--> Is there nothing new under the sun? – Jesse Reynolds / international & technology environmental policy

Analogs for the governance of solar geoengineering

Originally published as part of the report Governance of the Deployment of Solar Geoengineering [PDF] from the Harvard Project on Climate Agreements.

Key Points:

  • Although solar geoengineering is sometimes characterized as unprecedented in ways that would cause its governance to be very difficult, if not impossible, it is not sui generis in its core challenging aspects.
  • Humanity has governed technologies and socio-economic phenomena – such as international monetary policy, nuclear technologies, activities in outer space, and food, energy, and water systems – that have similar characteristics.
  • These imply that governance of solar geoengineering deployment is feasible; that facilitative international institutions, limited international cooperation, side payments, coercion, and norms could achieve modest aims; and that participation of key states will be essential.
  • After a decade of much talk yet little research, belated and suboptimal solar geoengineering is an increasingly salient hazard.

Solar geoengineering is sometimes characterized as unprecedented in ways that would cause its governance to be very difficult, if not impossible. For example, geographer Mike Hulme writes that “world agreement on the desirable temperature setting is unattainable, and the mere attempt to reach such agreement is likely to unsettle international relations” and from this concludes that it would be “ungovernable.” (Hulme 2014, p. xiii) These observers often point further to solar geoengineering’s unduly technocratic character, possible premature or excessive deployment, and the need to maintain it for long time scales to prevent a “termination shock” caused by sudden and sustained cessation.

In some ways, solar geoengineering would indeed be novel. It could give states or – in principle – even nonstate actors the power to dramatically affect environmental conditions across the entire globe. However, in its core aspects that critics cite – international (dis)agreement, technocratic complexity, possible premature or excessive implementation, and long-term maintenance – solar geoengineering is not sui generis. Humanity has governed technologies and socio-economic phenomena with similar characteristics with some degrees of success. Here, I briefly describe four examples and offer lessons that can be drawn from them.

States’ leaders regularly act in ways that they know will have substantial impacts on other states. In general, such actions are not prohibited but instead managed through diverse governance arrangements. This is evident in the case of international monetary policy. Like climate, countries’ economies are complex, imperfectly understood, and important to their citizens’ well-being. Typically, political leaders set low-resolution objectives – such as maximum sustainable employment and stable prices – toward which appointed experts strive via various technical tools. These measures affect other states’ economies in fairly predictable ways, sometimes negatively so. States are highly asymmetrical in their capacities for international economic influence, and one of them could use monetary policy as a means to intentionally harm another, at least hypothetically. But this appears to not occur, probably because such efforts would be poorly targeted and have unacceptable collateral impacts. Furthermore, the lack of centralized international decision-making in monetary policy is notable. The most important institution – the International Monetary Fund (IMF) – neither sets global monetary policy nor constrains that of its members (apart from conditions on loans). Instead, it monitors economic conditions, conducts research, provides a forum for sharing information, offers advice, helps build capacity, and responds to crises.

Nuclear technologies constitute perhaps the most frequently suggested analogy for solar geoengineering. This is understandable. Some applications of each (nuclear power and solar geoengineering research) should arguably be promoted, while others (nuclear weapons and solar geoengineering deployment) might be warranted in extremis but could be harmfully used prematurely or in ways contrary to global norms. Nonproliferation of nuclear weapons has been reasonably effective, in large part through a facilitative international organization, the International Atomic Energy Agency (IAEA); side payments of assistance in developing nuclear power; the emergence, socialization, and internalization of norms; an acceptance of some states’ weapon capacities; and coercion by great powers of weaker states. Liability for transboundary harm from nuclear power accidents has also furthered its responsible development. Yet four states have acquired nuclear weapons outside the Nonproliferation Treaty’s bounds, indicating limits to what international cooperation, side payments, coercion, and norms can accomplish when essential security interests are at stake.

Another domain in which a select set of powerful countries could use high-leverage technologies to affect others is activates in outer space. When these began in the 1960s, some observers expressed fears that the superpowers would use space as a platform to reinforce their supremacy. Multilateral agreements with modest aims were able to prevent weapons of mass destruction in space, establish liability for harm, and coordinate satellite-based radionavigation systems. Furthermore, joint activities regarding the International Space Station contributed to the thawing of the Cold War. However, a treaty that prohibits the exploration and use of the moon and other celestial bodies without the international community’s approval failed to attract the participation of the key countries with space programs.

Although the need to maintain solar geoengineering post-deployment is a serious concern, modern societies rely on the continued operation of multiple complex systems, most obviously those of food, energy, and – in some locations – water. If one of these systems were to become and remain inoperative, the consequences would be grave. Nevertheless, both lay and elite observers seem confident that these systems are sufficiently maintained, secure, redundant, and resilient. This is not to belittle possible vulnerabilities, which have become evident in the past and should be expeditiously identified and addressed. Instead, my purpose is to highlight that long-term maintenance of complex international systems is not qualitatively new and has been successful.

Such technologies and socio-economic phenomena offer some guidance for solar geoengineering deployment. First, its governance – including maintaining it for long time scales – is not as unprecedented as it might seem and is arguably feasible. Second, governance’s objectives should be modest. It could include an international institution that is widely perceived as legitimate with functions like those of the IMF and the IAEA as well as a (likely informal) mechanism through which norms of restraint and nonpractice could develop.

Third, participation of key states is essential. A proposed agreement to prohibit solar geoengineering deployment in the absence of international consensus would probably be rejected by the very states most likely to implement it. Instead, an effort to prevent premature and excessive deployment would need to count as participants the most powerful states, which might need to be explicitly granted more authority than others in order to attract them. Additional states with the capacity to deploy – and interest in doing so – might need substantial side payments – such as participation in research, assurances of notification and consultation, and perhaps compensation for demonstrable harm – to bring them into the cooperative fold.

Finally, climate change poses substantial risks, but there is no indication that emissions cuts and adaptation will sufficiently control them. Solar geoengineering has the potential to greatly reduce climate change and does not face the same global collective action problems. Although concerns of premature and excessive deployment have lingered, after a decade of much talk yet little research, belated and suboptimal solar geoengineering is an increasingly salient hazard. Governance should therefore aim to not only reduce risks and manage challenges, but also facilitate solar geoengineering’s responsible research, development, and – if appropriate – use.

This essay draws in part from the presentations of Scott Barrett and David Victor at the research workshop on the governance of solar geoengineering deployment at Harvard University in September 2018, on which this volume is partly based. The author thanks them.


Hulme, Mike. 2014. Can Science Fix Climate Change? A Case against Climate Engineering. Polity Press. Available in part online.


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