DFG Priority Program SPP1257 "Mass Transport and Mass Distribution in the Earth System"
Antarctic ice-mass balance estimates from GRACE are highly contaminated by mass redistribution in the Earth's mantle associated with glacial-isostatic adjustment (GIA). Improving GIA corrections by integration of constraints recently available from GRACE and ICESat, as well as paleo sea-level indicators, into advanced three-dimensional global viscoelastic earth modelling is aim of this project.
The main goal of the study is construction of an integrated model of the Central Tien Shan, which is based on a joint analysis of the gravity, geodetic and other geophysical data. The obtained model should open a way for understanding of the ongoing tectonic processes forming this structure. In particularly, a new density model of the crust and upper mantle will be ob-tained in a joint inversion of the gravity field (including the GOCE data) and the new seismic data.
Global Modelling of the lithosphere and mantle and explaning geoid signal by merging of tomography derived mantle flow models with full thermal convection models including lateral viscosity variations
We continue the development of a new-generation global dynamic model of the crust and mantle, which is based on an integrative analysis of the gravity, GPS and other geophysical data. Based on the results obtained during the previous stages we focus on the following aspects.
- Development of an integrative model of the lithosphere (including a rheological model).
- Modelling of the effect of lateral viscosity variations in the mantle on the global geoid and surface plate velocities.
Since current GRACE results are still substantially affected by aliased signals originating from short-term mass variability in atmosphere, ocean and continental hydrosphere, the IMPLY projects attempts to reduce these effects by using improved numerical models for the de-aliasing process as well as by taking errors of these models into account. Section 1.3 in particular is focussed on the ocean's contributions to short-term mass variations.
The project VILMA is set up for the development of a numerical code, which enables the consideration of lateral variations of viscosity in the lithosphere and mantle for modelling of global deformations and gravity changes.