Skip to main content

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 22: Climatic forcing

                          Duration: 00:00:46


                          The effect of various factors on the climate are expressed as a forcing value (ie: to what extent they force global warming)

                          The forcing value is measured in Wm-2 (the increase in effective energy caused per square metre).

                          There are many natural forcing factors operating over different time periods, from desertification increasing albedo of a planet to the passage of the solar system through the galaxy (Williams, 1975).

                          Even the movements and placement of continents over time has some forcing activity.

                          However, these natural (also called external, or non-radiative) forcing factors are independent of those which directly affect the energy balance of the Earth-atmosphere (called radiative forcing factors) (Shine et al, 1990).


                          Shine, K., Derwent, R.G., Wuebbles, D.J. & Morcette, J.J., 1990. Radiative forcing of climate. In: Climate Change: The IPCC Scientific Assessment, Intergovernmental Panel on Climate Change (IPCC), Houghton, J.T., Jenkins, G.J. & Ephraums, J.J. (eds.). Cambridge University Press, Cambridge, pp. 41-68.

                          Williams, G.E., 1975. Possible relation between periodic glaciation and the flexure of the Galaxy. Earth Planet. Sci. Lett., 26, pp. 361-369.