A group of leading climate scientists has issued a stark warning about the dangers of solar geoengineering, arguing that such interventions could lead to a catastrophic 'termination shock' if ever halted. In a Guardian article, Raymond Pierrehumbert, Julia Slingo, Michael Mann, and Valerie Masson-Delmotte caution that these techno-optimistic 'quick fixes' are no substitute for cutting carbon emissions.
The scientists explain that carbon dioxide remains in the atmosphere for millennia, while the effects of solar geoengineering—such as injecting substances to reflect sunlight—decay within years. They note that building the necessary infrastructure could take two decades, after which the world would become reliant on its maintenance. If circumstances forced a cessation, the pent-up warming would be released rapidly, causing a 'termination shock'.
Other geoengineering schemes, including proposals to dam the Bering Strait, also require sustained maintenance over centuries. The authors stress that such long-term commitments are risky in a world prone to conflict and unforeseen events. They argue that geoengineering does not 'buy time' for decarbonisation but instead puts the planet in a precarious state.
The scientists, who collectively have over 100 years of climate research experience, highlight the lack of rigorous modelling for solar geoengineering scenarios. They note that existing models disagree on the required level of intervention and the likely response. They call for the same scientific diligence applied to understanding greenhouse gas impacts before pursuing geoengineering.
