Characterizing ice sheets during the Pliocene: evidence from data and models

• Main Authors: Hill, D.J., Haywood, A.M., Hindmarsh, R.C.A., Valdes, P.J.
• Other Authors: Williams, M., Gregory, F.J., Schmidt, D.N.
• Format: Book Part
• Language: English
• Published: Geological Society of London 2007
• Subjects: Earth Sciences; Antarctic; East Antarctic Ice Sheet; Sirius; Antarc*; Antarctica; Ice Sheet
• Online Access: http://nora.nerc.ac.uk/id/eprint/2771/; https://nora.nerc.ac.uk/id/eprint/2771/1/TMS_chapter_Plio_cryosphere.pdf; http://www.geolsoc.org.uk/gsl/publications/bookshop/page3093.html

The Pliocene (c. 5.3 - 1.8 Myr BP) was the last epoch of geological time in which global temperatures were generally higher than modern. It is important if we are to understand the dynamics of warm climates. This is particuarly true of the interaction of climate and cryosphere, where the Pliocene may represent the first epoch in which ice sheets, at least on Antarctica, were a permanent feature. In this paper, we review the available evidence for the state of ice sheets during the Pliocene as well as previous attempts to model them. We then present new models and sensitivity studies of the mid-Pliocene East Antarctic Ice Sheet (EAIS) and consider the implications for the debate on ice-sheet stability during the Pliocene. These new reconstructions suggest that the mid-Pliocene EAIS was significantly smaller than modern, but the modelled average mid-Pliocene climate is not sufficient to cause the widespread deglaciation suggested by Sirius Group diatom evidence.