Impact of methane and black carbon mitigation on forcing and temperature: a multi-model scenario analysis
Smith S.J., Chateau J., Dorheim K., Drouet L., Durand-Lasserve O., Fricko O., Fujimori S., Hanaoka T., Harmsen M., Hilaire J., Keramidas K., Klimont Z., Luderer G., Moura M.C.P., Riahi K., Rogelj J., Sano F., van Vuuren D.P., Wada K., (2020), Impact of methane and black carbon mitigation on forcing and temperature: a multi-model scenario analysis, Climatic Change, (2020), DOI: 10.1007/s10584-020-02794-3, webpage
The relatively short atmospheric lifetimes of methane (CH4) and black carbon (BC) have focused attention on the potential for reducing anthropogenic climate change by reducing Short-Lived Climate Forcer (SLCF) emissions. This paper examines radiative forcing and global mean temperature results from the Energy Modeling Forum (EMF)-30 multi-model suite of scenarios addressing CH4 and BC mitigation, the two major short-lived climate forcers. Central estimates of temperature reductions in 2040 from an idealized scenario focused on reductions in methane and black carbon emissions ranged from 0.18–0.26 °C across the nine participating models. Reductions in methane emissions drive 60% or more of these temperature reductions by 2040, although the methane impact also depends on auxiliary reductions that depend on the economic structure of the model. Climate model parameter uncertainty has a large impact on results, with SLCF reductions resulting in as much as 0.3–0.7 °C by 2040. We find that the substantial overlap between a SLCF-focused policy and a stringent and comprehensive climate policy that reduces greenhouse gas emissions means that additional SLCF emission reductions result in, at most, a small additional benefit of ~ 0.1 °C in the 2030–2040 time frame.