[M-IS03] The Southern Ocean and the Antarctic Ice Sheet dynamics in past, present and future

[MIS03-P02] Refined Antarctic Ice Sheet changes inferred from GIA modeling and geological observations in East Antarctica

*Takeshige Ishiwa¹, Jun'ichi Okuno^2,1, Yusuke Suganuma^1,2 (1.National Institute of Polar Research, 2.The Graduate University for Advanced Studies (SOKENDAI))

Keywords:GIA modeling, Antarctica, Sea-level changes

The Antarctica Ice Sheet (AIS) mass loss is now contributing and will significantly contribute to global sea-level rise. The AIS changes with various timescales, monthly to hundreds of thousands of years. Satellite and geodetic observations are useful approaches to detect the relatively short-term variability of the AIS. Besides, a combination of model simulations and geological evidence is a powerful method for understanding the much longer timescale of AIS. However, there is a discrepancy between modeling results and geological observations. We will present a reconstruction of the East AIS changes from Last Interglacial to present based on glacial isostatic adjustment (GIA) modeling and geological evidence. Sea-level records in Lützow-Holm Bay, East Antarctica, spread Holocene and Marine Isotope Stage 3 (Miura et al., 1998; Takano et al., 2012; Verleyen et al., 2017). In addition, the surface exposure dates indicate the rapid melting during the Holocene (Kawamata et al., 2020). We refined the ice loading history as the input parameter of GIA modeling to explain the geological evidence. We will present the refined AIS histories from the Last Interglacial to the present and the future plans of this study.

Reference
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Kawamata, M., et al., 2020, Quaternary Science Reviews, 247, 106540.
Miura, H., et al., 1998, vol. 6. Special map series of National Institute of Polar Research, 46.
Takano, Y., et al., 2012, Applied Geochemistry, 27, 2546–2559.
Verleyen, E., et al., 2017,Quaternary Science Reviews, 169, 85–98.