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.
Millennial-Scale Instability of the Antarctic Ice Sheet During the Last Glaciation
Sharon L. Kanfoush,1*
David A. Hodell,1*
Christopher D. Charles,2
Thomas P. Guilderson,3
P. Graham Mortyn,2
Ulysses S. Ninnemann2
Records of ice-rafted detritus (IRD) concentration in deep-sea
cores from the southeast Atlantic Ocean reveal millennial-scalepulses
of IRD delivery between 20,000 and 74,000 years ago. ProminentIRD
layers correlate across the Polar Frontal Zone, suggestingepisodes of
Antarctic Ice Sheet instability. Carbon isotopes (13C)
of benthic foraminifers, a proxy of deepwater circulation,reveal that
South Atlantic IRD events coincided with strong increasesin North
Atlantic Deep Water (NADW) production and inferred warming(interstadials) in the high-latitude North Atlantic. Sea levelrise or
increased NADW production associated with strong interstadialsmay have
resulted in destabilization of grounded ice shelves andpossible
surging in the Weddell Sea region of West Antarctica.
1 Department of Geological Sciences, University
of Florida, Gainesville, FL 32611, USA.
2 Scripps
Institution of Oceanography, University of California, San Diego, CA
92093, USA.
3 Lawrence Livermore National
Laboratory, Livermore, CA 94550, USA, and Department of Earth and
Planetary Sciences, Harvard University, Cambridge, MA 02138, USA.
*
To whom correspondence should be addressed. E-mail:
skanfou{at}ufl.edu (S.L.K.) and dhodell{at}geology.ufl.edu (D.A.H.)
Present address: Borehole Research Group,
Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY
10964, USA.
The editors suggest the following Related Resources on Science sites:
In Science Magazine
LETTERS
Peter U. Clark, Nicklas G. Pisias;, Sharon L. Kanfoush, David A. Hodell, and Thomas P. Guilderson (6 October 2000) Science290 (5489), 51c.
[DOI: 10.1126/science.290.5489.51c] |Full Text »
THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Glacial-interglacial terrigenous provenance in the southeastern Atlantic Ocean: The importance of deep-water sources and surface currents.
J. C. Latimer, G. M. Filippelli, I. L. Hendy, J. D. Gleason, and J. D. Blum (2006)
Geology
34, 545-548
|Abstract »|Full Text »|PDF »
Ice Sheet and Solid Earth Influences on Far-Field Sea-Level Histories.
S. E. Bassett, G. A. Milne, J. X. Mitrovica, and P. U. Clark (2005)
Science
309, 925-928
|Abstract »|Full Text »|PDF »
Relationship between Antarctic sea ice and southwest African climate during the late Quaternary.
(2004)
Geology
32, 909-912
340,000-Year Centennial-Scale Marine Record of Southern Hemisphere Climatic Oscillation.
K. Pahnke, R. Zahn, H. Elderfield, and M. Schulz (2003)
Science
301, 948-952
|Abstract »|Full Text »|PDF »
Meltwater Pulse 1A from Antarctica as a Trigger of the Bolling-Allerod Warm Interval.
A. J. Weaver, O. A. Saenko, P. U. Clark, and J. X. Mitrovica (2003)
Science
299, 1709-1713
|Abstract »|Full Text »|PDF »
Holocene history of the Wilson Piedmont Glacier along the southern Scott Coast, Antarctica.
B. L. Hall, B. L. Hall, and G. H. Denton (2002)
The Holocene
12, 619-627
|Abstract »|PDF »
New Ages for the Last Australian Megafauna: Continent-Wide Extinction About 46,000 Years Ago.
R. G. Roberts, T. F. Flannery, L. K. Ayliffe, H. Yoshida, J. M. Olley, G. J. Prideaux, G. M. Laslett, A. Baynes, M. A. Smith, R. Jones, et al. (2001)
Science
292, 1888-1892
|Abstract »|Full Text »|PDF »
13C)
of benthic foraminifers, a proxy of deepwater circulation, reveal that
South Atlantic IRD events coincided with strong increases in North
Atlantic Deep Water (NADW) production and inferred warming (interstadials) in the high-latitude North Atlantic. Sea level rise or
increased NADW production associated with strong interstadials may have
resulted in destabilization of grounded ice shelves and possible
surging in the Weddell Sea region of West Antarctica.
