"If I may," said the lord mayor, "we have looked at this. Oh, England’s not big enough. Canada maybe. The scale of the program would be spectacularly enormous, and it would by its very nature have to be distributed over a significant part of the earth’s surface. Many jurisdictional boundaries crossed. Many nations would have to cooperate just so. And once the plants have grown and stored up all that biomass, you can’t allow the carbon to find its way back into the atmosphere, or else what’s the point? You basically have to chop down the forests, stack up the wood somewhere safe, make sure it never catches fire, and then start growing a whole new forest."