Scientists are slowly starting to get practical on geoengineering. Cooling the entire planet with stratospheric solar geoengineering could cost only 5 billion dollars per year. And opting for artificial clouds saving the Arctic with geoengineering could be as cheap as 24 million euros.
Now a group including renowned climatologists and leading geoengineering thinkers Ken Caldeira and David Keith tries to investigate ways to alleviate some of the (likely) unwanted side effects of Arctic solar geoengineering.

One idea for fighting global warming is to increase the amount of aerosols in the atmosphere, scattering incoming solar energy away from the Earth’s surface. But scientists theorize that this solar geoengineering could have a side effect of whitening the sky during the day. New research from Carnegie’s Ben Kravitz and Ken Caldeira indicates that blocking 2% of the sun’s light would make the sky three-to-five times brighter, as well as whiter. Their work is published June 1st in Geophysical Research Letters, a journal of the American Geophysical Union.