Refined broad-scale sub-glacial morphology of Aurora Subglacial Basin, East Antarctica derived by an ice-dynamics-based interpolation scheme

Ice thickness data over much of East Antarctica
are sparse and irregularly distributed. This poses difficulties
for reconstructing the homogeneous coverage needed to
properly assess underlying sub-glacial morphology and fundamental
geometric constraints on sea level rise. Here we
introduce a new physically-based ice thickness interpolation
scheme and apply this to existing ice thickness data in the
Aurora Subglacial Basin region. The skill and robustness of
the new reconstruction is demonstrated by comparison with
new data from the ICECAP project. The interpolated morphology
shows an extensive marine-based ice sheet, with
considerably more area below sea-level than shown by prior
studies. It also shows deep features connecting the coastal
grounding zone with the deepest regions in the interior. This
has implications for ice sheet response to a warming ocean
and underscores the importance of obtaining additional high
resolution data in these marginal zones for modelling ice
sheet evolution.

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