Review: Ice sheet mass balance and sea level

• Published in: Antarctic Science
• Main Authors: Allison, I, Alley, RB, Fricker, HA, Thomas, RH, Warner, RC
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge Univ Press 2009
• Subjects: Earth Sciences; Physical Geography and Environmental Geoscience; Glaciology; Antarctic; Greenland; Antarc*; Antarctic Science; Ice Sheet
• Online Access: https://doi.org/10.1017/S0954102009990137; http://ecite.utas.edu.au/100644

Determining the mass balance of the Greenland and Antarctic ice sheets (GIS and AIS) has longbeen a major challenge for polar science. But until recent advances in measurement technology, theuncertainty 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 thefirst time, to conclude that, taken together, the GIS and AIS have probably been contributing to sea levelrise over the period 19932003 at an average rate estimated at 0.4mm yr-1. Since the cut-off date for workincluded in AR4, a number of further studies of the mass balance of GIS and AIS have been made usingsatellite altimetry, satellite gravity measurements and estimates of mass influx and discharge using a varietyof techniques. Overall, these studies reinforce the conclusion that the ice sheets are contributing to presentsea level rise, and suggest that the rate of loss from GIS has recently increased. The largest unknown in theprojections of sea level rise over the next century is the potential for rapid dynamic collapse of ice sheets.