Mr James A Kershaw

Past changes in earth's climatic state act as "natural experiments", the study of which can aid our understanding of earth system processes and act to constrain models which are used to predict the future evolution of earth's climate. Understanding of how the oceans changed during these periods is of particular importance, since the global oceans play a crucial role in the storage and distribution of heat, carbon and nutrients around the planet.

The chemistry of deep sea corals has been shown to vary with various oceanographic parameters (e.g. temperature, salinity, DIC content), motivating their use as a proxy for past ocean conditions. Crucially, it has been possible to accurately date deep sea coral skeletons using radiometric methods. Such tight age control cannot be achieved with traditional sedimentary and core-based proxies, making corals a valuable archive of rapid climatic events. 

I am focusing on stylasterid corals, an abundant but understudied group of hydrozoan corals. Using a suite of geochemical measurements including stable isotope ratios (ẟ¹¹B, ẟ¹³C, ẟ¹⁸O), metal/Ca ratios, radiometric isotopes and mineraological studies, I study the biocalcification mechanisms of these corals, their resilience to ocean acidification and their use as proxies of past oceanic conditions.