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Atmospheric CO2 forces abrupt vegetation shifts locally, but not globally

Nature volume 488, pages 209212 (09 August 2012) | Download Citation


This article has been updated


It is possible that anthropogenic climate change will drive the Earth system into a qualitatively different state1. Although different types of uncertainty limit our capacity to assess this risk2, Earth system scientists are particularly concerned about tipping elements, large-scale components of the Earth system that can be switched into qualitatively different states by small perturbations. Despite growing evidence that tipping elements exist in the climate system1,3, whether large-scale vegetation systems can tip into alternative states is poorly understood4. Here we show that tropical grassland, savanna and forest ecosystems, areas large enough to have powerful impacts on the Earth system, are likely to shift to alternative states. Specifically, we show that increasing atmospheric CO2 concentration will force transitions to vegetation states characterized by higher biomass and/or woody-plant dominance. The timing of these critical transitions varies as a result of between-site variance in the rate of temperature increase, as well as a dependence on stochastic variation in fire severity and rainfall. We further show that the locations of bistable vegetation zones (zones where alternative vegetation states can exist) will shift as climate changes. We conclude that even though large-scale directional regime shifts in terrestrial ecosystems are likely, asynchrony in the timing of these shifts may serve to dampen, but not nullify, the shock that these changes may represent to the Earth system.

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Change history

  • 08 August 2012

    Axis labelling in Fig. 1d was corrected.


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We thank D. Bennu and T. Hickler for helping us improve the manuscript. Financial support was provided by the Deutsche Forschungsgemeinschaft and Hesse’s Landes-Offensive zur Entwicklung Wissenschaftlich-ökonomischer Exzellenz (LOEWE) programme.

Author information


  1. Institut für Physische Geographie, Goethe Universität Frankfurt am Main, Altenhöferallee 1, 60438 Frankfurt am Main, Germany

    • Steven I. Higgins
  2. Biodiversity and Climate Research Centre (BiK-F), Senckenberg Gesellschaft für Naturforschung, Senckenberganlage 25, 60325 Frankfurt am Main, Germany

    • Simon Scheiter


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S.I.H. and S.S. jointly conceived the study. S.S. ran the simulations. S.I.H. led the writing.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Steven I. Higgins.

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    Supplementary Information

    This file contains Supplementary Methods, Supplementary Tables 1-2 and additional references.

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