Toby Svoboda

If deployed, aerosol geoengineering (AG) could involve unfairness to both present and future parties. I discuss three broad risks of unfairness that an AG deployment policy might carry: (1) causing disproportionate harm to those least responsible for climate change, (2) burdening future parties with the costs and risks of AG, and (3) excluding some interested parties from contributing to AG decision-making. Yet despite these risks, it may be too hasty to reject AG deployment as a potential climate change policy. I argue that since it is very unlikely that a completely fair climate change policy will be pursued, we have ethical reason to prefer some “incompletely fair” policy. Given various facts about our world, it might be the case that some AG policy is ethically preferable to many other feasible climate change policies, even if AG carries deeply problematic risks of unfairness.

According to the “Lesser of Two Evils Argument,” deployment of solar radiation management (SRM) geoengineering in a climate emergency would be morally justified because it likely would be the best option available. A prominent objection to this argument is that a climate emergency might constitute a genuine moral dilemma in which SRM would be impermissible even if it was the best option. However, while conceiving of a climate emergency as a moral dilemma accounts for some ethical concerns about SRM, it requires the controversial claim that there are genuine moral dilemmas, and it potentially undermines moral action guidance in emergency scenarios. Instead, it is better to conceive of climate emergencies as situations calling for agent-regret. This alternative allows us coherently to hold that SRM may be morally problematic even if it ought to be deployed in some scenario.