Modelling of load-induced height changes in the southern Baltic for the last 8.000 years

• Applicant: Professor Dr.-Ing. Reinhard Dietrich
• Subject Area: Geophysics
• Term: from 2006 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 23633063

The aim of this project is the modelling of vertical crustal movements and of relative sea-level changes based on surface loading effects. The modelling will focus on the coastal region of the southern Baltic Sea and on realistic scenarios of selected sealevel evolution stages since the Littorina transgression. The impact of the spatially highly differentiated loading signal of the changing water masses in the course of the formation and filling of the Baltic Sea will be investigated. For this purpose, the Sea-Level Equation will be applied to the region under investigation, relating the closely linked contributions of eustasy, gravity and isostasy on relative sea-level changes. The isostatic vertical crustal deformation will be determined using a visco-elastic earth model, which is governed by a space-time load model including the changing land-sea distribution. In the proposed project, such a load model will be established as a downscaling of existing large scale models with unprecedented spatial and temporal resolution. This is possible due to the unique knowledge about changes in the sea level and shoreline position provided from SINCOS-II project 1, and which has recently been obtained from the multidisciplinary research within the SINCOS unit. Based on the enhanced load model, the associated response of the earth crust, gravity field, and relative sea level are quantified. The separation of the contributions of the Sea-Level Equation components to the observed sea-level changes is essential for any further modelling intended in project 1. In general, the solution of the Sea-Level Equation provides the basis for a refined interpretation and explanation of the relative sea-level curves available for the investigation area. Once the loading effects of sea-level changes in the past have been reconstructed, a prediction of future sea-level developments will be approached applying scenarios of the climatically driven eustatic changes.

• DFG Programme: Research Grants