Peter K. Bijl et al., Science 330 (2010), Transient Middle Eocene atmospheric CO2 and temperature variations

Science (5 November 2010), Vol. 330, No. 6005, pp. 819-821;  DOI: 10.1126/science.1193654

Transient Middle Eocene atmospheric CO₂ and temperature variations

1. Peter K. Bijl¹,*, 
2. Alexander J. P. Houben¹,*, 
3. Stefan Schouten², 
4. Steven M. Bohaty³, 
5. Appy Sluijs¹, 
6. Gert-Jan Reichart⁴, 
7. Jaap S. Sinninghe Damsté²,⁴ and 
8. Henk Brinkhuis¹

+Author Affiliations

1. ¹Biomarine Sciences, Institute of Environmental Biology, Faculty of Science, Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, Netherlands.
2. ²Department of Marine Organic Biogeochemistry, NIOZ Royal Netherlands Institute of Sea Research, Post Office Box 59, 1790 AB Den Burg, Texel, Netherlands.
3. ³School of Ocean and Earth Science, University of Southampton, National Oceanography Centre, European Way, Southampton SO14 3ZH, UK.
4. ⁴Geochemistry, Department of Earth Sciences, Faculty of Geosciences, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, Netherlands.

1. *Correspondence e-mail: p.k.bijl@uu.nl (P.K.B.); a.j.p.houben@uu.nl (A.J.P.H.)

Abstract

The long-term warmth of the Eocene (~56 to 34 million years ago) is commonly associated with elevated partial pressure of atmospheric carbon dioxide (pCO₂). However, a direct relationship between the two has not been established for short-term climate perturbations. We reconstructed changes in both pCO₂ and temperature over an episode of transient global warming called the Middle Eocene Climatic Optimum (MECO; ~40 million years ago). Organic molecular paleothermometry indicates a warming of southwest Pacific sea surface temperatures (SSTs) by 3-6 °C. Reconstructions of pCO₂ indicate a concomitant increase by a factor of 2 to 3. The marked consistency between SST and pCO₂ trends during the MECO suggests that elevated pCO₂ played a major role in global warming during the MECO.

Link:  http://www.sciencemag.org/content/330/6005/819.abstract