Geoengineering 

The case for spraying (just enough) chemicals into the sky to fight climate change

If you think pumping the sky full of chemicals sounds like a weird way to fight climate change, you’re not alone. Solar geoengineering — the idea of injecting aerosols into the high atmosphere to reflect sunlight back into space and make for a cooler planet — is very controversial. And not just because it seems so offbeat.

Although geoengineering is not yet being deployed in the real world, past computer modeling studies have suggested it could produce unintended effects like droughts. Some have worried that it might create new climate inequities, worsening the weather in some regions even as it improves conditions in others. It’s incurred so much backlash that until recently it’s been taboo among scientists, and even today, much less attention is devoted to exploring this strategy than to cutting emissions.

But a study published this week in Nature Climate Change argues that the strategy could be highly successful — it’s all a matter of how much geoengineering we use. Yes, spraying a huge quantity of aerosols aimed at totally eliminating global warming can produce unwanted effects. Yet applying the right “dose” — just enough to cut global warming in half — could do the trick without causing negative side effects, the scientists say.