Abstract

A series of transient global warming events occurred during the late Paleocene and Early Eocene (~59-50 Ma ago), of varying magnitude but apparently paced by orbital cycles. Here we present a hierarchy of climate models of varying complexity, that (1) provide a link between orbital variations and warming due to the destabilisation of hydrates stored in marine sediments through changes in global ocean circulation, and (2) account for the decreasing magnitude and increasing frequency of the hyperthermal events through the Early Eocene. However, how robust are these model results, and really how well do they agree with the palaeo record?

References: Lunt, D.J., Ridgwell, A., Sluijs, A., Zachos, J., Hunter, S. Haywood, A. (2011). A model for orbital pacing of methane hydrate destabilization during the Palaeogene, Nature Geoscience, 4, 775-778. [doi:10.1038/ngeo1266].

Lunt, D.J., Valdes, P.J. Valdes, Dunkley Jones, T, Ridgwell, A., Haywood, A.M., Schmidt, D.N., Marsh, R., Maslin, M. (2010). CO2 -driven ocean circulation changes as an amplifier of Paleocene-Eocene thermal maximum hydrate destabilization. Geology, 38, 875-878. [doi:10.1130/G31184.1].