Ocean cavity regime shift reversed West Antarctic grounding line retreat in the late Holocene

Recent evidence suggests the Siple Coast grounding line of the West Antarctic Ice Sheet (WAIS) retreated significantly in the mid-to-late Holocene and then readvanced. This study investigates whether changing isostatic rebound rates or regional climate change caused this reversal using ice sheet model simulations with varying ocean thermal forcing and global glacioisostatic adjustment (GIA) models. Results indicate a warm-to-cold ocean cavity regime shift as the most likely cause, with GIA influencing the ice sheet's response rate to oceanic changes. This highlights the grounding line's sensitivity to future sub-ice shelf ocean circulation changes.

Daniel P. Lowry, Holly K. Han, Nicholas R. Golledge, Natalya Gomez, Katelyn M. Johnson, Robert M. McKay