- 1Imperial College London, Earth Science and Engineering, United Kingdom of Great Britain – England, Scotland, Wales (jwm17@ic.ac.uk)
- 2Laboratory for Provenance Studies, Department of Earth and Environmental Sciences, University of Milano-Bicocca, Milano, Italy.
- 3Department of Earth Sciences, Binghamton University, State University of New York, Binghamton, NY, USA.
- 4GNS Science, Lower Hutt, New Zealand.
- 5Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung, Am Alten Hafen 26, Bremerhaven, Germany.
- 6State Key Laboratory of Marine Geology, Tongji University, Shanghai, China.
- 7Division of Glacial Environment Research, Korea Polar Research Institute, Incheon, Republic of Korea.
- 8Department of Earth, Geographic, and Climate Sciences, 627 N. Pleasant St., Amherst, MA, USA.
- 9School of Geography Geology and Environment, University of Leicester, Leicester, UK.
- 10Geological Survey of Japan, The National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan.
- 11Institute of Low Temperature Science, Hokkaido University, Sapporo, Japan.
- 12Institute of Geosciences, Christian-Albrechts-University of Kiel, Kiel, Germany.
- 13London Geochronology Centre, Department of Earth Sciences, University College London, London, UK.
- 14Department of Earth and Planetary Sciences, Birkbeck University of London, Malet Street, London, UK.
- 15Centre for Geography and Environmental Sciences, University of Exeter, Cornwall, UK.
- *A full list of authors appears at the end of the abstract
The warmer-than-present interglacial periods of the late Pleistocene provide the closest palaeo analogues to inform predictions of Antarctic ice sheet mass loss over the coming decades and centuries. However, the response of Antarctica’s ice sheets to environmental conditions during these interglacial periods remains poorly constrained, resulting in significant uncertainties in ice sheet model predictions of future sea-level rise. Here, sediment provenance analyses (Nd and Sr isotope compositions, detrital zircon U-Pb dates and heavy mineral counts) reveal changes to ice sheet extent in the Ross Sea over the glacial-interglacial cycles of the last ~400 kyr at International Ocean Discovery Program (IODP) Site U1524.
Glacial periods show a broadly mixed East/West Antarctic provenance signature, consistent with an ice sheet grounded across most of the Ross Sea continental shelf that reworked older sediments. In contrast, interglacial intervals - including the Holocene - consist primarily of sediment derived from West Antarctica, suggesting westward transport by ocean currents dominates sediment delivery to the site. Detailed examination of these West Antarctic sourced intervals reveals a consistent pattern of provenance change over the course of each interglacial examined. East Antarctic-derived sediment is only dominant at the site for two short-lived intervals just after two interglacial periods, thought to be Marine Isotope Stage (MIS) 11 and MIS 9 based on the current age model. These intervals may record a transient ice sheet configuration in the earliest part of each glacial period where the Ross Ice Shelf had grown to a larger-than-present size, whilst the grounding zone had not yet advanced far beyond its present-day location. Critically, each of these two East Antarctic dominated intervals displays different provenance characteristics, implying differing ice flow patterns in the Ross Ice Shelf and therefore different ice sheet extents in the preceding interglacials. This suggests Antarctica’s ice sheets are sensitive to the relatively subtle differences in climate seen in recent interglacial periods.
Jamie O'Neill, J.ONeill2@exeter.ac.uk, affiliation code 15. Benjamin Keisling, keisling@ldeo.columbia.edu, affiliation code 16. Laura DeSantis, ldesantis@ogs.it, affiliation code 17.
How to cite: Marschalek, J., Pastore, G., van de Flierdt, T., Patterson, M., McKay, R., Holder, L., Grant, G., Mueller, J., Xiao, W., Kim, S., Cortese, G., Bombard, S., Leckie, R. M., van Peer, T., Sugisaki, S., Seki, O., Kulhanek, D., Vermeesch, P., Carter, A., and Gasson, E. and the Additional authors: Evidence for West Antarctic Ice Sheet sensitivity to different recent Pleistocene interglacial climates, EGU General Assembly 2025, Vienna, Austria, 27 Apr–2 May 2025, EGU25-17938, https://doi.org/10.5194/egusphere-egu25-17938, 2025.