Southern Ocean evidence for recurring West Antarctic Ice Sheet destabilization during Marine Isotope Stage 11.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41093831.
- Also identified by DOI 10.1038/s41467-025-65002-9 and PMC identifier 12528459.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Millennial-scale deoxygenation of Antarctic Bottom Water (AABW) in the Atlantic Southern Ocean during past interglacials was linked to West Antarctic Ice Sheet (WAIS) melt-driven suppression of dense water formation along the Antarctic margin. However, the circum-Antarctic extent of these 'AABW stagnation events' and drivers of WAIS retreat remain unclear. Here, we identify recurring bottom water O<sub>2</sub> minima in the central Pacific Southern Ocean during Marine Isotope Stage (MIS) 11 (424-374 ka ago) that are synchronous with their Atlantic Southern Ocean counterparts. As they (partially) align with Circumpolar Deep Water (CDW) warming above present-day levels and/or a reorganization of deep-ocean circulation, we postulate recurring and synchronized Pacific-Atlantic AABW perturbation events during MIS11 through WAIS retreat and enhanced exposure to ocean heat (i.e., CDW) from below. This indicates a significant contribution of WAIS meltwater to sea-level high-stands during MIS11 and, by analogy, to sea-level rise due to ocean warming in the future.