If no rapid transition away from coal, methane and petroleum is on the cards, then Artificial Geo-Engineering, a dangerous and once-ostracized technology, becomes increasingly likely. It already has the blessing of the Intergovernmental Panel on Climate Change. The probable consequences are dystopian sci-fi. ‘Solar radiation management’ will bleach the sky white, cause tens of thousands of deaths from aerosol pollution, gash the ozone layer and interrupt vital climatic systems like the monsoon and the Gulf Stream. Some of these risks are even acknowledged by its advocates; the world’s leading geo-engineer, David Keith, admits that the closest analogue to Artificial Geo-Engineering is nuclear weapons. It is appropriate that the natural habitat of this technology is in Alberta. In the 2000s, Keith was teaching at the University of Calgary, where both the institution and city have become inextricably linked to the tar-sands industry. To commodify his dangerous expertise he founded a firm, Carbon Engineering, which counts Bill Gates and tar-sands tycoon Murray Edwards as its billionaire patrons. Keith and his fellow thinkers were ostracized as dangerous quacks only a decade ago, but have become respectable through their embrace by the likes of Harvard (where Keith now teaches) and Oxford. Like nuclear waste, or the gargantuan tailings lakes of the tar-sands industry, Artificial Geo-Engineering will require millennia-long management. Should the ‘climate shield’ ever fail, if a war or some other disaster interrupts the aerosol cannons, then the world would rapidly overheat. Such an amplified geo-engineered summer could be as devastating to Earth life as a nuclear winter.