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Ice sheet mass balance and sea level

Published online by Cambridge University Press:  01 October 2009

I. Allison ,
R.B. Alley ,
H.A. Fricker ,
R.H. Thomas  and
R.C. Warner
I. Allison*
Affiliation:
Australian Antarctic Division and Antarctic Climate and Ecosystems Cooperative Research Centre, Hobart, TAS 7050, Australia
R.B. Alley
Affiliation:
Department of Geosciences and Earth and Environmental Systems Institute, Pennsylvania State University, University Park, PA 16802, USA
H.A. Fricker
Affiliation:
Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
R.H. Thomas
Affiliation:
EG&G Technical Services Inc., Chincoteague, VA 23336, USA
R.C. Warner
Affiliation:
Australian Antarctic Division and Antarctic Climate and Ecosystems Cooperative Research Centre, Hobart, TAS 7050, Australia
*
*Ian.allison@aad.gov.au
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Abstract

Determining the mass balance of the Greenland and Antarctic ice sheets (GIS and AIS) has long been a major challenge for polar science. But until recent advances in measurement technology, the uncertainty in ice sheet mass balance estimates was greater than any net contribution to sea level change. The Fourth Assessment Report of the Intergovernmental Panel on Climate Change (AR4) was able, for the first time, to conclude that, taken together, the GIS and AIS have probably been contributing to sea level rise over the period 1993–2003 at an average rate estimated at 0.4 mm yr-1. Since the cut-off date for work included in AR4, a number of further studies of the mass balance of GIS and AIS have been made using satellite altimetry, satellite gravity measurements and estimates of mass influx and discharge using a variety of techniques. Overall, these studies reinforce the conclusion that the ice sheets are contributing to present sea level rise, and suggest that the rate of loss from GIS has recently increased. The largest unknown in the projections of sea level rise over the next century is the potential for rapid dynamic collapse of ice sheets.

Keywords

AntarcticaGreenlandmass budgetsea level rise
Type
Review
Information
Antarctic Science , Volume 21 , Issue 5 , October 2009 , pp. 413 - 426
Copyright
Copyright © Antarctic Science Ltd 2009

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