Palaeo-ice sheet dynamics

The overarching goal of our working group is to better understand the long-term dynamics of global ice sheets. Their influence on the climate system and the direct control of global sea levels are the two most important cornerstones. We conduct marine geological research in the Arctic and Antarctic to

• more precisely define the inadequately known advance and retreat behavior of the Antarctic ice sheet in the alternation of past warm and cold periods. The current focus is on the West Antarctic ice sheet, which is situated primarily below sea level and is therefore inherently unstable. It is currently strongly retreating and, if it continues to retreat, would have the potential to cause global sea level to rise by several meters. Future focus regions are continental shelves that lie in front of areas of the East Antarctic ice sheet situated below sea level and whose former behavior is almost entirely unknown.

• better understand marine and terrestrial Antarctic environmental conditions in order to define the driving mechanisms for the growth and retreat of ice sheets

• more clearly define the extent of the northern hemisphere ice sheet during past glacial periods, and

• to assess the still controversial presence of inland ice during the Last Glacial Maximum (LGM; ~ 20,000 years before today) in Eastern Siberia / Beringia.

By applying detailed combined investigation of seabed sediment cores, high-resolution bathymetric maps, and sediment echographic seabed profiles, our employees are able to create a reliable four-dimensional image of past ice sheet dynamics at local, regional, and "ice sheet-wide" scale. This palaeoglaciological information from a wide variety of research areas directly contributes to better reconstructing the history of global ice sheets and evaluating their influence on ocean circulation and sea level variations. As a result, models for future ice sheet behavior are then to be tested, validated and ultimately improved using this data. To this end, we not only work closely with various other working groups at the AWI, but are of course also closely networked with national and international institutes and universities.