Members’ Publications

Scenarios towards limiting global mean temperature increase below 1.5°C

Authors
Rogelj J., Popp A., Calvin K. V., Luderer G., Emmerling J., Gernaat D., Fujimori S., Strefler J., Hasegawa T., Marangoni G., Krey V., Kriegler E., Riahi K., van Vuuren D. P., Doelman J., Drouet L., Edmonds J., Fricko O., Harmsen M., Havlík P., Humpenöder F., Stehfes E., Tavoni M.
Journal
Nature Climate Change
DOI
10.1038/s41558-018-0091-3
Abstract

The 2015 Paris Agreement calls for countries to pursue efforts to limit global-mean temperature rise to 1.5°C. The transition pathways that can meet such a target have not, however, been extensively explored. Here we describe scenarios that limit end-of-century radiative forcing to 1.9Wm−2, and consequently restrict median warming in the year 2100 to below 1.5°C. We use six integrated assessment models and a simple climate model, under different socio-economic, technological and resource assumptions from five Shared Socio-economic Pathways (SSPs). Some, but not all, SSPs are amenable to pathways to 1.5°C. Successful 1.9Wm−2 scenarios are characterized by a rapid shift away from traditional fossil-fuel use towards large-scale low-carbon energy supplies, reduced energy use, and carbon-dioxide removal. However, 1.9Wm−2 scenarios could not be achieved in several models under SSPs with strong inequalities, high baseline fossil-fuel use, or scattered short-term climate policy. Further research can help policy-makers to understand the real-world implications of these scenarios.