Methane and environmental change during the Paleocene-Eocene thermal maximum (PETM): Modeling the PETM onset as a two-stage event
Article first published online: 1 MAR 2011
Copyright 2011 by the American Geophysical Union.
Geophysical Research Letters
Volume 38, Issue 5, March 2011
How to Cite
2011), Methane and environmental change during the Paleocene-Eocene thermal maximum (PETM): Modeling the PETM onset as a two-stage event, Geophys. Res. Lett., 38, L05702, doi:10.1029/2010GL046038., , and (
- Issue published online: 1 MAR 2011
- Article first published online: 1 MAR 2011
- Manuscript Accepted: 26 JAN 2011
- Manuscript Revised: 17 JAN 2011
- Manuscript Received: 1 NOV 2010
- carbon cycle dynamics;
- methane emission;
- hyperthermal climate event
 An atmospheric CH4 box model coupled to a global carbon cycle box model is used to constrain the carbon emission associated with the PETM and assess the role of CH4 during this event. A range of atmospheric and oceanic emission scenarios representing different amounts, rates, and isotopic signatures of emitted carbon are used to model the PETM onset. The first 3 kyr of the onset, a pre-isotope excursion stage, is simulated by the atmospheric release of 900 to 1100 Pg C CH4 with a δ13C of −22 to −30‰. For a global average warming of 3°C, a release of CO2 to the ocean and CH4 to the atmosphere totalling 900 to 1400 Pg C, with a δ13C of −50 to −60‰, simulates the subsequent 1-kyr isotope excursion stage. To explain the observations, the carbon must have been released over at most 500 years. The first stage results cannot be associated with any known PETM hypothesis. However, the second stage results are consistent with a methane hydrate source. More than a single source of carbon is required to explain the PETM onset.