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.

Published Online March 1, 2007
Science DOI: 10.1126/science.1138396

Reports

Submitted on December 4, 2006
Accepted on February 21, 2007

Effect of Sedimentation on Ice-Sheet Grounding-Line Stability

Richard B. Alley 1*, Sridhar Anandakrishnan 1, Todd K. Dupont 2, Byron R. Parizek 3, David Pollard 1

1 Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA.
2 Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA; Department of Earth and Environmental Sciences, University of Illinois at Chicago, Chicago, IL 60607, USA.
3 Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA; Department of Physics, The College of New Jersey, Ewing, NJ 08628, USA.

* To whom correspondence should be addressed.
Richard B. Alley , E-mail: rba6{at}psu.edu

Sedimentation filling space beneath ice shelves helps stabilize ice sheets against retreat in response to rise in relative sea level of at least several meters. Recent Antarctic changes thus cannot be attributed to sea-level rise, strengthening prior interpretations that warming has driven ice-sheet mass loss. Large sea level rise, such as the {approx}100 m at the end of the last ice age, may overwhelm the stabilizing feedback from sedimentation, but smaller sea-level changes are unlikely to have synchronized behavior of ice sheets in the past.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Imprecise probability assessment of tipping points in the climate system.
E. Kriegler, J. W. Hall, H. Held, R. Dawson, and H. J. Schellnhuber (2009)
PNAS 106, 5041-5046
   Abstract »    Full Text »    PDF »
Submarine glacial landforms and rates of ice-stream collapse.
J.A. Dowdeswell, D. Ottesen, J. Evans, C. O Cofaigh, and J.B. Anderson (2008)
Geology 36, 819-822
   Abstract »    Full Text »    PDF »
Sea levels: resolution and uncertainty.
R. Edwards (2007)
Progress in Physical Geography 31, 621-632
   PDF »
Discovery of Till Deposition at the Grounding Line of Whillans Ice Stream.
S. Anandakrishnan, G. A. Catania, R. B. Alley, and H. J. Horgan (2007)
Science 315, 1835-1838
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

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