Abstract
Climate change in the 21st Century is becoming a growing concern with a greater necessity for understanding the impacts of anthropogenic induced global warming in the latter part of this century being paramount. An understanding of former periods of global warming in our past may hold the key to explaining the effects in our future.The Pliocene Epoch is the most recent geological period where warmer climates than modern were experienced. In particular, the mid-Pliocene warm period c. 3.3-3.0ma experienced between 2.7-4.0˚C warming which is similar to those predicted by the B1 IPCC projections for the late 21st Century of 1.1-2.9˚C. PRISM currently uses this time slice as part of its PRISM4 reconstruction to create a global-scale model of the Pliocene, which can be used to compare differences in Earth systems. Smaller scale climatic reconstructions, however, offer the basis for comparison with models for the Pliocene.
Sampling of sediments from the Coralline Crag Formation, United Kingdom allowed for the retrieval of benthic ostracod specimens which provided seasonal bottom water temperatures of the Pliocene. Developing upon the prior work of Wilkinson (1980) and Wood et al. (1993), it has been possible to develop temperature reconstructions for the Coralline Crag Formation utilising the mutual climatic range method for the first time. Statistical analyses using binary similarity coefficients and hierarchical clustering, further supplemented the findings to identify temperature changes between the Ramsholt and Sudbourne members of the Coralline Crag Formation. These were then compared against the temperatures produced from the PRISM3D reconstructions to determine the validity of the ranges produced from this work.
The findings determine an average bottom water temperature of 16.5˚C ± 1°C for the Coralline Crag Formation with a winter range of 12-13˚C ± 1°C and summer range of 19-21˚C ± 1°C. When compared to the temperature produced by PRISM3D of 13.21˚C ± 1°C it is suggested the environment of deposition for the Coralline Crag Formation was much warmer than the mPWP. The results produced by this work provide an indication as to the temperatures experienced prior to the mPWP, which may aid in improving future PRISM models, providing a regional reconstruction.
| Date of Award | 2017 |
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| Original language | English |
| Awarding Institution |
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| Supervisor | Adrian Wood (Supervisor) & Jason Jordan (Supervisor) |