As the impacts of climate change accelerate and global efforts to reduce greenhouse gas emissions fall short of targets, interest in climate engineering technologies has grown. However, these large-scale interventions in Earth's natural systems carry both immense promise and significant risks. To address the complex ethical issues surrounding climate engineering, UNESCO's World Commission on the Ethics of Scientific Knowledge and Technology has published its first comprehensive report on the topic.
The report examines a broad range of climate engineering approaches, which fall into two main categories. Carbon Dioxide Removal techniques aim to draw carbon out of the atmosphere, either through technological means like industrial-scale carbon capture or natural methods such as large-scale tree planting. Solar Radiation Modification (SRM) involves reflecting sunlight back into space, for example by injecting reflective aerosols into the stratosphere or increasing the reflectivity of surfaces on Earth.
While these technologies offer potential tools to address climate change, the UNESCO report raises several key ethical concerns. A primary issue is that pursuing climate engineering could undermine existing climate policies and divert critical funding and attention away from emissions reduction and climate adaptation efforts. There are also significant equity concerns, as the high costs of developing and deploying climate engineering technologies could exacerbate global inequalities between wealthy and developing nations.
The report also highlights the potential for climate engineering to be used for military or geopolitical purposes, underscoring the need for robust international governance frameworks. Perhaps most critically, there remain major knowledge gaps around the effectiveness and potential consequences of large-scale climate interventions. The report warns that deploying these technologies could trigger unforeseen chain reactions with substantial risks to human populations, ocean ecosystems, global temperature patterns, and biodiversity.
Given these uncertainties, the UNESCO experts emphasize that climate engineering technologies cannot yet be relied upon to significantly contribute to meeting climate targets. They stress that the primary goal of any climate engineering research program should be to better identify and reduce uncertainties around potential climate actions.
To address these ethical challenges, the report offers several key recommendations for the research and governance of climate engineering:
1. Nations have a legal obligation to prevent harm and must introduce legislation to regulate new forms of climate action.
2. Scientific research on climate engineering must adhere to clearly defined ethical standards consistent with international law.
3. Countries must consider the transboundary impacts of their climate engineering decisions.
4. Implementing climate engineering techniques on a global scale requires open and responsible collaboration between all countries, as well as constant monitoring.
5. Marginalized communities on the frontlines of climate disruption, who are most likely to be impacted, must be fully considered and involved in climate engineering policies.
UNESCO plans to share this report and its conclusions with its 194 Member States to ensure these critical ethical issues are taken into account during intergovernmental discussions at COP28 and beyond.
Gabriela Ramos, UNESCO's Assistant Director-General for Social and Human Sciences, emphasized that while all options should be considered to address the climate crisis, the deployment of climate engineering should not come at the expense of existing commitments under the Paris Agreement. She stressed the need for a clearly established ethical framework before pursuing these technologies.
Emma Ruttkamp-Bloem, Chair of UNESCO's World Commission on the Ethics of Scientific Knowledge and Technology, highlighted the potential risks of climate engineering, both in its interactions with the climate system and in exacerbating existing risks or introducing new ones. She called for a thorough understanding of the effects and ethical implications of these technologies before pursuing them further.
The UNESCO report serves as a crucial reminder that the debate around climate engineering must be both ethical and political, reflecting the conflicting interests between different regions and communities globally. As interest in these technologies grows, this comprehensive ethical perspective offers an important framework for assessing their risks and opportunities, and for developing responsible governance approaches.
As the world grapples with the escalating climate crisis, the UNESCO report provides a timely and essential contribution to the ongoing dialogue about potential technological solutions. It underscores the need for careful consideration, international cooperation, and robust ethical guidelines in exploring climate engineering as a complement to – but not a replacement for – aggressive emissions reductions and adaptation efforts.
