Self-inhibiting growth of the Greenland Ice Sheet

Published: Dec 1, 2012 by The PISM Authors


Title	Self-inhibiting growth of the Greenland Ice Sheet
Authors	Peter Langen and others
Venue	Geophysical Research Letters

The build-up of the Greenland Ice Sheet from ice-free conditions is studied using PISM driven by fields from an atmospheric GCM. Experiments where the two are coupled off-line are augmented by one where an intermediate ice sheet configuration is coupled back to the GCM. The ice sheet regrows from the ice-free state but this is halted when the intermediate recoupling step is included. This inhibition of further growth is due to a Föhn effect of moist air parcels being lifted over the intermediate ice sheet and arriving in the low-lying Greenland interior with high temperatures. This demonstrates that two-way coupling between the atmosphere and the ice sheet is essential for understanding its dynamics. Conditions cooler than those of today may be necessary for the GrIS to regrow to the present volume.

A two-year PostDoc positions in ice sheet and Earth system modelling is available in the Ice Dynamics group, as part of the new Earth Resilience Science Unit (ERSU), at the Potsdam Institute for Climate Impact Research (PIK).

Two PhD fellowship positions in ice sheet modelling are advertised at the Niels Bohr Institute, University of Copenhagen.

The Alfred Wegener Institute, Bremerhaven, is offering a PhD position in the field of coupled ice sheet-ocean modelling. The core of the project is to run simulations with FESOM-PISM (a coupled ocean-ice shelf-ice sheet model with evolving cavity geometries) for different 21st-century climate projections to obtain well-constrained trajectories of future ice mass loss from the vast Antarctic Ice Sheet. Model results will feed into a fingerprinting method that considers the ocean response as well as gravitational effects and contributions from other sources. The final product will be a time series of global maps of regional sea-level variations that consider all of the most relevant processes.