Ice-Sheet and Solid-Earth Dynamics

Ilullisat Icefjord (Jakobshavn Isbrae), Disko Bay, West Greenland. © I Sasgen

The topic Ice-Sheet and Solid-Earth Dynamics focuses on the numerical simulation of transient dynamics and interaction of the oceans, the cryosphere and the solid earth, which are coupled by surface loading, gravitational attraction and exchange of mass and momentum. Signatures of these processes contribute to the main long-term signals in geodetic and geophysical observations and their quantification are one important task in deciphering ongoing long-term processes from present-day processes which are associated with man-made influences on the Earth's climate system.

One of the main ongoing mass-redistribution processes of global influence are the ice ages resulting in the glacial isostatic adjustment (GIA), which is the reaction of the solid earth and oceans to these periodic glaciations at the earth's surface during the last Million years. Furthermore, melting of glaciers during the last centuries and present ice sheets-dynamics are investigated.

Improvements in geodetic observation techniques and systems during the last two decades (GPS and satellite gravimetry) enable to identify these processes in geodetic signals with unprecedented accuracy and, therefore, calls for quantitative predictions in order to distinguish them from other climate and geodynamically driven processes.

Climate, ice-sheet dynamics and solid-earth dynamics are the mandatory ingredients to quantify GIA and present ice-mass changes. The focus lies on the numerical modelling of the ice-sheet dynamics in response to climate variability, the modelling of the solid-earth response to surface-mass changes and their gravitationally consistent coupling which demands the consideration of the ocean response in sea level. Furthermore, we aim to constrain earth and ice models by means of geomorphological indicators of ice extension, by sea-level indicators and by geodetic observations.

Solid-earth dynamics and ice-sheet dynamics are dominated by the rheological properties of their fabric. This demands a close cooperation with material sciences and in case of the solid earth with geodynamical and seismological constraints, and their mutual relations.

The interpretation of geomorphological and geological indiciators demands close cooperation with geological sciences and close collaboration with the geodetic sections of this department in order to reconstruct a better constrained glaciation history and to quantify present and future mass changes in the prominent ice sheets of Antarctica and Greenland.

Contact

Profile photo of  Dr. Volker Klemann

Dr. Volker Klemann
Earth System Modelling

Telegrafenberg
Building A 20, room 314
14473 Potsdam
tel. +49 331 288-1104