The broader aim of my research is to develop a more reliable, less uncertain atmospheric CO2 proxy that can stretch across the Cenozoic and into the Mesozoic. To achieve this I study the stable carbon isotopic ratio of coccolithophores, single celled phytoplankton, that first evolved in the Triassic. Their enigmatic carbon isotopic signatures are related, in part, to the ambient concentration of CO2. Through combining coccolithophore isotopic flux models with sedimentary data I recreate past CO2 levels and reveal insights to coccolithophore physiology. My current aim is to reconstruct CO2 during the Eocene ‘hothouse’ 55-34 million years ago.
View Selected Publications
Chen, T., Robinson, L. F., Beasley, M. P., Claxton, L. M., Andersen, M. B., Lauren, J., Harpp, K. S. (2016). Ocean mixing and ice-sheet control of seawater 234 U / 238 U during the last deglaciation. Science, 1015, 626-629.
Chen, T., Robinson, L. F., Burke, A., Claxton, L., Hain, M. P., Li, T., Rae, J. W. B., Stewart, J., Knowles, T. D. J., Fornari, D. J., & Harpp, K. S. (2020). Persistently well-ventilated intermediate-depth ocean through the last deglaciation. Nature Geoscience, 13(11), 733–738. https://doi.org/10.1038/s41561-020-0638-6