The Paris Agreement zero-emissions goal is not always consistent with the 1.5 °C and 2 °C temperature targets

Abstract

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.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Global emissions and warming for the ten representative cases.
Fig. 2: Gas-specific abatement and selected Earth system outcomes for the ten representative cases.

References

  1. 1.

    Geden, O. An actionable climate target. Nat. Geosci. 9, 340–342 (2016).

    CAS  Article  Google Scholar 

  2. 2.

    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).

    Article  Google Scholar 

  3. 3.

    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).

    Article  Google Scholar 

  4. 4.

    Rogelj, J. et al. Zero emission targets as long-term global goals for climate protection. Environ. Res. Lett. 10, 105007 (2015).

    Article  Google Scholar 

  5. 5.

    Hallegatte, S. et al. Mapping the climate change challenge. Nat. Clim. Change 6, 663–668 (2016).

    Article  Google Scholar 

  6. 6.

    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).

    Article  Google Scholar 

  7. 7.

    Schleussner, C.-F. et al. Science and policy characteristics of the Paris Agreement temperature goal. Nat. Clim. Change 6, 827–835 (2016).

    Article  Google Scholar 

  8. 8.

    Robiou du Pont, Y. et al. Equitable mitigation to achieve the Paris Agreement goals. Nat. Clim. Change 7, 38–43 (2017).

    Article  Google Scholar 

  9. 9.

    Su, X. et al. Emission pathways to achieve 2.0 and 1.5 °C climate targets. Earth’s Future 5, 592–604 (2017).

    Article  Google Scholar 

  10. 10.

    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).

  11. 11.

    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).

    CAS  Article  Google Scholar 

  12. 12.

    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).

  13. 13.

    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).

    Article  Google Scholar 

  14. 14.

    IPCC Climate Change 2013: The Physical Science Basis (eds Stocker, T. F. et al.) (Cambridge Univ. Press: 2013).

  15. 15.

    Tanaka, K., Peters, G. P. & Fuglestvedt, J. S. Policy update: multicomponent climate policy: why do emission metrics matter? Carbon Manag. 1, 191–197 (2010).

    Article  Google Scholar 

  16. 16.

    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).

    Article  Google Scholar 

  17. 17.

    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).

    CAS  Article  Google Scholar 

  18. 18.

    O’Neill, B. C. Economics, natural science, and the costs of global warming potentials. Climatic Change 58, 251–260 (2003).

    Article  Google Scholar 

  19. 19.

    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).

    Article  Google Scholar 

  20. 20.

    Matthews, H. D. & Caldeira, K. Stabilizing climate requires near-zero emissions. Geophys. Res. Lett. 35, L04705 (2008).

    Article  Google Scholar 

  21. 21.

    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).

    Article  Google Scholar 

  22. 22.

    Pierrehumbert, R. T. Short-lived climate pollution. Annu. Rev. Earth Planet. Sci. 42, 341–379 (2014).

    CAS  Article  Google Scholar 

  23. 23.

    Field, C. B. & Mach, K. J. Rightsizing carbon dioxide removal. Science 356, 706–707 (2017).

    CAS  Article  Google Scholar 

  24. 24.

    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).

    Article  Google Scholar 

  25. 25.

    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).

    CAS  Article  Google Scholar 

  26. 26.

    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).

    Article  Google Scholar 

  27. 27.

    Tanaka, K., Raddatz, T. Correlation between climate sensitivity and aerosol forcing and its implication for the ‘climate trap’. Climatic Change 109, 815–825 (2011).

    CAS  Article  Google Scholar 

  28. 28.

    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).

    Article  Google Scholar 

  29. 29.

    Johansson, D. Temperature stabilization, ocean heat uptake and radiative forcing overshoot profiles. Climatic Change 108, 107–134 (2011).

    Article  Google Scholar 

  30. 30.

    van Vuuren, D. P., Weyant, J. & de la Chesnaye, F. Multi-gas scenarios to stabilize radiative forcing. Energy Econ. 28, 102–120 (2006).

    Article  Google Scholar 

  31. 31.

    Walsh, B. et al. Pathways for balancing CO2 emissions and sinks. Nat. Commun. 8, 14856 (2017).

    CAS  Article  Google Scholar 

Download references

Acknowledgements

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.

Author information

Affiliations

Authors

Contributions

B.C.O. conceived of the research. K.T. led the study. K.T. and B.C.O designed the experiment. K.T. performed the model simulations and generated all the figures and tables. K.T. and B.C.O. analysed the results. K.T. and B.C.O. drafted the manuscript.

Corresponding author

Correspondence to Katsumasa Tanaka.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Tables 1–2, Supplementary Figures 1–17 and Supplementary References

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

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

Download citation

Further reading

Search

Sign up for the Nature Briefing newsletter for a daily update on COVID-19 science.
Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing