Climate Science

Greenland's Going Rate

+ See all authors and affiliations

Science  29 Apr 2011:
Vol. 332, Issue 6029, pp. 515
DOI: 10.1126/science.332.6029.515-c
CREDIT: ISTOCKPHOTO

One of the most potentially important consequences of global warming is sea-level rise. The Greenland Ice Sheet is expected to be the source of much of the meltwater that raises sea level in the near term, but how much mass loss it will experience in a warmer future is difficult to say with confidence, due largely to the difficulty of modeling the dynamic behavior of the ice-sheet as air and sea temperatures rise. Ren et al. present results from a multiphase, multiple-rheology, scalable and extensible geofluid ice-sheet model that has been designed specifically with that problem in mind. Their model incorporates full Navier-Stokes equations to account for nonlocal dynamic balance and ice flow, and a granular sliding layer between the ice and bedrock to allow large-scale surges like those that are commonly observed now. Forcing their model with monthly atmospheric conditions provided by high-resolution climate simulations, they project that the rate of Greenland Ice Sheet mass loss could reach as high as 220 km3/year by 2100, significantly exceeding estimates by the IPCC AR4 of ∼50 to 100 km3/year, which were made without considering the dynamic behavior of the ice sheet.

J. Clim. 10.1175/2011JCLI3708.1 (2011).

Navigate This Article