[M-IS15] Global climate change driven by the Southern Ocean and the Antarctic Ice Sheet

[MIS15-P02] Interaction of the solid Earth and the Antarctic ice sheet

*Yoichi Fukuda¹, Koichiro Doi², Yuichi Aoyama², Yusuke Suganuma², Jun'ichi Okuno², Kazuki Nakamura³, Heitaro Kaneda⁴, Jun Nishijima⁵ (1.Department of Geophysics, Graduate School of Science, Kyoto University, 2.National Institute of Polar Research, 3.College of Engineering, Nihon University, 4.Department of Earth Sciences, Chiba University, 5.Department of Earth Resources Engineering, Graduate School of Engineering, Kyushu University)

Keywords:GIA, Antarctic ice sheet, Sea level rise

The Antarctic ice sheet, which relates to the global climate changes through the sea level rise and ocean circulation, is an essential element of the Earth system for predicting the future environment changes. Thus many studies of the ice sheet changes have been conducted by means of geomorphological, geological, geodetic surveys, as well as satellite gravimetry and satellite altimetry. However these studies thus far conducted have been affected by the large uncertainties of GlA (Glacial Isostatic Adjustment), which is the rheological response of the solid Earth to the ice mass loading. Therefore the precise estimation of the GIA effects is an urgent and an important task for these studies. The effects of GIA, on the other hand, include valuable information about the rheological properties of the solid Earth. Thus the observational studies of the GIA effects should greatly contribute to investigate the inner structure of the Earth. GIA, as a keyword to investigate the interaction between the solid Earth and the ice sheet changes, is an important research target not only for a practical requirement of predicting global changes but also for a more pure scientific interest to know the structures of the deep Earth's interior.
In view of these points, we plan to conduct geomorphological, geological and geodetic surveys in the inland mountain areas and the coastal areas in East Antarctica, where the in-situ data for constraining GIA models are very few. In addition, we will conduct precise monitoring of the land movements at Syowa Station using space geodetic observations such as SLR (Satellite Laser Ranging) and VLBI (Very Long Baseline Interferometer) as well as sea bottom geomorphological surveys on continental shelves using new technology of ROV (Remotely operated Vehicle) and AUV (Autonomous Underwater Vehicle). Combining these observations with the analyses of the sea bottom cores obtained by the bowling surveys on the continental shelves, various satellite data analyses and numerical modeling, we will precisely estimate the response of the solid Earth due to the GIA effects and corresponding sea level changes. These procedures lead us to a precise GIA model and constructing a reliable ice melting history after LGM (the Last Glacial Maximum) and the viscoelastic structure of the Earth's interior.
We will present the outline of this research project.