Aluminum as Aerosol Geoengineering Agent
Some foods have the power to leach aluminum out of tin foil. If foods can do this, just think of what aluminum can do to your soft tissues inside your body when you breathe it in.
Andrew Maynard from the Institute of Ethics and Emerging Technologies (IEET) referring to David Keith’s scheme says, “In a nutshell, David’s idea is to engineer discs around 10 micrometers across and 50 nanometers thick, with a core of aluminum, a top layer of aluminum oxide, and a bottom layer of barium titanate. Injected high enough into the atmosphere (so Brownian motion didn’t muck things up) the discs should align with the lighter aluminum/aluminum oxide side facing up, and the heavier barium titanate side facing down. This is important, because the way these two surfaces interact with air molecules when the particles heat up – as they would do in sunlight – means that there would be a net force pushing the discs up (photophoresis). In effect, the particles would levitate to a stable position in the atmosphere, while keeping their shiny side to the sun – thus reflecting sunlight away from the earth (or increasing albedo). http://ieet.org/index.php/IEET/more/maynard20100917