Marine palaeoclimatology

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Marine palaeoclimatology

  1. 1. Marine palaeoclimatology<br />Professor Simon K. Haslett<br />Centre for Excellence in Learning and Teaching<br />Simon.haslett@newport.ac.uk<br />27th September 2010<br />
  2. 2. Introduction<br />The study of palaeoclimates enables us:<br />to establish the limits of natural climatic variability;<br />to establish climatic trends;<br />to place present-day climate in context;<br />to provide analogies for future climate and environment predictions; and<br />to provide hindcast tests of predictive climate models.<br />There are two approaches to studying palaeoclimates:<br />palaeoclimaticmodelling: use GCMs to simulate past climates; and<br />palaeogeographic and palaeoecologic reconstruction: use proxy data to reconstruct palaeoclimate.<br />This presentation describes how integrated records of marine and terrestrial environmental change are found in marine sediments.<br />
  3. 3. Marine palaeoclimatology<br />Marine palaeoclimatology attempts to reconstruct palaeoclimates using marine geological phenomena, such as:<br /><ul><li>marine sediments (including sedimentology, micropalaeontology, isotope analysis etc);
  4. 4. coral reefs (skeletal growth variations, isotope analysis etc).</li></ul>Some coastal cores. The benefit of using marine evidence is that they often provide continuous records, whereas land-based records are fragmentary, often interrupted by erosion events (not applicable to ice-core records which are often complete but, with a few exceptions, are latitudinally restricted).<br />
  5. 5. Case study: the CLIMAP Project<br />Stands for Climate: Long-range Investigation Mapping and Prediction.<br />Attempted to reconstruct seasonal changes (February and August) in global geography at the Last Glacial Maximum (LGM) (18+3 ka), by establishing global sea-surface temperatures (SSTs).<br />Took place in the 1970s and 1980s and involved scientists from all over the world.<br />
  6. 6. Case study: the CLIMAP Project<br />Achieved by:<br />analysing modern plankton distribution in surface sediments;<br />analysing fossil plankton in LGM sediments;<br />summarising all plankton data using Factor Analysis;<br />converting fossil plankton data into SSTs based on modern plankton/SST relationships;<br />constructing maps based on these data;<br />comparing LGM and present-day SST.<br />Foraminifera (e), diatoms (8) and dinoflagellates (6) inhabit the water column as plankton.<br />
  7. 7. Case study: the CLIMAP Project<br />CLIMAP (1976) was significant because:<br />It was the first project to provide constraining data for GCMs (Dawson, 1992);<br />It provided testable results which stimulated research into:<br />refinement of existing, and development of new, techniques, including downcore applications.<br />land-based records for land-ocean comparisons (e.g. Rind and Peteet, 1985; Haslett, 2002);<br />Stimulated research into other climatically significant times, such as the mid-Pliocene (PRISM Project e.g.Dowsett, 1994), Plio-Pleistocene Boundary (Olduvai Project e.g.Funnellet al., 1996), last interglacial (Ruddiman, 1984), the Holocene (COHMAP Project, 1988), as well as continued research on the LGM (Wolff et al., 1998; EPILOG Project, Mix et al., 2001). <br />However, some of this further work has cast doubt over the CLIMAP Project results (e.g. Rind and Peteet, 1985), which has led to some controversy in the palaeoclimate community (Haslett, 2002).<br />
  8. 8. Marine palaeoclimatology practical<br />This practical is designed to introduce you to planktonic foraminifera, an important marine palaeoclimatic tool, as used by <br />the CLIMAP Project.<br />This should be done by familiarising yourself with the following common species, using the informationprovided in this <br />presentation and pictures in Haslett and Kersley (1995) and Haslett (2002). You need to make notes about <br />distinguishing characteristics which help to identify the species (use drawings where appropriate) and also their <br />ecological/sea-surface temperature preferences.<br /><ul><li>Globigerinoidesconglobatus
  9. 9. Globigerinoidesruber
  10. 10. Globigerinoidessacculifer
  11. 11. Globorotaliamenardii/tumida
  12. 12. Neogloboquadrinadutertrei
  13. 13. Orbulinauniversa
  14. 14. Pulleniatinaobliquiloculata
  15. 15. Sphaeroidinelladehiscens
  16. 16. Have a look through some of the rarer species too.</li></ul>Orbulinauniversa(left), Globorotaliatumida(right)<br />
  17. 17. Summary<br />Marine palaeoclimatologyis the study of climate change using marine sediments.<br />The CLIMAP Project reconstructed the earth’s climate for the Last Glacial Maximum.<br />This was achieved by examining proxy data from ocean sediment cores.<br />It provided valuable results which are still used today (albeit controversially), and stimulated research into other palaeoclimate areas.<br />
  18. 18. References<br />CLIMAP Project Members. 1976. The surface of ice age earth. Science, 191: 1131-1137.<br />COHMAP. 1988. Climatic changes of the last 18,000 years: observations and model simulations. Science, 241: 1043-1051.<br />Dawson, A.G. 1992. Ice age earth: late quaternary geology and climate. Routledge, New York.<br />Dowsett, H.J., Thompson, R., Barron, J., Cronin, T., Fleming, F., Ishman, S., Poore, R., Willard, D. and Holtz Jr., T. 1994. Joint investigations of the Middle Pliocene climate 1: PRISM palaeoenvironmental reconstructions. Global and Planetary Change, 9: 169-195.<br />Funnell, B.M., Haslett, S.K., Kennington, K., Swallow, J.E. and Kersley, C.L. 1996. Strangeness of the equatorial ocean during the Olduvai magnetosubchron (1.95 to 1.79 Ma). In: Moguilevsky, A. and Whatley, R. (eds.). Microfossils and Oceanic Environments. University of Wales, Aberystwyth Press, pp. 93-109.<br />Haslett, S.K. 2002. Palaeoceanographic applications of planktonic Sarcodine Protozoa: Radiolaria and Foraminifera. pp. 139-165. In: Haslett, S.K. (ed.). Quaternary Environmental Micropalaeontology. Arnold, London, 340pp.<br />Haslett, S.K. and Kersley, C.L. 1995. Early Pleistocene planktonic foraminifera from the tropical Indian Ocean. Microscopy and Analysis, March, 25-27.<br />Mix, A.C., Bard, E. and Schneider, R. 2001. Environmental processes of the ice age: land, oceans, glaciers (EPILOG). Quaternary Science Reviews, 20: 627-657.<br />Rind, D. and Peteet, D. 1985. Terrestrial conditions at the Last Glacial Maximum and CLIMAP sea-surface temperature estimates – are they consistent? Quaternary Research, 24: 1-22.<br />Ruddiman, W.F. 1984. The last interglacial ocean. CLIMAP Project Members. Quaternary Research, 21: 123-224.<br />Wolff, T., Mulitza, S., Arz, H., Patzold, J. and Wefer, G. 1998. Oxygen isotopes versus CLIMAP (18 ka) temperatures: a comparison from the tropical Atlantic. Geology, 26: 675-678.<br />
  19. 19. This resource was created by the University of Wales, Newport and released as an open educational resource through the 'C-change in GEES' project exploring the open licensing of climate change and sustainability resources in the Geography, Earth and Environmental Sciences. The C-change in GEES project was funded by HEFCE as part of the JISC/HE Academy UKOER programme and coordinated by the GEES Subject Centre. <br /> This resource is licensed under the terms of the Attribution-Non-Commercial-Share Alike 2.0 UK: England & Wales license (http://creativecommons.org/licenses/by-nc-sa/2.0/uk/). <br /> All images courtesy of Professor Simon Haslett. However the resource, where specified below, contains other 3rd party materials under their own licenses. The licenses and attributions are outlined below:<br />The name of the University of Wales, Newport and its logos are unregistered trade marks of the University. The University reserves all rights to these items beyond their inclusion in these CC resources. <br />The JISC logo, the C-change logo and the logo of the Higher Education Academy Subject Centre for the Geography, Earth and Environmental Sciences are licensed under the terms of the Creative Commons Attribution -non-commercial-No Derivative Works 2.0 UK England & Wales license. All reproductions must comply with the terms of that license.<br />

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