From Marc Gunther: Geoengineering: Time to get serious?

Imagine a fleet of 1,500 remote-controlled, wind-powered ships, sailing the world’s oceans, spewing salt water into the air to whiten clouds, so they block more of the sun and cool an overheating planet.

Or think of trillions of tiny mirrors, sent into orbit, to reflect the sun’s rays. Or artificial trees that suck a ton of carbon a day out of the atmosphere. Or iron filings, sprinkled on seas, to rapidly grow phytoplankton, which absorb CO2.

These emergency strategies for curbing global warming aren’t crazy schemes. Well, maybe they are crazy schemes. But serious people say we should start taking them seriously, as a last-ditch option to deal with the threat of catastrophic climate disruptions….

Quite a few of the relevant options, it seems, will make some use of biotechnology.