Climate Engineer States His Case on Nanoparticles
(David Keith is emerging as a leading proponent of "geoengineering" the planet, here's an excerpt of his reasoning on using nanoparticles over sulfer particles in the chemical soup that has become our skies -ed.)
Aerosols could be injected into the upper atmosphere to engineer the climate by scattering incident sunlight so as to produce a cooling tendency that may mitigate the risks posed by the accumulation of greenhouse gases.
Analysis of climate engineering has focused on sulfate aerosols. Here I examine the possibility that engineered nanoparticles could exploit photophoretic forces, enabling more control over particle distribution and lifetime than is possible with sulfates, perhaps allowing climate engineering to be accomplished with fewer side effects.
The use of electrostatic or magnetic materials enables a class of photophoretic forces not found in nature. Photophoretic levitation could loft particles above the stratosphere, reducing their capacity to interfere with ozone chemistry; and, by increasing particle lifetimes, it would reduce the need for continual replenishment of the aerosol.
(from Wikipedia: Description of above diagram: The electrostatic field (lines with arrows) of a nearby positive charge (+)causes the mobile charges in conductive objects to separate due to electrostatic induction. Negative charges (blue) are attracted and move to the surface of the object facing the external charge. Positive charges (red) are repelled and move to the surface facing away.)
To read more of Dr. Keith's 2010 paper: Proceedings of the National Academy of Sciences
Cartoon image created by Atmospheric Cartoons