Environmental Visionaries: The Big Gun
David Keith believes strong-arm strategies could soon be our last resort for reversing record levels of carbon in the atmosphere In the 1992 film Unforgiven, Clint Eastwood spends most of the movie slowly and methodically avoiding violent confrontation with the bad guys before finally turning things around with a bloody burst of gunslinging. That's something like the approach of Canadian physicist and environmental scientist David Keith. Except that his villain is climate change, and while he's still doing everything he can to avoid a fight, Keith is also stockpiling ammo. "If we do the job we should be doing on cutting emissions, and we are lucky, we won't need geoengineering," says Keith, a professor at the University of Calgary whose start-up company, Carbon Engineering, is developing commercial-scale devices to capture atmospheric carbon dioxide. That's the slow and methodical. "But if we can't control atmospheric CO2 well enough, then we might want to...