Climatic Change

, Volume 65, Issue 1–2, pp 11–38 | Cite as

Nonlinearities, Feedbacks and Critical Thresholds within the Earth's Climate System

  • José A. Rial
  • Roger A. PielkeSr.
  • Martin Beniston
  • Martin Claussen
  • Josep Canadell
  • Peter Cox
  • Hermann Held
  • Nathalie de Noblet-Ducoudré
  • Ronald Prinn
  • James F. Reynolds
  • José D. Salas


The Earth's climate system is highly nonlinear: inputs and outputs are not proportional, change is often episodic and abrupt, rather than slow and gradual, and multiple equilibria are the norm. While this is widely accepted, there is a relatively poor understanding of the different types of nonlinearities, how they manifest under various conditions, and whether they reflect a climate system driven by astronomical forcings, by internal feedbacks, or by a combination of both. In this paper, after a brief tutorial on the basics of climate nonlinearity, we provide a number of illustrative examples and highlight key mechanisms that give rise to nonlinear behavior, address scale and methodological issues, suggest a robust alternative to prediction that is based on using integrated assessments within the framework of vulnerability studies and, lastly, recommend a number of research priorities and the establishment of education programs in Earth Systems Science. It is imperative that the Earth's climate system research community embraces this nonlinear paradigm if we are to move forward in the assessment of the human influence on climate.


Climate System Methodological Issue Earth System Critical Threshold Nonlinear Behavior 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • José A. Rial
    • 1
  • Roger A. PielkeSr.
    • 2
  • Martin Beniston
    • 3
  • Martin Claussen
    • 4
  • Josep Canadell
    • 5
  • Peter Cox
    • 6
  • Hermann Held
    • 4
  • Nathalie de Noblet-Ducoudré
    • 7
  • Ronald Prinn
    • 8
  • James F. Reynolds
    • 9
  • José D. Salas
    • 10
  1. 1.Wave Propagation Laboratory, Department of Geological Sciences CB#3315University of North CarolinaChapel HillU.S.A.
  2. 2.Atmospheric Science Dept.Colorado State UniversityFort CollinsU.S.A
  3. 3.Dept. of GeosciencesGeography, Univ. of FribourgFribourgSwitzerland
  4. 4.Potsdam Institute for Climate Impact ResearchPotsdamGermany
  5. 5.GCP-IPO, Earth Observation CentreCSIROCanberraAustralia
  6. 6.Met Office Hadley CentreBerkshireU.K
  7. 7.DSM/LSCELaboratoire des Sciences du Climat et de l'Environnement, Unité mixte de Recherche CEA-CNRSGif-sur-YvetteFrance
  8. 8.Dept. of Earth, Atmospheric and Planetary SciencesMassachusetts Institute of TechnologyCambridgeU.S.A
  9. 9.Department of Biology and Nicholas School of the Environmental and Earth Sciences, Phytotron Bldg., Science Dr.Duke UniversityDurhamU.S.A
  10. 10.Dept. of Civil EngineeringColorado State UniversityFort CollinsU.S.A

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