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Using ecosystem experiments to improve vegetation models

Nature Climate Change volume 5, pages 528–534 (2015)Cite this article

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Abstract

Ecosystem responses to rising CO2 concentrations are a major source of uncertainty in climate change projections. Data from ecosystem-scale Free-Air CO2 Enrichment (FACE) experiments provide a unique opportunity to reduce this uncertainty. The recent FACE Model–Data Synthesis project aimed to use the information gathered in two forest FACE experiments to assess and improve land ecosystem models. A new 'assumption-centred' model intercomparison approach was used, in which participating models were evaluated against experimental data based on the ways in which they represent key ecological processes. By identifying and evaluating the main assumptions causing differences among models, the assumption-centred approach produced a clear roadmap for reducing model uncertainty. Here, we explain this approach and summarize the resulting research agenda. We encourage the application of this approach in other model intercomparison projects to fundamentally improve predictive understanding of the Earth system.

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Figure 1: Aerial views of FACE experiments.

© CURTIS BOLES, ORNL © WILL OWENS, DUKE UNIVERSITY

Figure 2: Comparison of the benchmarking and model–data synthesis approaches to model intercomparison.
Figure 3: Visual summary of findings of FACE-MDS project.

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Acknowledgements

The ORNL and Duke FACE sites and synthesis activities were supported by the US Department of Energy Office of Science, Biological and Environmental Research programme. This work was initiated under the Benchmarking Ecosystem Response Models with Experimental Data from Long-Term CO2 Enrichment Experiments Working Group supported by the National Center for Ecological Analysis and Synthesis, a centre financially supported by the National Science Foundation (grant EF-0553768), the University of California, Santa Barbara, and the state of California. M.D.K. was also supported by ARC discovery grant DP1094791. S.Z. was also supported by the European Community's Seventh Framework Programme FP7 people programme through grants PERG02-GA-2007-224775 and 238366. T.H. was also supported through the LOEWE initiative for scientific and economic excellence of the German federal state of Hesse. This work is a contribution to the AXA Chair Programme in Biosphere and Climate Impacts and the Grand Challenges in Ecosystems and the Environment initiative at Imperial College. A.K.J. was also supported by the NSF (NSF AGS 12-43071), the US Department of Energy (DOE DE-SC0006706) and NASA LCLUC programme (NASA NNX14AD94G).

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Authors and Affiliations

  1. Department of Biological Science, Macquarie University, 2109, New South Wales, Australia

    Belinda E. Medlyn, Martin G. De Kauwe & I. Colin Prentice

  2. University of Western Sydney, Hawkesbury Institute for the Environment, Locked Bag 1797, Penrith, 2751, New South Wales, Australia

    Belinda E. Medlyn

  3. Biogeochemical Integration Department, Max Planck Institute for Biogeochemistry, Hans-Knöll-Str. 10, Jena, D-07745, Germany

    Sönke Zaehle

  4. Environmental Sciences Division and Climate Change Science Institute, Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, Tennessee, USA

    Anthony P. Walker, Paul J. Hanson, Peter E. Thornton, Colleen M. Iversen, Jeffrey M. Warren & Richard J. Norby

  5. Department of Earth and Environment, Boston University, Boston, 02215, Massachusetts, USA

    Michael C. Dietze

  6. Biodiversity and Climate Research Centre (BiK-F) & Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325, Frankfurt/Main, Germany

    Thomas Hickler

  7. Department of Physical Geography, Goethe University, Altenhöferallee 1, Frankfurt am Main, 60438, Germany

    Thomas Hickler

  8. University of Illinois, Urbana, 61801, Illinois, USA

    Atul K. Jain

  9. Department of Microbiology & Plant Biology, University of Oklahoma, Norman, 73019, Oklahoma, USA

    Yiqi Luo & Heather R. McCarthy

  10. Natural Resource Ecology Laboratory, Colorado State University, Fort Collins, 80523, Colorado, USA

    William Parton

  11. Department of Life Sciences, AXA Chair of Biosphere and Climate Impacts, Grand Challenges in Ecosystems and the Environment and Grantham Institute – Climate Change and the Environment, Silwood Park Campus, Buckhurst Road, SL5 7PY, Ascot, UK

    I. Colin Prentice

  12. Natural Resources Canada, Ottawa, K1A 0Y7, Ontario, Canada

    Shusen Wang

  13. CSIRO Ocean and Atmosphere Flagship, Private Bag 1, Aspendale, 3195, Victoria, Australia

    Ying-Ping Wang

  14. Department of Ecology and Evolutionary Biology, Princeton University, Princeton, 08544, New Jersey, USA

    Ensheng Weng

  15. Division of Environmental Science & Policy, Nicholas School of the Environment, Duke University, Durham, 27708, North Carolina, USA

    Ram Oren

  16. Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), SE-901 83, Umeå, Sweden

    Ram Oren

Authors
  1. Belinda E. Medlyn
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  2. Sönke Zaehle
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  18. Jeffrey M. Warren
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  19. Ram Oren
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  20. Richard J. Norby
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Correspondence to Belinda E. Medlyn.

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Medlyn, B., Zaehle, S., De Kauwe, M. et al. Using ecosystem experiments to improve vegetation models. Nature Clim Change 5, 528–534 (2015). https://doi.org/10.1038/nclimate2621

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