Summary
This review examines the climate intervention techniques of stratospheric aerosol injection, marine cloud brightening, and carbon dioxide removal. While these methods can reduce global temperatures and help mitigate climate change, they carry risks such as altered precipitation, ozone depletion, ocean acidification, and uncertain long-term impacts. CO₂ removal faces cost and scalability challenges. The authors stress the need for global governance and interdisciplinary research to ensure safe, equitable application, especially for vulnerable countries in the Global South.
Abstract
Climate intervention (CI) techniques are strategies proposed to deliberately modify the Earth’s climate system to mitigate the adverse effects of climate change. In the growing concern about global warming, these techniques are emerging as potential complements to traditional mitigation and adaptation measures. This study aims to review the main CI techniques, such as the injection of stratospheric aerosols, brightening of marine clouds, and the carbon dioxide (CO₂) removal. The methodology adopted employs a comprehensive review of the state-of-the-art and reference works on the subject, assessing the effectiveness, risks, and challenges associated with each technique. The results show that the injection of stratospheric aerosols can reduce global temperature by increasing the Earth’s albedo but can yield adverse effects such as changes in precipitation regimes, stratospheric ozone depletion, impacts on the radiative balance, and ocean acidification. On the other hand, CO₂ removal techniques are seen as potential solutions for decarbonization, although they face challenges related to cost and efficiency on a large scale. It is concluded that, despite the viability of CI techniques, their long-term impacts present significant uncertainties. It also highlights the need for a global governance structure to avoid unilateral actions that could bring disproportionate risks, especially for more vulnerable countries such as the Global South. Further interdisciplinary studies are therefore recommended to ensure that these technologies are applied safely and fairly.
