Digital Light Source/Getty By Catherine Brahic The pressure is on. If we want to save the planet from the worst effects of climate change, we need to get our greenhouse gas emissions to zero by 2070 – a target that requires immediate and drastic action. But our unbreakable addiction to fossil fuels makes this goal seem more and more unreachable. So what if there were another solution, some quick techno-fix that could let us burn our fuel but not our planet? Enter geoengineering: large-scale manipulations of the planet designed to clean up our mess. The ideas range from sucking carbon dioxide out of the atmosphere to deploying a stratospheric parasol that would bounce the sun’s warming rays back out into space. Some have been field-tested, or soon will be. But while most climate researchers agree geoengineering makes sense as a last resort, we need to ask: do we have the right to interfere with the planet on this scale? The answer might seem obvious: we’ve already done it. By chucking billions of tonnes of greenhouse gases into the atmosphere, humanity has put the planet’s thermostat on turbo-boost, melted the Arctic, and altered the seasons, large-scale weather systems and the ocean’s acidity. Why should reversing that be any different?