Mac Willners

The ‘Global Justice Argument’ posits an obligation to research solar geoengineering on the grounds that climate change is unjust and solar geoengineering offers the most effective means to reduce harm befalling climate-disadvantaged people. But even if those claims hold, the argument contains an important gap. As solar geoengineering cannot restore pre-injustice conditions, it at best serves as compensation. Hence, a version of the argument sensitive to rectificatory justice must show climate-disadvantaged groups do not reasonably reject solar geoengineering as compensation. Evidence in that regard is mixed; some groups reasonably reject solar geoengineering, whereas others reluctantly accept it. Consequently, the success of this version of the argument hinges on reconciling these conflicting attitudes. A version of the argument that is only sensitive to distributive concerns largely avoids this issue. But that version faces other difficulties and would, we contend, have limited practical implications.

Those who have asked who should compensate for harm due to solar geoengineering have been preoccupied with a version of the Polluter Pays Principle according to which compensatory obligations befall deployers of the technology. But there is an alternative (but not mutually exclusive) interpretation. According to it, non-deploying greenhouse gas emitters are liable to compensate for harm due to solar geoengineering since they have contributed to the circumstances rendering it an understandable response to the threat of climate change. Such an Emitter Pays Principle is normatively attractive, especially in cases where deployment is a venial act of self-defense.