Earth stands at a tipping point. As we fail to curtail emissions fast enough, our planet stares down a cascade of imminent, catastrophic, and irreversible disaster triggered by climate change. Yet a potent technology already exists to buy us more time: solar geoengineering. Through methods such as atmospheric aerosols, human-generated cirrus clouds, and solar sails, we humans can—at least in the short term—slow the Earth’s warming. Should we?

Award-winning science writer Thomas Ramge’s Dimming the Sun is his provocative, informative, urgent, and necessary exploration of this intriguing stopgap solution. Ramge shows us how the science works, what the risks are—both geophysical and political—and how the international community might come together to agree on and regulate a safe and effective plan for geoengineering. And while he identifies the unknowns about the technology that remain, he believes this very uncertainty demands our full attention. With time to avert the worst of climate change rapidly running out, he makes a forceful case that the most responsible course of action is to dramatically increase research on solar geoengineering now—before it’s too late.