Propagating Antarctic ice shelf collapse in Holocene driven by meltwater release

Circumpolar Deep Water (CDW) inflow onto the Antarctic continental shelf is a key driver of accelerated Antarctic Ice Sheet (AIS) mass loss1-3, both presently4 and during the last deglaciation5,6. However, the mechanisms for enhanced CDW inflow and its impact to the large-scale AIS retreats are still not fully understood. Here, we provide sediment core evidence from sedimentary beryllium isotope and multi-proxy analysis, that ice shelf collapse and simultaneous inland ice sheet thinning around 9,000 years ago was associated with enhanced CDW inflow and sea level rise in Lutzow-Holm Bay (LHB), East Antarctica. A hierarchical modeling approach that combines climate7 and high-resolution ocean simulations8 suggests that freshwater discharge from adjacent sectors of the AIS to the Southern Ocean likely enhanced the regional CDW inflow into submarine troughs in LHB between 10,000 and 9,000 years ago. We propose that a series of tipping points propagated around the Antarctic margin during the last glacial termination, underscoring the importance of the feedback between meltwater input, CDW incursions onto the continental shelf, ice shelf stability, and ice sheet dynamics, alongside relative sea level rise, for both historical and future AIS changes.