Til bevillingsoversigt

Reconstructing ice dynamics in Dronning Maud Land, East Antarctica (RIDDLE)

Carlsbergfondets internationaliseringsstipendier

What

Ice masses on Earth are undergoing major changes. However, to relate these changes to a long-term climate perspective we rely on the geological record. Past volume changes of the East Antarctic Ice Sheet have been assessed through marine records, yet, a relatively untapped terrestrial source of information exists on ice-free mountains (nunataks) protruding the ice sheet. In this project, I will reconstruct past ice-sheet dynamics in the Dronning Maud Land sector of East Antarctica by performing detailed mapping of deposits and glacially carved landscapes on nunataks from satellite imagery and by dating the exposure age of rocks at the surface.

Why

The East Antarctic Ice Sheet is the largest ice sheet on Earth holding water corresponding to 58 m of sea-level equivalent. Although total collapse of the ice sheet is unlikely in the near future, even modest volume changes can have a significant impact on global sea level. By reconstructing past ice-sheet configurations we can improve our understanding of the complex links between climate, topography and ice in Antarctica. This project aims at providing a dataset to test and improve ice-sheet models, ultimately leading to better future ice-volume and sea-level change predictions.

How

Recent developments in remote sensing data from Antarctica enable mapping of landforms and deposits with an exceptional level of detail. I will focus on identifying subglacial landforms that indicate palaeo-ice flow directions contrasting with present-day ice-sheet flow patterns. The detailed geomorphological maps will provide insight into how regional ice flow has changed over time. To constrain the timing of past ice-sheet changes, I will analyse rare isotopes created by interaction with cosmic radiation in rock samples collected from nunataks in Dronning Maud Land. By analysing multiple cosmogenic isotopes, I can constrain potentially complex exposure- and burial histories.

SSR

This project has the potential to expand our knowledge of the sensitivity of the East Antarctic Ice sheet by providing a dataset to test and improve ice-sheet models. Such information is key in order to constrain future changes of the ice sheet in a warming climate. Improved sea-level change predictions can aid society to establish better socio-economic adaptation schemes.