Geodetic observations for constraining mantle processes in Antarctica

Abstract Geodynamic processes in Antarctica such as glacial isostatic adjustment (GIA) and post-seismic deformation are measured by geodetic observations global navigation satellite systems (GNSS) gravimetry. GNSS measurements have comprised both continuous episodic since the mid-1990s. The estimated velocities typically reach an accuracy of 1 mm a −1 for horizontal 2 vertical velocities. However, elastic due to present-day ice-load change needs be considered accordingly. Space gravimetry derives mass changes from small variations inter-satellite distance pair satellites, starting with GRACE (Gravity Recovery Climate Experiment) mission 2002 continuing GRACE-FO (GRACE Follow-On) launched 2018. spatial resolution is low (about 300 km) but measurement error homogeneous across Antarctica. trends contain signals ice-mass change, local GIA signals. To combine strengths individual datasets, statistical combinations GNSS, altimetry data been developed. These rely on realistic estimates assumptions snow density. Nevertheless, they capture that missing geodynamic forward models large uplift Amundsen Sea sector caused low-viscous response century-scale changes.