How it works: The idea here is to use satellite-guided sailing ships to crisscross the oceans, constantly spewing a fine stream of sea mist into the clouds.
Turns out particles, in this case the salt in the sea mist, will cause clouds to become denser, reflecting more sunlight back into space and keeping the planet cooler.
The novel ship design actually dates back nearly a century, when the German inventor Anton Flettner built one that crossed the Atlantic. The mist towers are hollow and rotate in the wind, acting as sails. It can cross the Atlantic faster than a conventional sail boat and do so without a crew. The power for the mist pumps is generated by the turbine under the hull.
Each ship would cost $2 or $3 million, making the entire program cost just a few billion dollars.
About 1500 ships would be needed to maintain current temperatures, according to John Latham, a scientist at the National Center for Atmospheric Research.
Beyond the machine: Like most scientists studying geoengineering, Latham said it is not a substitute for reducing greenhouse gas emissions as it does not address other problems associated with too much carbon dioxide.
He also said the idea, like most other geoengineering ideas, needs much more study before it’s deployed on a wide scale, as any other potential side effects are still unknown.