HR: 08:15h
AN: C41A-02    [PDF]
TI: Coupled Ice Shelf -- Ocean System Simulations for Different Climate Scenarios
AU: * Grosfeld, K
EM: grosfeld@palmod.uni-bremen.de
AF: Department of Geosciences/MARUM, University of Bremen, Klagenfurterstrasse, Bremen, 28334 Germany
AU: Sandh\"ager, H
EM: hsandhaeger@awi-bremerhaven.de
AF: Alfred Wegener Institute for Polar and Marine Research, Bussestrasse 24, Bremerhaven, 27570 Germany
AU: Lange, M A
EM: langema@uni-muenster.de
AF: Institute for Geophysics, University of M\"unster, Correnststrasse 24, M\"unster, 48149 Germany
AB: Based on a new approach for coupled applications of an ice shelf model and an ocean general circulation model, we investigate the evolution of an ice shelf - ocean system and its sensitivity to changed climatic boundary conditions. Combining established 3-d models into a coupled model system enables the investigation of reactions and feedbacks of each component to changes at their interface, the ice shelf base. After calculating the dynamics for prescribed initial ice shelf and bathymetric geometries, the basal mass balance determines the system evolution. In order to explore possible developments for given boundary conditions, an idealized geometry has been chosen, reflecting principle features of the Filchner-Ronne Ice Shelf, Antarctica. The model system is found to be especially sensitive in regions, where high ablation or accretion rates occur. Ice Shelf Water formation as well as the built up of a marine ice body, resulting from accretion of marine ice, is simulated, indicating strong interaction processes. Experiments under different climatic conditions (ocean warming of 0.2$^{\circ}$C and 0.5$^{\circ}$C and doubled surface accumulation rates) show the coupled model system to be sensitive especially to ocean warming. Increased basal melt rates of 100 % for the 0.5$^{\circ}$C ocean warming scenario and an asymmetric development of ice shelf thicknesses suggest a high vulnerability of ice shelf regions, which represent pivotal areas between the Antarctic Ice Sheet and the Southern Ocean.
DE: 1635 Oceans (4203)
DE: 1827 Glaciology (1863)
DE: 1863 Snow and ice (1827)
DE: 4207 Arctic and Antarctic oceanography
DE: 4255 Numerical modeling
SC: Cryosphere [C]
MN: 2003 Fall Meeting