Sedimentary response to Paleocene-Eocene Thermal Maximum carbon release: A model-data comparison

Possible sources of carbon that may have caused global warming at the Paleocene-Eocene boundary are constrained using an intermediate complexity Earth-system model configured with early Eocene paleogeography. We find that 6800 Pg C (delta C-13 of -22 parts per thousand) is the smallest pulse modeled here to reasonably reproduce observations of the extent of seafloor CaCO3 dissolution. This pulse could not have been solely the result of methane hydrate destabilization, suggesting that additional sources of CO2 such as volcanic CO2, the oxidation of sedimentary organic carbon, or thermogenic methane must also have contributed. Observed contrasts in dissolution intensity between Atlantic and Pacific sites are reproduced in the model by reducing bioturbation in the Atlantic during the event, simulating a potential consequence of the spread of low-oxygen bottom waters.