XVI International Botanical Congess

Contrasting changes in the global environment at the Cretaceous-Tertiary (65 Ma) boundary and the Paleocene-Eocene (55 Ma) boundary potentially influenced land carbon storage and hence biosphere-atmosphere-climate feedbacks. These responses are however difficult to quantify from the geological record alone, necessitating a global modelling approach. Here, a process-based terrestrial carbon cycle model has been forced with general circulation model paleoclimate simulations of the pre-boundary conditions to establish 'base-case' terrestrial carbon storage figures for investigating the possible responses to global cimate change at 65 and 55 Ma. The imposition of a range of post-boundary changes in climate then permits the derivation of new model solutions. The results will be discussed in the context of land biosphere feedbacks on the atmospheric carbon reservoir.