Item

Abstract

Establishing a geodynamically consistent solid-earth model component is essential to realistically simulate changes in earth deformation due to ice-load changes (GIA). For the implementation of a viscoelastic lithosphere and mantle into an earth system model, uncertainties in earth deformation due to earth structure variability and glaciation history variability have to be quantified. Using the global numerical model VILMA, we investigate the sensitivity of these two aspects on surface deformation and on the reconstruction of sea-level change. In a series of model simulations, key parameters of the earth’s viscosity structure and the possible range of ice-sheet distributions are varied. The resulting variability is analyzed in a spatial-temporal context. In addition to assess the variability at the ice margins which feeds back to the ice dynamics, we investigate the far-field response which is influenced by the paleo topography/bathymetry and, so, has an impact on ocean dynamics and coastal environments. This study is part of the ‘German climate modeling initiative’ PalMod which aims at modeling, understanding and quantification of feedbacks between climate components during the last glacial cycle.