Abstract This paper responds to a comment on our study of national “temperature neutrality” (TN) as a basis for climate policy, using Ireland as a case study. The comment mischaracterises our original analysis in several respects; we correct these mischaracterisations and engage with the substantive arguments raised. We demonstrate that the comment constructs a false dichotomy between national TN and net-zero greenhouse gas emissions (NZ-GHG), overlooking the split-gas compromise pathways explicitly evaluated in our original study. In addition, the EU effort-sharing framework is based on absolute GHG emissions reductions, not temperature contributions, and Ireland’s obligations under Regulation (EU) 2018/842 and the Paris Agreement require economy-wide absolute reductions. A national TN approach is therefore incompatible with these existing frameworks. We further show that widespread adoption of national TN would create a proliferation dynamic, a “race to the bottom”, in which the mitigation gap left by TN-adopting states increases pressure on remaining states, collectively undermining the EU and global mitigation effort. We also rebut the assertion that GWP100 lacks scientific rigour: it is grounded in the same physical climate modelling as TN-based approaches and benefits from a standardised, internationally accepted accounting protocol. Finally, we highlight the equity implications identified in our original study: national TN grandfathers disproportionately high per-capita agricultural CH 4 emissions in Ireland, appropriating emissions space needed by food-insecure developing countries. We conclude that TN is not an effective, fair, transparent, or robust basis for national climate policy.
Duffy et al. (Tue,) studied this question.