PANGAEA_982379 Sedimentological, geochemical and sediment-physical analysis of eight sediment cores from the Mac. Robertson Shelf, East Antarctica Güntzel, Janina; Müller, Juliane; Lembke-Jene, Lester; Tiedemann, Ralf; Mollenhauer, Gesine; Klages, Johann Philipp Sedimentological, geochemical and sediment-physical analysis of eight sediment cores from the Mac. Robertson Shelf, East Antarctica 2026-06-29 PANGAEA Dataset https://doi.pangaea.de/10.1594/PANGAEA.982379 Earth Science geoscientificInformation Antarctic Shelf East Antarctica Polarstern Radiocarbon ages Sedimentology-marine cores 2022-02-09 2022-02-10 Complete -67.142285 -66.828596 63.18823 65.81721 access rights needed CC-BY-4.0: Creative Commons Attribution 4.0 International (License comes into effect after moratorium ends) English PANGAEA Data Publisher for Earth & Environmental Science https://www.pangaea.de/ Data Center Contact Michael Diepenbroek info@pangaea.de

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Bremen Bremen 28359 Germany online 14 datasets application/zip Güntzel, Janina; Müller, Juliane; Tiedemann, Ralf; Mollenhauer, Gesine; Lembke-Jene, Lester; Weigelt, Estella; Schopen, Lasse; Wesch, Niklas; Kattein, Laura; Mackintosh, Andrew; Klages, Johann Philipp (2026): Last Glacial Maximum extent and subsequent retreat of the East Antarctic Ice Sheet from the Mac. Robertson Shelf. The Cryosphere, 20(7), 3739-3758, https://doi.org/10.5194/tc-20-3739-2026

The future behavior of the Antarctic Ice Sheet is considered to be one of the largest uncertainties in global climate projections, with its stability fundamentally governed by grounding-zone processes, bed geometry, and sensitivity to oceanic forcing. However, observational records only reflect a short moment when considering the length of a full cycle of ice sheet expansion and retreat. Therefore, paleo-data present a valuable extension to the observational period. East Antarctica's deglaciation history remains largely understudied compared to the West Antarctic margin. This emphasizes the urgent need for reliable long-term spatiotemporal data on ice sheet change, particularly for sectors that play key roles in supplying the world's oceans with dense bottom water. In this study, we performed a multi-proxy analysis on geophysical and geological data recovered from two prominent glacial cross-shelf troughs on the Mac. Robertson continental shelf. We classified submarine glacial landforms on the continental shelf along both troughs from combined multibeam swath bathymetry and sub-bottom profiler data to infer past grounding line extent and the pattern of subsequent grounding line retreat. Additionally, combined sedimentological, sediment-physical, and geochemical analyses, including foraminifer radiocarbon dating, reveal the style and timing of this retreat across the shelf. Our study concludes that grounded ice reached the Mac. Robertson continental shelf break until just before ~12.7 cal. ka BP, hence preventing the formation of Dense Shelf Water (DSW) in its current form. We therefore infer a different formation mechanism for DSW as an important precursor of Antarctic Bottom Water under such full glacial conditions before continued grounding-line retreat exposed the middle continental shelf by ~10.8 cal. ka BP and set the stage for more modern-like conditions. ** For all details see the full metadata description at "https://doi.pangaea.de/10.1594/PANGAEA.982379"!

https://doi.org/10.5194/tc-20-3739-2026 Last Glacial Maximum extent and subsequent retreat of the East Antarctic Ice Sheet from the Mac. Robertson Shelf DIF 9.4 2026-06-29 2026-07-03