349. LOCALIZED GEOENGINEERING
There is a misconception that geoengineering can only be applied to the entire earth. This is not really true.
In a recent Tech Talk at Google (available as a youtube video here -- well worth watching as an intro to geoengineering), Stanford University climate scientist Ken Caldeira asks the following question (at around 29:00):
Geoengineering the whole earth is a little scary. Would regional scale geoengineering be possible?He then shows some modeling and analysis of localized applications of aerosol over the north pole, where the current warming is having its most dramatic effect. He concludes: "More or less, it's within our technical capability to make however much sea ice we want." (33:30)
The idea of localized cooling is nothing new. In fact, mainstream climate science recognizes that man-made aerosols (which caused the cooling period from 1940-1970) have localized effects. In other words, humans have already done decades-long localized geoengineering to cool the northern hemisphere. We just didn't realize we were doing it at the time.
Localized heating (perhaps to generate precipitation or clouds) is also within human technical capabilities using space mirrors. That may sound futuristic, but it's not. There are numerous mirrors already in space (in telescopes and imaging systems), and the USSR actually deployed a large space mirror to illumine the dark side of the earth 15 years ago in 1993 (Znamya 2).
These measures are not as expensive as you might think. Here's UC-Irvine physics professor Gregory Benford on the subject:
"The cost to spray particles over the Arctic would be a couple hundred million dollars a year; and for the whole planet, it's a few billion a year," Benford says. "That's the thing that terrifies geoengineering's opponents -- that this is at least a thousand times cheaper than anything else."SourceWith that in mind, let me conclude with a tough question that Ken Caldeira is fond of asking:
"Which is more environmentally sensitive, to let the polar bears go extinct or put some dust in the upper atmosphere?"