Can We Have It Both Ways? On Potential Trade-Offs Between Mitigation and Solar Radiation Management

Many in the discourse on climate engineering agree that if deployment of solar radiation management (SRM) technologies is ever permissible, then it must be accompanied by far-reaching mitigation of greenhouse gas (GHG) emissions. This raises the question of if and how both strategies interact. Although raised in many publications, there are surprisingly few detailed investigations of this important issue. The paper aims at contributing to closing this research gap by (i) reconstructing moral hazard claims to clarify their aim, (ii) offering one specific normative justification for far-reaching mitigation and (iii) investigating in greater detail different mechanisms that could potentially cause a trade-off between mitigation and SRM. I conclude that the empirical evidence questioning the trade-off hypothesis is inconclusive. Moreover, theoretical reflections as well as economic model studies point to a trade-off. In our current epistemic situation these findings must be taken seriously. They caution against researching and developing SRM technologies before measures to avoid or minimise a trade-off are implemented.