‘Termination shock’: trust our expert warnings on geoengineering’s planetary risks | Raymond Pierrehumbert, Julia Slingo, Michael Mann and Valerie Masson-Delmotte

A group of prominent climate scientists issued a stark warning about the planetary risks associated with geoengineering technologies on June 19, 2026, urging a critical examination of these proposed "quick fixes." The scientists, including Raymond Pierrehumbert, Julia Slingo, Michael Mann, and Valerie Masson-Delmotte, expressed concern that geoengineering solutions are being presented as offsets for insufficient progress in reducing carbon emissions. They specifically highlighted solar geoengineering, which aims to reduce sunlight, as a prominent example of these technologies, while noting a broader range of "desperate schemes" proposed to counteract climate disruption caused by atmospheric carbon dioxide. The scientists framed the discussion around the potential for "termination shock," a scenario where the abrupt cessation of geoengineering interventions could lead to rapid and severe climate shifts. They emphasized that these technologies do not address the root cause of climate change, which is the accumulation of greenhouse gases, and carry significant uncertainties and potential unintended consequences. The call for discussion, published in The Guardian, underscores a growing debate about the ethical, environmental, and geopolitical implications of attempting to technologically manage the Earth's climate.