The marine geological imprint of Antarctic ice shelves

Widespread reductions in the thickness and extent of Antarctic ice shelves are triggering retreat, acceleration and increased discharge of marine-terminating glaciers. However, while the impacts of recent ice-shelf changes are now well documented, their role in modulating past ice sheet dynamics – especially at a resolution required to identify drivers of change and test ice sheet models - remains poorly constrained. This reflects two persistent issues: (i) the effective discrimination between sediments and landforms deposited in a sub-ice-shelf setting from other glacimarine environments, and (ii) challenges associated with dating these records. Here we summarise recent progress in deciphering the ‘geological imprint’ of Antarctic ice shelves, including important advances in dating methods and the proxies required to reconstruct the drivers of change. Despite this improved ‘toolbox’ for establishing ice shelf presence and absence, we recognise several challenges that need to be overcome if we are to fully exploit the palaeo record. Citation: Smith, J.A., Graham, A.G.C., Post, A.L. et al. The marine geological imprint of Antarctic ice shelves. Nat Commun 10, 5635 (2019). https://doi.org/10.1038/s41467-019-13496-5