We must not let geoengineering be shaped behind closed doors. Climate justice demands an inclusive approach

As the world faces the challenges of the climate crisis and critical threshold levels or tipping points may be reached soon, a disputable idea is gaining momentum as a potential solution: solar geoengineering – the deliberate reflection of sunlight to cool the planet. Advocates argue it could buy us time. Critics warn of unknown risks. Some see it as a possible emergency break if temperatures spiral out of control. Others call it a dangerous distraction that undermines meaningful climate action.

Research into solar geoengineering is advancing, including exploration of techniques such as stratospheric aerosol injection, which would involve spraying tiny reflective particles into the upper atmosphere to mimic the cooling effect of volcanic eruptions, and marine cloud brightening, which aims to enhance the reflectivity of low-lying marine clouds. While stratospheric aerosol injection is not being conducted, these technologies are being studied with increasing urgency in the global north. In the global south, however, they remain largely invisible to public discourse and policymaking.