Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.
AAAS Promotion

Site Tools

  • AAAS
  • Subscribe
  • Feedback

Site Search

Search Advanced

Originally published in Science Express on 16 June 2005
Science 22 July 2005:
Vol. 309. no. 5734, pp. 600 - 603
DOI: 10.1126/science.1110063

Reports

Marked Decline in Atmospheric Carbon Dioxide Concentrations During the Paleogene

Mark Pagani,1 James C. Zachos,2 Katherine H. Freeman,3 Brett Tipple,1 Stephen Bohaty2

The relation between the partial pressure of atmospheric carbon dioxide (pCO2) and Paleogene climate is poorly resolved. We used stable carbon isotopic values of di-unsaturated alkenones extracted from deep sea cores to reconstruct pCO2 fromthe middle Eocene to the late Oligocene (~45 to 25 million years ago). Our results demonstrate that pCO2 ranged between 1000 to 1500 parts per million by volume in the middle to late Eocene, then decreased in several steps during the Oligocene, and reached modern levels by the latest Oligocene. The fall in pCO2 likely allowed for a critical expansion of ice sheets on Antarctica and promoted conditions that forced the onset of terrestrial C4 photosynthesis.

1 Department of Geology and Geophysics, Yale University, 210 Whitney Avenue, New Haven, CT 06511, USA.
2 Earth Sciences Department, University of California, 1156 High Street, Santa Cruz, CA 95064, USA.
3 Department of Geosciences, Pennsylvania State University, University Park, PA 16802, USA.

Published online 16 June 2005

Include this information when citing this paper.

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Evolution of Mammals and Their Gut Microbes.
R. E. Ley, M. Hamady, C. Lozupone, P. J. Turnbaugh, R. R. Ramey, J. S. Bircher, M. L. Schlegel, T. A. Tucker, M. D. Schrenzel, R. Knight, et al. (2008)
Science 320, 1647-1651
   Abstract »    Full Text »    PDF »
A snowball Earth versus a slushball Earth: Results from Neoproterozoic climate modeling sensitivity experiments.
A. Micheels and M. Montenari (2008)
Geosphere 4, 401-410
   Abstract »    Full Text »    PDF »
Cooling and ice growth across the Eocene-Oligocene transition.
C. H. Lear, T. R. Bailey, P. N. Pearson, H. K. Coxall, and Y. Rosenthal (2008)
Geology 36, 251-254
   Abstract »    Full Text »    PDF »
Onset of long-term cooling of Greenland near the Eocene-Oligocene boundary as revealed by branched tetraether lipids.
S. Schouten, J. Eldrett, D. R. Greenwood, I. Harding, M. Baas, and J. S. S. Damste (2008)
Geology 36, 147-150
   Abstract »    Full Text »    PDF »
Descent into the Icehouse.
E. Thomas (2008)
Geology 36, 191-192
   Full Text »    PDF »
From the Cover: The impact of Miocene atmospheric carbon dioxide fluctuations on climate and the evolution of terrestrial ecosystems.
W. M. Kurschner, Z. Kvacek, and D. L. Dilcher (2008)
PNAS 105, 449-453
   Abstract »    Full Text »    PDF »
Linkages between CO2, climate, and evolution in deep time.
D. L. Royer (2008)
PNAS 105, 407-408
   Full Text »    PDF »
Paleoelevation Reconstruction using Pedogenic Carbonates.
J. Quade, C. Garzione, and J. Eiler (2007)
Reviews in Mineralogy and Geochemistry 66, 53-87
   Full Text »    PDF »
Late Oligocene initiation of the Antarctic Circumpolar Current: Evidence from the South Pacific.
M. Lyle, S. Gibbs, T. C. Moore, and D. K. Rea (2007)
Geology 35, 691-694
   Abstract »    Full Text »    PDF »
Stable warm tropical climate through the Eocene Epoch.
P. N. Pearson, B. E. van Dongen, C. J. Nicholas, R. D. Pancost, S. Schouten, J. M. Singano, and B. S. Wade (2007)
Geology 35, 211-214
   Abstract »    Full Text »    PDF »
CO2-Forced Climate and Vegetation Instability During Late Paleozoic Deglaciation.
I. P. Montanez, N. J. Tabor, D. Niemeier, W. A. DiMichele, T. D. Frank, C. R. Fielding, J. L. Isbell, L. P. Birgenheier, and M. C. Rygel (2007)
Science 315, 87-91
   Abstract »    Full Text »    PDF »
The enigma of early Miocene biserial planktic foraminifera.
C. W. Smart and E. Thomas (2006)
Geology 34, 1041-1044
   Abstract »    Full Text »    PDF »
Benthic foraminiferal Li/Ca: Insights into Cenozoic seawater carbonate saturation state.
C. H. Lear and Y. Rosenthal (2006)
Geology 34, 985-988
   Abstract »    Full Text »    PDF »
Elevated Eocene atmospheric CO2 and its subsequent decline..
T. K. Lowenstein and R. V. Demicco (2006)
Science 313, 1928
   Abstract »    Full Text »    PDF »
Scleractinian corals produce calcite, and grow more slowly, in artificial Cretaceous seawater.
J. B. Ries, S. M. Stanley, and L. A. Hardie (2006)
Geology 34, 525-528
   Abstract »    Full Text »    PDF »
Cenozoic plant diversity in the neotropics..
C. Jaramillo, M. J. Rueda, and G. Mora (2006)
Science 311, 1893-1896
   Abstract »    Full Text »    PDF »
Ice-Sheet and Sea-Level Changes.
R. B. Alley, P. U. Clark, P. Huybrechts, and I. Joughin (2005)
Science 310, 456-460
   Abstract »    Full Text »    PDF »



ADVERTISEMENT
Click Me!

ADVERTISEMENT
Click Me!

To Advertise     Find Products


Science. ISSN 0036-8075 (print), 1095-9203 (online)