be insane for the world to sit around and wait for geo-engineering to save us, only to discover that, 20 years hence, none of these wacky plans have made it past the bong-cloud stage, and we're still on our present, carbon-belching energy path.

There's also the question of who would control the weather. Cloud-seeding in the United States has led to all sorts of lawsuits from farmers complaining about stolen rain. Chinese cities experimenting with this stuff are now warring over "cloud theft." The U.S. Air Force has drafted a report, "Weather as a Force Multiplier," discussing ways to use weather-modification as a weapon. If someone does come up with a way to cool the earth—say, giant space mirrors—there would be all sorts of tricky debates about who decides how it's used. It's hard to imagine that the international talks over that would be any less difficult than reaching an agreement on reducing carbon emissions.

--Bradford Plumer