Stratoshield:
Nathan Myhrvold explains how to save the planet
by Todd Bishop

October 14, 2009

Combat climate change by pumping liquid sulfur dioxide into the stratosphere through nozzles in a hose lifted more than 15 miles into the atmosphere using helium-filled balloons. As described by Myhrvold in an interview this week, the idea behind this "Stratoshield" would be to dim the sun in critical areas of the world by just enough to reduce or reverse the effects of global warming.

"We think it's a simple, relatively cost-effective, pretty practical way that you could intervene and cool Earth off enough to present disaster," Myhrvold said.

No, this is not a joke, or a plot from a bad science-fiction movie. In fact, Myhrvold is talking about the idea now because the Stratoshield and hurricane-stopper ideas are both documented in the new book, "SuperFreakonomics," the follow-up to the hit "Freakonomics" by Steven Levitt and Stephen Dubner.

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myhrvold must've taken some chem courses, but he needs to refresh his memory (& read up on acid rain at the same time):

Weighing the pros and cons of stratospheric geoengineering
By Jeremy Jacquot

October 22, 2009

The ideas may sound like science fiction, but some researchers are seriously considering what it would take to shoot sun-reflecting aerosols into the atmosphere to counter climate change. Fleets of small jet aircraft could fly into the lower stratosphere several times a day and release sulfur gas to produce planet-cooling sulfate aerosols. Or giant balloons made out of plastic could be equipped with long hoses and used to pump sulfur gas upwards into the atmosphere. As outlandish or downright laughable as these may sound, these schemes, or others very much like them, are currently the subject of vigorous debate among some of the world's leading researchers.

A serious take on the possibilities comes courtesy of a study published a few weeks ago in the journal Geophysical Research Letters. Its authors, led by Alan Robock of Rutgers University, weighed the costs, risks, and potential benefits associated with the injection of sulfate aerosols into the stratosphere using existing technologies. They found that, while stratospheric geoengineering would slow sea-level rise, keep global temperatures in check, and stop the melting of sea ice—at an annual cost of several billion dollars—it would also produce more droughts and worsen ozone depletion. And, crucially, it would do nothing to reverse ocean acidification.

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