The problems: One of the most significant events in recent Earth history has been the transition into a "glacial world" and the development of glacial-interglacial variability over the last 3 million years. The marked expansion of ice volume at ~2.5 Ma also signifies a major change in the scale of Earth's climate variability. Numerous explanations have been put forward to account for this change (Bintanja & van de Wal, 2008, and references therein) and much is known about variations in ice sheet size and the impact that this had on deep ocean temperatures and circulation patterns. Comparatively little is known in detail about sea surface temperature (SST) changes at this time as the methods widely used to reconstruct SST variability in the Quaternary cannot be easily applied, because ~40% of all planktonic foraminiferal species found in the North Atlantic during the late Pliocene became extinct (Chapman, 2000). Palaeoceanographic reconstructions of surface heat transport into and out of the northern North Atlantic and the pathways of iceberg discharge events across the ocean have provided valuable insights into the operation of the meridional overturning circulation in the Quaternary. There is considerable evidence to suggest that the surface hydrology was significantly modified through lowered temperature and salinity during these events (Ellison et al., 2006) but further work is required to better constrain the extent of cooling using a suite of methods across the region.

The research: The aim of this project is to perform analyses of deep-sea sediment cores in order to better characterise the nature and extent of ocean cooling in terms of glacial-interglacial climatic variability and millennial-scale events. Work will focus on the onset of major glaciations in the Northern Hemisphere and compare this to recent records from the Quaternary. The proposed research will fill a gap in our knowledge by producing better constrained geochemical-based SST records (stable isotope, Mg/Ca and "clumped isotope" techniques) and will provide an important means of quantifying uncertainty in palaeoclimate reconstructions. This project will provide an exciting opportunity for a student interested in exploring and applying a combination of geochemical and palaeoecological proxies.

Requirements, training and opportunities: We seek an enthusiastic, self-motivated scientist with at least a 2(i) honours degree in Earth Science or Environmental Science, and a strong interest/experience in geochemistry and good numerical ability. The student will join an active climate science community at UEA and be able to attend courses (e.g., palaeoclimatology and oceanography) to study the physical and dynamical processes that control past variability of ocean and climate system and underpin our understanding of Quaternary palaeoclimatology. It is envisaged that the student will have the opportunity to gain seagoing experience and collect new marine sediment core material that could be utilised during the studentship.

Bintanja, R. & van de Wal, R.S.W., 2008: Nature, v. 454, p. 869-872.

Chapman, M.R., 2000, in Culver, S.J. and Rawson, P.F., eds., Biotic Response to Global Change: the last 145 million years, Cambridge University Press, p. 79-96.

Ellison, C. R. W., Chapman, M. R. and Hall, I. R., 2006, Surface and deep ocean interactions during the cold climate event 8,200 years ago, Science, v. 312, p. 1929 – 1932. doi:10.1126/science.1127213