Cain, MichelleJenkins, StuartAllen, Myles R.Lynch, JohnFrame, David J.Macey, Adrian H.Peters, Glen P.2021-12-072021-12-072021-12-06Cain M, Jenkins S, Allen MR, et al., (2022) Methane and the Paris Agreement temperature goals. Philosophical Transactions A: Mathematical, Physical and Engineering Sciences, Volume 380, Issue 2215, January 2022, Article number 202004561364-503Xhttps://doi.org/10.1098/rsta.2020.0456http://dspace.lib.cranfield.ac.uk/handle/1826/17315Meeting the Paris Agreement temperature goal necessitates limiting methane (CH4)-induced warming, in addition to achieving net-zero or (net-negative) carbon dioxide (CO2) emissions. In our model, for the median 1.5°C scenario between 2020 and 2050, CH4 mitigation lowers temperatures by 0.1°C; CO2 increases it by 0.2°C. CO2 emissions continue increasing global mean temperature until net-zero emissions are reached, with potential for lowering temperatures with net-negative emissions. By contrast, reducing CH4 emissions starts to reverse CH4-induced warming within a few decades. These differences are hidden when framing climate mitigation using annual ‘CO2-equivalent’ emissions, including targets based on aggregated annual emission rates. We show how the different warming responses to CO2 and CH4 emissions can be accurately aggregated to estimate warming by using ‘warming-equivalent emissions', which provide a transparent and convenient method to inform policies and measures for mitigation, or demonstrate progress towards a temperature goal. The method presented (GWP*) uses well-established climate science concepts to relate GWP100 to temperature, as a simple proxy for a climate model. The use of warming-equivalent emissions for nationally determined contributions and long-term strategies would enhance the transparency of stocktakes of progress towards a long-term temperature goal, compared to the use of standard equivalence methods. This article is part of a discussion meeting issue ‘Rising methane: is warming feeding warming? (part 2)’.enAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/methaneclimateemission metricsmitigationArticle