So PhysicsWorld has done a nice article on some of the ‘engineering’ solutions that might be available for tackling global warming.
Generally they are pretty ambitious global-scale plans to turn down the thermostat a bit, given the premise that either carbon dioxide emissions will not fall sufficiently or that, even if they did, the earth would still be too hot and something else will be needed. They fall into a few categories. First, there is the CO2-vac. Suck up that excess carbon dioxide using whatever technology you can make work. Secondly there is control of the earth’s surface. This might mean things like planting crops / forests that are a little more reflective to sunlight than current crops. And thirdly, there is control of the amount of sunlight that hits earth.