Transient Middle Eocene atmospheric CO₂ and temperature variations.
The long-term warmth of the Eocene (~56 to 34 million years ago) is commonly associated with elevated partial pressure of atmospheric carbon dioxide (pCO(2)). However, a direct relationship between the two has not been established for short-term climate perturbations. We reconstructed changes in both pCO(2) 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° to 6°C. Reconstructions of pCO(2) indicate a concomitant increase by a factor of 2 to 3. The marked consistency between SST and pCO(2) trends during the MECO suggests that elevated pCO(2) played a major role in global warming during the MECO.
Biomarine Sciences, Institute of Environmental Biology, Faculty of Science, Laboratory of Palaeobotany and Palynology, Utrecht University, Budapestlaan 4, 3584 CD Utrecht, Netherlands. p.k.bijl@uu.nl
Peter K
PK
Bijl
Alexander J P
AJ
Houben
Stefan
S
Schouten
Steven M
SM
Bohaty
Appy
A
Sluijs
Gert-Jan
GJ
Reichart
Jaap S
JS
Sinninghe Damsté
Henk
H
Brinkhuis