Posts tagged esm advanced
VILMA (Viscoelastic Lithosphere and Mantle model)
- 29 May 2024
Volker Klemann and Maik Thomas
The topic of spectral finite-element code VILMA is the reduction of global GRACE, GPS and altimetry data with respect to the glacial-isostatic adjustment applying a 3D viscoelastic earth model. The model calculates the deformation of a viscoelastic and gravitating continuum in spherical domain, where lateral viscosity variations can be considered. Loading is prescribed as ice and ocean mass changes, which are determined consistently with respect to mass conservation, geoid changes and shoreline displacements by the sea-level equation. Code solves field equations of a spherical self-gravitating incompressible 3D-viscoelastic sphere with spectral–finite elements (Martinec 2000). GRD, that is rotational feedback and sea-level equation are solved for (Klemann et al. 2024 in prep.). Output are time-dependent changes in sea level, surface deformation and gravity potential in response to surface mass distribution. It is already coupled offline to PISM (Albrecht et al. 2024 in revision), MPI-ESM and AWI ESM and as compiled module in CLIMBER-X (Willeit et al. 2022). Offline coupling is implemented as exchange of two fields (in: ice load distribution; out: relative sea level).