Large obliquity-paced Antarctic ice-volume fluctuations suggest melting by atmospheric and ocean warming during late Oligocene

• Verfasst von: Brzelinski, Swaantje [VerfasserIn]
• Verfasst von: Bornemann, André [VerfasserIn]
• Verfasst von: Liebrand, Diederik [VerfasserIn]
• Verfasst von: van Peer, Tim E. [VerfasserIn]
• Verfasst von: Wilson, Paul A. [VerfasserIn]
• Verfasst von: Friedrich, Oliver [VerfasserIn]
• Titel: Large obliquity-paced Antarctic ice-volume fluctuations suggest melting by atmospheric and ocean warming during late Oligocene
• Verf.angabe: Swaantje Brzelinski, André Bornemann, Diederik Liebrand, Tim E. van Peer, Paul A. Wilson & Oliver Friedrich
• Jahr: 2023
• Umfang: 8 S.
• Illustrationen: Illustrationen
• Fussnoten: Veröffentlicht: 22. Juni 2023 ; Gesehen am 03.08.2023
• Titel Quelle: Enthalten in: Communications earth & environment
• Ort Quelle: London : Springer Nature, 2020
• Jahr Quelle: 2023
• Band/Heft Quelle: 4(2023), Artikel-ID 222, Seite 1-8
• ISSN Quelle: 2662-4435
• DOI: doi:10.1038/s43247-023-00864-9
• Datenträger: Online-Ressource
• Sprache: eng
• Sach-SW: Cryospheric science
• Sach-SW: Palaeoceanography
• Sach-SW: Palaeoclimate
• K10plus-PPN: 1854262424
• K10plus-PPN:
  Universitätsbibliothek
• Lokale URL UB: Zum Volltext

Abstract

The late Oligocene (~27.8-23 My ago) offers an opportunity to study past climate variability under high-CO2, warmer-than-present and the unipolar (Antarctic) glaciated state. Here, we present new high-resolution geochemical records from exquisitely well-preserved benthic foraminifera for the late Oligocene, an interval for which Antarctic ice-sheet size and stability are debated. Our records indicate four obliquity-paced glacial-interglacial cycles with ice-volume changes of up to ~70% of the modern Antarctic ice-sheet. The amplitude of ice-volume change during these late Oligocene glacial-interglacial cycles is comparable to that of the late Pliocene and early Pleistocene. Ice-volume estimates for interglacials are small enough to be accommodated by a land-based Antarctic ice-sheet but, for three of the four glacials studied, our calculations imply that ice sheets likely advanced beyond the Antarctic coastline onto the shelves. Our findings suggest an Antarctic ice-sheet vulnerable to melting driven by both bottom-up (ocean) and top-down (atmospheric) warming under late Oligocene warmer-than-present climate conditions.