"Interest in CO2 may generate or reinforce a lasting interest in national or international means of climate and weather rmodification [geoengineering]; once generated, that interest may flourish independent of whatever is done about CO2."A few people were thinking about geoengineering even then.
-- Thomas Schelling, economist and Nobel Laureate, in the 1983 National Academy of Sciences study of climate change
And no, Keith isn't advocating we do this. Not at this time. His book is, I think, very intellectually honest on the subject of climate engineering, examining it from all angles. He doesn't give only the pros while leaving out the cons.
Nor does he suggest we begin geoengineering soon. But he does think we should immediate begin serious and comprehensive research into the idea(s), leading to small-scale experiments, and that the world should establish international governing bodies that would make decisions and regulate any geoengineering experiments or full-scale projects.
Keith doesn't even think we should do enough geoengineering to competely stop global warming -- he advocates only enough to halt half the warming, with emissions cuts doing the other half. Ultimately, he says, the world must transition to a carbon-free economy.
It's an interesting little book. Keith has thought about this subject as much as anyone, and makes arguments I hadn't seen anywhere else.