Abstract
In addition to carbon dioxide, it is becoming increasingly clear that there are numerous other potent agents of anthropogenic forcing (e.g. methane, ozone, black carbon) at work in the climate system today. The typical ethical framing of climate change has not yet accommodated this complexity. In addition, geoengineering has often been presented as a Plan B that would simply counter unintentional (and positive) anthropogenic forcing with intentional (and negative) anthropogenic forcing. This paper attempts to better address the complexity by outlining an ethical framework for reducing all anthropogenic forcing, a position it labels the 'climate imperative.' The paper considers geoengineering alongside various other anthropogenic forcing activities and discusses what the climate imperative would say about each of them. On this analysis, GHG and black carbon reductions remain a priority. At the same time, the framing reveals a significant ethical difference between geoengineering through solar radiation management and through carbon dioxide removal.