As the world grapples with the slow progress of greenhouse gas emission reductions, a recent modeling study has ignited fresh concerns regarding the unpredictability of solar geoengineering.
As the world grapples with the slow progress of greenhouse gas emission reductions, a recent modeling study has ignited fresh concerns regarding the unpredictability of solar geoengineering. This study calls into question our ability to reliably manage the outcomes of this approach, which aims to mitigate the impacts of climate change by artificially reducing the amount of solar radiation reaching the Earth’s surface.
Solar geoengineering, a method akin to mimicking the cooling effects observed after volcanic eruptions, appears promising in theory, especially as current efforts to limit greenhouse gas emissions fall short of curbing global temperature rise within safe limits.
However, since its inception into mainstream scientific discourse, geoengineering strategies have been a contentious topic, evoking varied reactions ranging from viewing it as a threat to climate action to considering it a necessary measure.
The recent study, which modelled the regional effects of injecting sulfur aerosols into the tropical stratosphere, utilized a comprehensive global aerosol-chemistry climate model. The findings unveiled startling revelations, indicating that the adverse effects of such interventions could rival those of climate change itself in certain regions.
These effects include significant warming in the upper atmosphere above the tropics, alterations in large-scale weather patterns, intensified surface warming in polar regions, and modifications in regional precipitation patterns over land, thereby failing to entirely mitigate warming in high northern latitudes.
Helene Muri, from the Norwegian University of Science and Technology, underscores a key finding of the study, highlighting the significant contribution of low-latitude aerosols’ absorption of longwave radiation to unintended consequences, such as regional warming.
Moreover, the study’s authors suggest potential mitigative measures, such as utilizing less absorptive materials or implementing more sophisticated injection strategies. However, Andrew Lockley, an independent researcher, emphasizes the necessity of deploying aerosols optimized in size and material to minimize stratospheric heating, thereby enhancing the efficacy of geoengineering efforts.
Lockley stresses the importance of bridging modelling outcomes with real-world data to gain a comprehensive understanding of the actual impacts. He advocates for early experiments to grasp the fate of injected aerosols in the atmosphere and their ensuing thermal and dynamical effects.
Despite the insights gleaned from modelling studies, Olaf Corry, a political scientist at the University of Leeds, warns against overlooking the complexities of implementing large-scale interventions across national boundaries. Corry asserts that while modelling offers valuable insights, it often fails to account for practical challenges and geopolitical considerations inherent in such endeavors.
In essence, the study underscores the inherent risks and uncertainties associated with solar geoengineering, both in terms of its geophysical impacts and its political ramifications. As discussions around geoengineering continue, it becomes imperative to balance scientific advancements with a nuanced understanding of the real-world complexities involved, ensuring that potential solutions do not inadvertently exacerbate existing challenges in the fight against climate change.