07 January 2014

Greenland Ice Sheet surface mass balance variability increases under anthropogenic climate change.


 The Greenland Ice Sheet gains and loses mass at the surface through snow accumulation in the interior and ice melt at the margins. The net amount mass gained or lost at the surface over the course of a year is termed the surface mass balance, and is a major control on Greenland Ice Sheet evolution. Greenland surface mass balance is highly variable year to year; this variability can impact regional climate, ice sheet dynamics, and the assessment of Greenland ice loss trends. DOE researchers have carried out a surface mass balance variability analysis of a Community Earth System Model (CESM) simulation with Greenland surface mass balance calculations included, to assess changes to Greenland surface mass balance variability from 1850 to 2100. They found a large and significant increase to overall Greenland surface mass balance sensitivity, and tracked this increase to growth of the high-variability zone of the ice sheet where ice is lost (the ablation zone). These findings highlight that increased Greenland Ice Sheet surface mass balance variability is a physically consistent response to anthropogenic climate change, in line with findings of similarly increased variability within other components of the Earth system in a warming world.

Jeremy G Fyke
Los Alamos National Laboratory (LANL)
Fyke, JG, M Vizcaino, WH Lipscomb, and S Price.  2013.  "Future Climate Warming Increases Greenland Ice Sheet Surface Mass Balance Variability."  Geophysical Research Letters n/a, doi:10.1002/2013GL058172.

 The authors thank William Sacks and Nathan Urban for use- ful contributions, and the Editor Julienne Stroeve, reviewer Jan Lenaerts, and another anonymous reviewer for many insightful critiques. This work was supported by the Earth System Modeling and Regional and Global Climate Modeling programs of the Office of Biological and Environmental Research within the US Department of Energy Office of Science.