KEYNOTE: SOILS, WATER, AND TERRESTRIAL-MARINE CONNECTIVITY THROUGH THE PALEOCENE-EOCENE THERMAL MAXIMUM

Carbon isotope and paleosol records document the effect of a major carbon cycle perturbation at 55 Ma on terrestrial plant and soil systems. These changes are coupled with a huge fluctuation in the state of the marine carbonate system, as reflected in changing burial rate of carbonate in seafloor sediments. I will first present the evidence for these changes, and then explore the mechanisms by which the oceanic and terrestrial carbon cycles appear to have been coupled during the event. In particular, the hydrologic cycle appears to have been a fundamentally important component of the feedback loop involving the terrestrial and marine carbon cycles, providing strong evidence for the close and dynamic linkage of hydrologic and geochemical systems during rapid climate change.