Cross posted from Prometheus: The Science Policy Blog

John Holdren has given his first interview since being confirmed as President Obama's science advisor. In it he suggests that the Obama Administration is ready to consider geoengineering via particulate injection into the upper atmosphere as well as air capture, citing new cost estimates. Here is an excerpt from the AP article:

John Holdren told The Associated Press in his first interview since being confirmed last month that the idea of geoengineering the climate is being discussed. One such extreme option includes shooting pollution particles into the upper atmosphere to reflect the sun's rays. Holdren said such an experimental measure would only be used as a last resort.

"It's got to be looked at," he said. "We don't have the luxury of taking any approach off the table."

Holdren outlined several "tipping points" involving global warming that could be fast approaching. Once such milestones are reached, such as complete loss of summer sea ice in the Arctic, it increases chances of "really intolerable consequences," he said.

Twice in a half-hour interview, Holdren compared global warming to being "in a car with bad brakes driving toward a cliff in the fog."

At first, Holdren characterized the potential need to technologically tinker with the climate as just his personal view. However, he went on to say he has raised it in administration discussions. . .

But Holdren noted that shooting particles into the air -- making an artificial volcano as one Nobel laureate has suggested -- could have grave side effects and would not completely solve all the problems from soaring greenhouse gas emissions. So such actions could not be taken lightly, he said.

Still, "we might get desperate enough to want to use it," he added.

Another geoengineering option he mentioned was the use of so-called artificial trees to suck carbon dioxide -- the chief human-caused greenhouse gas -- out of the air and store it. At first that seemed prohibitively expensive, but a re-examination of the approach shows it might be less costly, he said.

Air capture, less costly than originally thought, hmmm, sounds familiar to something I've read before.

For related content, see Andy Revkin's interview with John Holdren at the New York Times' DotEarth blog.