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.


Science 13 March 2009:
Vol. 323. no. 5920, pp. 1443 - 1448
DOI: 10.1126/science.1167441

Research Articles

Wind-Driven Upwelling in the Southern Ocean and the Deglacial Rise in Atmospheric CO2

R. F. Anderson,1,2* S. Ali,1,2 L. I. Bradtmiller,1,2{dagger} S. H. H. Nielsen,3 M. Q. Fleisher,1 B. E. Anderson,1 L. H. Burckle1

Wind-driven upwelling in the ocean around Antarctica helps regulate the exchange of carbon dioxide (CO2) between the deep sea and the atmosphere, as well as the supply of dissolved silicon to the euphotic zone of the Southern Ocean. Diatom productivity south of the Antarctic Polar Front and the subsequent burial of biogenic opal in underlying sediments are limited by this silicon supply. We show that opal burial rates, and thus upwelling, were enhanced during the termination of the last ice age in each sector of the Southern Ocean. In the record with the greatest temporal resolution, we find evidence for two intervals of enhanced upwelling concurrent with the two intervals of rising atmospheric CO2 during deglaciation. These results directly link increased ventilation of deep water to the deglacial rise in atmospheric CO2.

1 Lamont-Doherty Earth Observatory of Columbia University, Post Office Box 1000, Palisades, NY 10964, USA.
2 Department of Earth and Environmental Sciences, Columbia University, New York, NY 10027, USA.
3 Antarctic Marine Geological Research Facility, Florida State University, Tallahassee, FL 32306, USA.

{dagger} Present address: Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.

* To whom correspondence should be addressed. E-mail: boba{at}ldeo.columbia.edu

Read the Full Text



THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Ice Age Terminations.
H. Cheng, R. L. Edwards, W. S. Broecker, G. H. Denton, X. Kong, Y. Wang, R. Zhang, and X. Wang (2009)
Science 326, 248-252
   Abstract »    Full Text »    PDF »



To Advertise     Find Products


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