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Table of Contents

  1. Introduction: AIACC: Climate Change and Conservation Planning
    1. Chapter1: Evidence for climate change
      1. Slide 1: Introduction: the evidence for anthropogenic climate change
      2. Slide 2: Climate variation
      3. Slide 3 : Climate change
      4. Slide 4: What are we looking for?
      5. Slide 5: Sources of data - instrumental
      6. Slide 6: Temperature
      7. Slide 7: Palaeoclimate reconstruction from proxy data
      8. Slide 8: Palaeoclimatological time scale
      9. Slide 9: Proxy data sources: Ice cores
      10. Slide 10: Proxy data sources: Dendroclimatology
      11. Slide 11: Proxy data sources: Oceanic sediments
      12. Slide 12: Proxy data sources: Other
      13. Slide 13: The role of climate models
      14. Slide 14: Evidence for change
      15. Slide 15: Thermal indicators: Glacial melting
      16. Slide 16: Thermal indicators: Sea ice
      17. Slide 17: Thermal indicators: permafrost
      18. Slide 18: Thermal indicators: Sea level change
      19. Slide 19: Thermal indicators: Sea temperatures
      20. Slide 20: Is oceanic circulation changing?
      21. Slide 21: The greenhouse effect
      22. Slide 22: Climate change forcings
      23. Slide 23: Greenhouse gases: methane
      24. Slide 24: Greenhouse gases: nitrous oxide
      25. Slide 25: Greenhouse gases: carbon dioxide
      26. Slide 26: Greenhouse gases: others
      27. Slide 27: Aerosols
      28. Slide 28: Sulphates and nitrates
      29. Slide 29:Thermal indicators: global air temperature
      30. Slide 30: Changes in precipitation
      31. Slide 31: Climate change indicators: extreme weather
      32. Slide 32: Conclusions?
      33. Slide 33:Test yourself
      34. Slide 34: Links to other chapters
    2. Chapter 2: Global circulation models
      1. 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 9: Proxy data sources: Ice cores

                          Duration: 00:00:55

                          Notes:

                          Data from ice cores is extracted in a number of ways.

                          Oxygen isotopic analysis (carried out with a mass spectrograph) gives an idea of the temperature at which the ice was deposited (since O18 has a higher vapour pressure, it is preferentially deposited). Thus, as water vapour travels to the poles, O18H2 will be deposited as water ice, and the polar fraction has a lower percentage of O18. In warmer conditions, more O18 will be found in the polar ice (Craig, 1961 ; Morgan, 1982).

                          Atmospheric gas concentrations can be extracted from bubbles formed by the closing off of air pores as firn turns to ice. (Raynaud & Lorius, 1973).

                          Physical variations in ice structure such as crystal size, incidence of melts and number/structure of bubbles give an idea of temperature and frequency of melt periods or deposition (Langway, 1970; Koerner, 1977)

                          REFERENCES:

                          Craig, H., 1961. Standard for reporting concentrations of deuterium and oxygen-18 in natural waters. Science, 133, pp. 1833-1834.

                          Koerner, R.M., 1977. Distribution of microparticles in a 299m core through the Devon Island ice cap, North West Territories, Canada. In: Symposium on Isotopes and Impurities in Snow and Ice, International Association of Scientifc Hydrology Publication No. 118. IASH, Washington D.C., pp. 371-376.

                          Langway, C.C., Jr., 1970. Stratigraphic analysis of a deep ice core from Greenland, Geological Society of America Special Paper 125. Geological Society of America, Boulder, Colorado.

                          Morgan, V.I., 1982. Antarctic Ice Sheet surface oxygen isotope values. J. Glaciol., 28, pp. 315-323.

                          Raynaud, D. & Lorius, C., 1973. Climatic implications of total gas content in ice at Camp Century. Nature, 243, pp. 283-284.