Abstract
Constraining past West Antarctic Ice Sheet (WAIS) change helps validate numerical models simulating future ice sheet dynamics. Following rapid deglaciation during the mid-Holocene, ice near Thwaites Glacier was ∼35 m thinner than present; however, the timing of ice regrowth to its present configuration remains unknown. To fill this knowledge gap, we present cosmogenic nuclide exposure ages of cobbles from the surface of a moraine situated between Thwaites and Pope glaciers. We infer that the moraine formed and stabilized in the Late Holocene (∼1.4 ka) when a small glacier thickened. We also present a novel reconstruction of WAIS volume constrained by sea-level data, which demonstrates that moraine formation coincided with a large-scale WAIS readvance. Our new geologic constraints will help inform models of the solid Earth response to surface mass loading, improving our understanding of ice sheet dynamics in a vulnerable part of WAIS.
Original language | English |
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Article number | e2024GL110350 |
Number of pages | 11 |
Journal | Geophysical Research Letters |
Volume | 51 |
Issue number | 24 |
Early online date | 19 Dec 2024 |
DOIs | |
Publication status | Published - 28 Dec 2024 |
Keywords
- Holocene
- Thwaites glacier
- geochronology
- glacial geology
- readvance
- west Antarctic Ice Sheet