The Economist: Solar geoengineering is becoming a respectable idea
November 23, 2023 The World Climate Research Programme’s Open Science Conference, held roughly every decade, has witnessed a significant evolution in discourse over the years, particularly regarding geoengineering—a deliberate manipulation of Earth’s climate to counteract global warming. Dr. Jim Hurrell, a climate scientist and WCRP member, notes that discussions around geoengineering were virtually absent in 2011 but took center stage in the recent conference held in Rwanda. This shift in focus reflects a broader change in perception. While geoengineering was previously disregarded by environmental groups and politicians, it has gained attention in various reports, including those from the European Commission, the American government, and the United Nations. This newfound interest stems from the failure to sufficiently reduce greenhouse gas emissions, prompting a reassessment of the potential risks and benefits of solar geoengineering (SRM). Solar geoengineering aims to reduce the amount of sunlight reaching Earth’s surface by increasing the planet’s albedo, which reflects sunlight back into space. This approach draws inspiration from natural phenomena like volcanic eruptions, which temporarily cool the planet by releasing light-scattering particles into the atmosphere. Despite its potential cost-effectiveness compared to decarbonization efforts, SRM raises significant concerns. These include potential disruptions to weather patterns and stratospheric chemistry, as well as the exacerbation of existing environmental issues like ocean acidification. Moreover, SRM’s affordability could lead to geopolitical tensions if deployed without global consensus. Critics also warn of a “moral hazard,” suggesting that reliance on SRM could undermine efforts to reduce greenhouse gas emissions. Nonetheless, proponents argue that geoengineering could provide a temporary solution while emissions reduction strategies are implemented—a concept referred to as “peak shaving.” The controversy surrounding SRM is reflected in recent events, such as the cancellation of an experimental test in Sweden due to environmental concerns and an unauthorized experiment by an American startup in Mexico. Additionally, over 400 academics have called for an international non-use agreement on SRM research and deployment. Despite these challenges, there is growing interest among policymakers and experts in exploring the potential of SRM, driven in part by the urgency of addressing climate change. Poor countries, facing the most severe consequences of rising temperatures, are particularly open to considering geoengineering as a last resort. While debates continue, there is a consensus emerging around the need for a comprehensive research program to assess the feasibility and implications of SRM. Such efforts, if conducted transparently and collaboratively, could inform future climate policy decisions and offer insights into alternative approaches to combating global warming.