We have a decade to sort out a big chunk of our carbon pollution problem. If we fail to do so, our chances at protecting the climate that allowed humans to thrive will slip away. That could lead to world leaders or a rogue billionaire taking the rather extreme measure of blocking the sun to cool things down. This isn’t some Lex Luther super villain idea, it’s something scientists are actively studying so we don’t dive headlong into a huge planetary experiment blind.
The process known as solar radiation management (or SRM if you really want to geek out) is the most intensely planet-altering form of a broader set of unproven tools that fall under the banner of geoengineering. It would require injecting sun-reflecting particles in the Earth’s stratosphere in its most basic form or, if you’re a tech-loving former presidential candidate, deploying space mirrors. The idea has a certain seduction. It’s cheap (space mirrors aside). Though no humans have tested it, we know it would definitely cool things down based on what scientists have learned from studying volcanoes. And the alternative of unchecked climate change if we don’t get our act together isn’t exactly appealing.
But there are also plenty of issues, including not knowing the exact impacts it would have on other parts of the climate and the fact we may not being able to stop. The relative cost of a couple billion dollars a year really does mean, say, a bald billionaire who raked in $28 billion during the pandemic alone could do it. For a rogue state desperate for relief from the heat, there’s even more incentives to give it a go. https://earther.gizmodo.com/no-we-shouldnt-just-block-out-the-sun-1843043812