Abstract
Much of the work on the ethics of climate engineering over the last few years has focused on the front-end of the potential timeline for climate intervention. Topics have included the initial taboo on bringing the discussion of climate engineering into the open, guidelines to put in place before commencing research, and governance arrangements before first deployment. While this work is clearly important, the current paper considers what insights can be gleaned from considering the tail-end, that is, by using the requirement for future cessation as a criterion for any acceptable climate engineering strategy. After showing that time-limited interventions are a key part of the rhetoric of leading climate engineering advocates, the paper examines the implications of imposing a 'cessation requirement' on solar radiation management and carbon dioxide removal strategies. Consideration of a cessation requirement turns out to reveal a great deal about what ought to be happening now, before any decision to proceed with climate engineering deployment has been taken.