Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Climate impacts of energy technologies depend on emissions timing

Nature Climate Change volume 4, pages 347–352 (2014)Cite this article

Subjects

An Erratum to this article was published on 28 May 2014

This article has been updated

Abstract

Energy technologies emit greenhouse gases with differing radiative efficiencies and atmospheric lifetimes1,2,3. Standard practice for evaluating technologies, which uses the global warming potential (GWP) to compare the integrated radiative forcing of emitted gases over a fixed time horizon4, does not acknowledge the importance of a changing background climate relative to climate change mitigation targets5,6. Here we demonstrate that the GWP misvalues the impact of CH4-emitting technologies as mid-century approaches, and we propose a new class of metrics to evaluate technologies based on their time of use. The instantaneous climate impact (ICI) compares gases in an expected radiative forcing stabilization year, and the cumulative climate impact (CCI) compares their time-integrated radiative forcing up to a stabilization year. Using these dynamic metrics, we quantify the climate impacts of technologies and show that high-CH4-emitting energy sources become less advantageous over time. The impact of natural gas for transportation, with CH4 leakage, exceeds that of gasoline within 1–2 decades for a commonly cited 3 W m−2 stabilization target. The impact of algae biodiesel overtakes that of corn ethanol within 2–3 decades, where algae co-products are used to produce biogas and corn co-products are used for animal feed. The proposed metrics capture the changing importance of CH4 emissions as a climate threshold is approached, thereby addressing a major shortcoming of the GWP for technology evaluation7,8.

This is a preview of subscription content, access via your institution

Relevant articles

Open Access articles citing this article.

Access options

Rent or buy this article

Get just this article for as long as you need it

$39.95

Learn more

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Comparisons of greenhouse gases and technologies depend on the evaluation horizon.
Figure 2: GWP(100) underestimates the radiative forcing contribution of CH4-emitting technologies.
Figure 3: Metric development.
Figure 4: Technology comparisons.
Figure 5: Simulations of radiative forcing and vehicle kilometres travelled.

Change history

  • 25 April 2014

    In the print version of this Letter, the y axes in Fig. 4a,b should have been labelled 'Impact (g CO2-eq km-1)'. In addition, the first sentence of the author contributions should have read 'J.E.T. developed the concept and designed the methods for the study.' These errors have been corrected in the HTML and PDF versions of the Letter.

References

  1. Alvarez, R. A., Pacala, S. W., Winebrake, J. J., Chameides, W. L. & Hamburg, S. P. Greater focus needed on methane leakage from natural gas infrastructure. Proc. Natl Acad. Sci. USA 109, 6435–6440 (2012).

    Article  CAS  Google Scholar 

  2. Frank, E. D., Han, J., Palou-Rivera, I., Elgowainy, A. & Wang, M. Q. Methane and nitrous oxide emissions affect the life-cycle analysis of algal biofuels. Environ. Res. Lett. 7, 1–10 (2012).

    Google Scholar 

  3. Stratton, R. W., Wolfe, P. J. & Hileman, J. I. Impact of aviation non-CO2 combustion effects on the environmental feasibility of alternative jet fuels. Environ. Sci. Technol. 45, 10736–10743 (2011).

    Article  CAS  Google Scholar 

  4. Solomon, S. et al. Climate Change 2007: The Physical Science Basis (Cambridge Univ. Press, (2007).

    Google Scholar 

  5. Daniel, J. S. et al. Limitations of single-basket trading: Lessons from the Montreal Protocol for climate policy. Climatic Change 111, 241–248 (2011).

    Article  Google Scholar 

  6. Smith, S. M. et al. Equivalence of greenhouse-gas emissions for peak temperature limits. Nature Clim. Change 2, 8–11 (2012).

    Article  Google Scholar 

  7. Azar, C. & Johansson, D. J. A. Valuing the non-CO2 climate impacts of aviation. Climatic Change 111, 559–579 (2011).

    Article  Google Scholar 

  8. Peters, G. P., Aamaas, B., Lund, M. T., Solli, C. & Fuglestvedt, J. S. Alternative ‘global warming’ metrics in life cycle assessment: A case study with existing transportation data. Environ. Sci. Technol. 45, 8633–8641 (2011).

    Article  CAS  Google Scholar 

  9. Kendall, A. Time-adjusted global warming potentials for LCA and carbon footprints. Int. J. Life Cycle Ass. 17, 1042–1049 (2012).

    Article  CAS  Google Scholar 

  10. Shine, K. P. The global warming potential—the need for an interdisciplinary retrial. Climatic Change 96, 467–472 (2009).

    Article  Google Scholar 

  11. Tanaka, K., Johansson, D. J. A., O’Neill, B. C. & Fuglestvedt, J. S. Emissions metrics under a 2 °C stabilization target. Climatic Change 117, 933–941 (2013).

    Article  CAS  Google Scholar 

  12. Fuglestvedt, J. S. et al. Metrics of climate change: Assessing radiative forcing and emission indices. Climatic Change 58, 267–331 (2003).

    Article  Google Scholar 

  13. 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 

  14. Fuglestvedt, J. S. et al. Transport impacts on atmosphere and climate: Metrics. Atmos. Environ. 44, 4648–4677 (2010).

    Article  CAS  Google Scholar 

  15. Shine, K. P., Fuglestvedt, J. S., Hailemariam, K. & Stuber, N. Alternatives to the global warming potential for comparing climate impacts of emissions of greenhouse gases. Climatic Change 68, 281–302 (2005).

    Article  CAS  Google Scholar 

  16. Shine, K. P., Berntsen, T. K., Fuglestvedt, J. S., Skeie, R. B. & Stuber, N. Comparing the climate effect of emissions of short- and long-lived climate agents. Phil. Trans. R. Soc. A 365, 1903–1914 (2007).

    Article  CAS  Google Scholar 

  17. Manne, A. S. & Richels, R. G. An alternative approach to establishing trade-offs among greenhouse gases. Nature 410, 675–677 (2001).

    Article  CAS  Google Scholar 

  18. Johansson, D. J. A. Economics- and physical-based metrics for comparing greenhouse gases. Climatic Change 110, 123–141 (2012).

    Article  CAS  Google Scholar 

  19. Howarth, R. W., Santoro, R. & Ingraffea, A. Methane and the greenhouse-gas footprint of natural gas from shale formations. Climatic Change 106, 679–690 (2011).

    Article  CAS  Google Scholar 

  20. Allen, D. T. et al. Measurements of methane emissions at natural gas production sites in the United States. Proc. Natl Acad. Sci. USA 110 (2013).

  21. Weber, C. L. & Calvin, C. Life cycle carbon footprint of shale gas: Review of evidence and implications. Environ. Sci. Technol. 46, 5688–5695 (2012).

    Article  CAS  Google Scholar 

  22. Burnham, A. et al. Life-cycle greenhouse gas emissions of shale gas, natural gas, coal, and petroleum. Environ. Sci. Technol. 46, 619–627 (2011).

    Article  Google Scholar 

  23. United Nations Framework Convention on Climate Change. Report of the Conference of the Parties on its fifteenth session, held in Copenhagen from 7 to 19 December 2009, FCCC/CP/2009/11/Add.1

  24. Ekholm, T., Lindroos, T. J. & Savolainen, I. Robustness of climate metrics under climate policy ambiguity. Environ. Sci. Policy 31, 44–52 (2013).

    Article  Google Scholar 

  25. Liska, A. J. et al. Improvements in life cycle energy efficiency and greenhouse gas emissions of corn-ethanol. J. Ind. Ecol. 13, 58–74 (2009).

    Article  CAS  Google Scholar 

  26. Scott, S. A. et al. Biodiesel from algae: Challenges and prospects. Curr. Opin. Biotechnol. 21, 277–286 (2010).

    Article  CAS  Google Scholar 

  27. Alley, R. B. et al. Abrupt climate change. Science 299, 2005–2010 (2003).

    Article  CAS  Google Scholar 

  28. Lenton, T. M. Beyond 2 °C: Redefining dangerous climate change for physical systems. WIREs Clim. Change 2, 451–461 (2011).

    Article  Google Scholar 

  29. Lenton, T. M. et al. Tipping elements in the Earth’s climate system. Proc. Natl Acad. Sci. USA 105, 1786–1793 (2008).

    Article  CAS  Google Scholar 

  30. Allen, M. R. et al. Warming caused by cumulative carbon emissions towards the trillionth tonne. Nature 458, 1163–1166 (2009).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

The authors thank J. McNerney for his contributions to the development of the metric testing model. We thank S. Solomon for helpful feedback on this manuscript. This research was partially financially supported by the New England University Transportation Center at MIT under DOT grant No. DTRT07-G-0001.

Author information

Authors and Affiliations

  1. Engineering Systems Division, Massachusetts Institute of Technology, 77 Massachusetts Avenue Cambridge, Massachusetts 02139, USA,

    Morgan R. Edwards & Jessika E. Trancik

  2. Santa Fe Institute, 1399 Hyde Park Road Santa Fe, New Mexico 87501, USA,

    Jessika E. Trancik

Authors
  1. Morgan R. Edwards
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Jessika E. Trancik
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

J.E.T. developed the concept and designed the methods for the study, M.R.E. and J.E.T. performed the analysis, J.E.T. and M.R.E. wrote the paper.

Corresponding author

Correspondence to Jessika E. Trancik.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Rights and permissions

Reprints and Permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Edwards, M., Trancik, J. Climate impacts of energy technologies depend on emissions timing. Nature Clim Change 4, 347–352 (2014). https://doi.org/10.1038/nclimate2204

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nclimate2204

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing