John's idea, which has not been fully tested, is to increase the number of water droplets in about 10% of the world's marine stratocumulus clouds. This could be accomplished by bolstering the number of tiny saltwater droplets that act as cloud condensation nuclei, meaning they would serve as centers for the production of additional droplets.
Such a process would make the clouds whiter, increasing their albedo, or ability to reflect solar radiation back into space. If the clouds' reflectivity could be boosted by a few percent (which could be amply achieved by doubling the droplet numbers), this would compensate for a doubling of carbon dioxide levels in the atmosphere and, at least in theory, produce a cooling that would compensate for global warming.
Friday, June 17, 2005
John Latham of the National Center for Atmospheric Research has a plan for global cooling. I ran across it in a letter to the current New Yorker. But it isn't new. Here's a web page from a year ago. There was also an article in the Guardian Unlimited last February.