|East Antarctic ice sheet most vulnerable to Weddell Sea warming|
|investigators:||N. Golledge and others|
|journal:||Geophysical Research Letters|
In practice, ice sheet models need to be re-run many times with slightly-altered parameters. This short paper describes the results of an ensemble of 42 PISM runs for the entire Antarctic ice sheet (AIS), starting from present-day conditions, each for 10,000 model years, to see which sectors of the continent are most affected by warming. The runs vary only in atmospheric (air temperature anomaly) and oceanic (sea surface temperature anomaly) warming.
The results are clear and consistent when examined at drainage basin scale (Zwally et al 2012). The basins of the West Antarctic Ice Sheet (WAIS) show strong sensitivity to a modest amount of ocean warming, with a 0.5 C anomaly generating an essentially-complete collapse of WAIS, just as expected from other observational and simulation evidence. In the East (EAIS), however, the Recovery ice stream basin stands out as sensitive to both kinds of warming. Other EAIS basins such as Wilkes and Aurora are sensitive to atmospheric heat inputs but much less so to oceanic inputs.
The 4000 square km ice field in Southeast Alaska is well-known and accessible since its outlets are in the suburbs of the Alaska state capital, Juneau. But climate data for the area are sparse.
Those model runs that agreed well with observations for 1971 to 2010 generated volume and area losses of more than half by 2099. While co-author Regine Hock (UAF) is quoted as saying “The massive icefield that feeds Alaska’s Mendenhall Glacier may be gone by 2200 if warming trend predictions hold true,”, the authors emphasize that spatially-distributed mass balance measurements and improved climate projections that resolve the local temperature and precipitation patterns are essential to solidifying these predictions.
Please acknowledge the funding that makes PISM possible, and which supports its continued maintenance and technical support. Include the sentence “Development of PISM is supported by NASA grants NNX13AM16G and NNX13AK27G.” in the Acknowledgments part of your paper.
If authors do this consistently then it will help to ensure continued funding of PISM!
For specific suggestions on how to cite the design or justification of PISM see this page.
The Paleoclimate Dynamics section at Alfred-Wegener-Institut invites applications for a position as a
with a background in ice sheet or climate modelling for the DFG-project “Global sea level change since the Mid Holocene” (SPP 1889).
Background and tasks:
The aim of this project is to study the evolution of polar ice sheets of the last 6000 years and to estimate the role of climate – ice sheet interactions. Combining climate and ice sheet simulations of different resolution, the project particularly focusses on the ice sheets' mass balance and on ice shelf – ocean interactions under natural and anthropogenic climate change.
The postdoc’s duties will include set-up, supervision, and analysis of climate and ice sheet (PISM) simulations as well as publication in peer-reviewed journals.
The successful candidate should have a PhD in glaciology, atmospheric sciences, oceanography or related sciences and should have a background in either ice sheet or climate modelling.
The position is limited to 3 years, starting August 1st, 2016 or later. The salary will be paid in accordance with the German Tarifvertrag des öffentlichen Dienstes (TVöD Bund), salary level 13. The place of employment will be Bremerhaven.
For further information:
PISM is jointly developed at the University of Alaska, Fairbanks (UAF) and the Potsdam Institute for Climate Impact Research (PIK). For more about the team see the UAF Developers and PIK Developers pages.
UAF developers, who are in the Glaciers Group at the GI, are supported by NASA's Modeling, Analysis, and Prediction and Cryospheric Sciences Programs (grants NAG5-11371, NNX09AJ38C, NNX13AM16G, NNX16AQ40G, NNX17AG65G) and by NSF grants PLR-1603799 and PLR-1644277.