The Paris Agreement stipulates that global warming be stabilized at well below 2 °C above pre-industrial levels, with aims to further constrain this warming to 1.5 °C. However, it also calls for reducing net anthropogenic greenhouse gas (GHG) emissions to zero during the second half of this century. Here, we use a reduced-form integrated assessment model to examine the consistency between temperature- and emission-based targets. We find that net zero GHG emissions are not necessarily required to remain below 1.5 °C or 2 °C, assuming either target can be achieved without overshoot. With overshoot, however, the emissions goal is consistent with the temperature targets, and substantial negative emissions are associated with reducing warming after it peaks. Temperature targets are put at risk by late achievement of emissions goals and the use of some GHG emission metrics. Refinement of Paris Agreement emissions goals should include a focus on net zero CO2—not GHG—emissions, achieved early in the second half of the century.
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Geden, O. An actionable climate target. Nat. Geosci. 9, 340–342 (2016).
Azar, C., Johansson, D. J. A. & Mattsson, N. Meeting global temperature targets—the role of bioenergy with carbon capture and storage. Environ. Res. Lett. 8, 034004 (2013).
Rogelj, J. et al. Energy system transformations for limiting end-of-century warming to below 1.5 °C. Nat. Clim. Change 5, 519–527 (2015).
Rogelj, J. et al. Zero emission targets as long-term global goals for climate protection. Environ. Res. Lett. 10, 105007 (2015).
Hallegatte, S. et al. Mapping the climate change challenge. Nat. Clim. Change 6, 663–668 (2016).
Sanderson, B. M., O’NeillB. C. & Tebaldi, C. What would it take to achieve the Paris temperature targets? Geophys. Res. Lett. 43, 7133–7142 (2016).
Schleussner, C.-F. et al. Science and policy characteristics of the Paris Agreement temperature goal. Nat. Clim. Change 6, 827–835 (2016).
Robiou du Pont, Y. et al. Equitable mitigation to achieve the Paris Agreement goals. Nat. Clim. Change 7, 38–43 (2017).
Su, X. et al. Emission pathways to achieve 2.0 and 1.5 °C climate targets. Earth’s Future 5, 592–604 (2017).
Wigley, T. M. L. The Paris warming targets: emissions requirements and sea level consequences. Climatic Change https://doi.org/10.1007/s10584-017-2119-5 (2017).
Tanaka, K., Johansson, D. J. A., O’Neill, B. C. & Fuglestvedt, J. S. Emission metrics under the 2 °C climate stabilization target. Climatic Change 117, 933–941 (2013).
Tanaka, K. et al. Aggregated Carbon Cycle, Atmospheric Chemistry, and Climate Model (ACC2) – Description of the Forward and Inverse Modes 188 (Max Planck Institute for Meteorology, 2007).
Riahi, K., Grübler, A. & Nakicenovic, N. Scenarios of long-term socio-economic and environmental development under climate stabilization. Technol. Forecast. Soc. Change 74, 887–935 (2007).
IPCC Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) (Cambridge Univ. Press: 2013).
Tanaka, K., Peters, G. P. & Fuglestvedt, J. S. Policy update: multicomponent climate policy: why do emission metrics matter? Carbon Manag. 1, 191–197 (2010).
Tol, R. S. J., Berntsen, T. K., O’Neill, B. C., Fuglestvedt, J. S. & Shine, K. P. A unifying framework for metrics for aggregating the climate effect of different emissions. Environ. Res. Lett. 7, 044006 (2012).
Allen, M. R. et al. New use of global warming potentials to compare cumulative and short-lived climate pollutants. Nat. Clim. Change 6, 773–776 (2016).
O’Neill, B. C. Economics, natural science, and the costs of global warming potentials. Climatic Change 58, 251–260 (2003).
Johansson, D., Persson, U. & Azar, C. The cost of using global warming potentials: analysing the trade off between CO2, CH4 and N2O. Climatic Change 77, 291–309 (2006).
Matthews, H. D. & Caldeira, K. Stabilizing climate requires near-zero emissions. Geophys. Res. Lett. 35, L04705 (2008).
Rogelj, J., Meinshausen, M., Schaeffer, M., Knutti, R. & Riahi, K. Impact of short-lived non-CO2 mitigation on carbon budgets for stabilizing global warming. Environ. Res. Lett. 10, 075001 (2015).
Pierrehumbert, R. T. Short-lived climate pollution. Annu. Rev. Earth Planet. Sci. 42, 341–379 (2014).
Field, C. B. & Mach, K. J. Rightsizing carbon dioxide removal. Science 356, 706–707 (2017).
Hooss, G., Voss, R., Hasselmann, K., Maier-Reimer, E. & Joos, F. A nonlinear impulse response model of the coupled carbon cycle-climate system (NICCS). Clim. Dynam. 18, 189–202 (2001).
Bruckner, T., Hooss, G., Füssel, H.-M. & Hasselmann, K. Climate system modeling in the framework of the tolerable windows approach: the ICLIPS climate model. Climatic Change 56, 119–137 (2003).
Tanaka, K., Raddatz, T., O’Neill, B. C. & Reick, C. H. Insufficient forcing uncertainty underestimates the risk of high climate sensitivity. Geophys. Res. Lett. 36, L16709 (2009).
Tanaka, K., Raddatz, T. Correlation between climate sensitivity and aerosol forcing and its implication for the ‘climate trap’. Climatic Change 109, 815–825 (2011).
Joos, F. et al. Carbon dioxide and climate impulse response functions for the computation of greenhouse gas metrics: a multi-model analysis. Atmos. Chem. Phys. 13, 2793–2825 (2013).
Johansson, D. Temperature stabilization, ocean heat uptake and radiative forcing overshoot profiles. Climatic Change 108, 107–134 (2011).
van Vuuren, D. P., Weyant, J. & de la Chesnaye, F. Multi-gas scenarios to stabilize radiative forcing. Energy Econ. 28, 102–120 (2006).
Walsh, B. et al. Pathways for balancing CO2 emissions and sinks. Nat. Commun. 8, 14856 (2017).
The authors thank D. Johansson for providing data associated with the maximum abatement cost curves used in this study. The authors are grateful for comments from B. Sanderson, X. Su, C. Tebaldi and T. Wigley, which were useful to improve this study. This research was partially supported by the Environment Research and Technology Development Fund (2-1702) of the Environmental Restoration and Conservation Agency, Japan.
The authors declare no competing interests.
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Tanaka, K., O’Neill, B.C. The Paris Agreement zero-emissions goal is not always consistent with the 1.5 °C and 2 °C temperature targets. Nature Clim Change 8, 319–324 (2018). https://doi.org/10.1038/s41558-018-0097-x
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