The Paris climate agreement and some nations, including the U.S, recognize certain geoengineering projects as potentially legitimate, but the legal status of technologies to deflect the sun's radiation is wholly undefined despite carrying geopolitical and moral risks.
Why it matters: Solar radiation management, in which the sun's light is reflected by mirrors or particles deployed in the atmosphere, could have terrible environmental and societal consequences. It could be weaponized and lead to conflict between nations. Even if the risks are overblown, merely talking about and conducting research into geoengineering may weaken support for limiting emissions via renewable energy and conservation, methods we know work. When geoengineering is presented to people as a potential solution to climate change, their support for mitigation measures falls.
Bottom line: We need responsible communication. Even if solar radiation management never becomes a physical reality, how it is portrayed by scientists, governments, and corporations could have a profound effect on how the world addresses climate change.
Other voices in the conversation:
- Janos Pasztor, climate policy expert and executive director, Carnegie Climate Geoengineering Governance Initiative: We aren't ready to engineer the climate
- Jane Long, energy and climate scientist: It's time to investigate geoengineering technologies
- David Keith, climate and energy researcher, Harvard University: Solar geoengineering needs at least another decade of research
- Matthew Watson, geoengineering researcher, University of Bristol: We need to be sure the geoengineering cure isn't worse than the disease