Exploring the stability of the Antarctic Ice Sheet

Observations of ocean-driven grounding line retreat in the Amundsen Sea Embayment in Antarctica raise the question of an imminent collapse of the West Antarctic Ice Sheet. This would raise global sea levels by more than three metres. A collapse would be caused by irreversible retreat of the ice sheet’s grounding line – the position where the formerly grounded ice starts to float – due to a so-called Marine Ice Sheet Instability. Here we analyse whether Antarctic grounding lines are undergoing a Marine Ice Sheet Instability in their current position. Furthermore, we investigate the committed evolution of Antarctic grounding lines under present-day ocean and atmospheric conditions and put this into the paleo-context, in order to understand the current stability of the (West) Antarctic Ice Sheet.