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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 16: Global circulation models

                          Duration: 00:01:07


                          GCMs enable us to get some picture of future climate responses to given situations. As the IPCC puts it, GCMs "...are the only credible tools currently available for simulating the response of the global climate system to increasing greenhouse gas concentrations". The first GCM was developed in the 1950's by Norman Philips. It was an incredibly simple model, comprising just two atmospheric layers, and two hemispheric sectors in which the model functions were run.

                          Other early GCMs involved up to five atmospheric layers, over a simple oceanic model. The model would be set with a given CO2 level, and then allowed to run to equilibrium, at which point the CO2 was raised to a new level (such as 600 ppm), and then run to equilibrium again. Needless to say, such simple models were no more than a sketch of the likely climatic response, and contemporary models are considerably more complex. Furthermore, recent models allow transient, or incremental, increases in gas concentrations to be modelled.

                          They are 3-D, and may comprise thousands of individual cells


                          IPCC-TGCIA (1999): Guidelines on the Use of Scenario Data for Climate Impact and Adaptation Assessment. Version 1. Prepared by Carter, T.R., Hulme, M. and Lal, M., Intergovernmental Panel on Climate Change, Task Group on Scenarios for Climate Impact Assessment, 69 pp.