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Table of Contents

  1. Introduction: AIACC: Climate Change and Conservation Planning
    1. Chapter1: Evidence for climate change
      1. Chapter 2: Global circulation models
        1. Slide 1: Global Circulation Models - the basis for climate change science
        2. Slide 2: Weather prediction
        3. Slide 3: NWP vs climate models
        4. Slide 4: NWP vs climate models (cont)
        5. Slide 5: How does the climate work?
        6. Slide 6: The atmosphere I: vertical structure
        7. Slide 7: The atmosphere II: energy budget
        8. Slide 8: The atmosphere III: Horizontal transfers
        9. Slide 9: The oceans
        10. Slide 10: Biosphere
        11. Slide 11: The geosphere
        12. Slide 12 : Different types of climate models
        13. Slide 13: Energy balance models
        14. Slide 14: Radiative-convective models
        15. Slide 15: Statistical-dynamical models
        16. Slide 16: Global circulation models
        17. Slide 17: Contemporary GCMs: an outline
        18. Slide 18: Climatic processes modelled in a GCM
        19. Slide 19: Flux adjustments
        20. Slide 20: How many GCMs are there?
        21. Slide 21: Use of GCMs
        22. Slide 22: Climatic forcing
        23. Slide 23: The effects of current radiative forcings
        24. Slide 24: IPCC future scenarios
        25. Slide 25: Development scenarios (cont).
        26. Slide 26: Future radiative forcings depend on response
        27. Slide 27: GCM model responses
        28. Slide 28: GCM outputs for 2100 (I)
        29. Slide 29: GCM outputs for 2100 (II)
        30. Slide 30: Linear and non linear responses
        31. Slide 31: Examples of non-linear changes
        32. Slide 32: Conclusion
        33. Slide 33: Test yourself
        34. Slide 34 Links to other chapters
      2. Chapter 4: Biodiversity responses to past changes in climate
        1. Chapter 5: Adaptation of biodiversity to climate change
          1. Chapter 6: Approaches to niche-based modelling
            1. Chapter 7: Ecosystem function modelling
              1. Chapter 8: Climate change implications for conservation planning
                1. Chapter 9: The economic costs of conservation response options for climate change
                  1. Course Resources
                    1. Practical: Conservation for Climate Change
                      1. Tests to Assess your Understanding
                        1. How to run a GAM model in R

                          Slide 31: Examples of non-linear changes

                          Duration: 00:01:22


                          Most GCMs show a slowing of the Atlantic Thermohaline Circulation as the world heats up. However, some show the circulation stopping entirely as heating reaches a threshold value. (Manabe and Stouffer, 1988). The shutdown does not occur abruptly, but the speed with which it stops (decades to centuries) is affected by the rate of heating.

                          Sea ice in the northern seas is set to reduce, and this process may be accelerated by feedback processes associated with the concurrent drop in salinity and reduced albedo.

                          Sea level rise may destabilise large polar ice masses, ice sheets, or even entire ice shelves, accelerating sea level rise.

                          Observed variability of ENSO indicate a transition to increased occurrence of ENSO in 1976, although not enough is know to say whether this is an anthropogenic effect, or even if it is a long-term transition.

                          Large-scale (possibly irreversible) transformations in the biosphere such as the growth of the Sahara desert (Claussen et al., 1999), have occurred even with minimal anthropogenic interaction. These can be seen as non-linear changes triggered by slow changes in forcing factors, and it seems highly possible that this could occur given the current level of anthropogenic disturbance. However, not enough is know about this incredibly complex system to say this with any degree of certainty.


                          Claussen, M., C. Kubatzki, V. Brovkin, A. Ganopolski, P. Hoelzmann and H.-J. Pachur, 1999: Simulation of an abrupt change in Saharan vegetation in the mid-Holocene. Geophys. Res. Lett., 26, 2037-2040.

                          Manabe, S. and R.J. Stouffer, 1988: Two stable equilibria of a coupled ocean atmosphere model. J. Clim., 1, 841-866