GNSS Observations of GIA‐Induced Crustal Deformation in Lützow‐Holm Bay, East Antarctica

Abstract

AbstractThe Japanese Antarctic Research Expeditions have conducted long‐term Global Navigation Satellite System (GNSS) observations at a series of bedrock outcrops along the coast of Lützow‐Holm Bay, East Antarctica, to elucidate the solid Earth response to ice mass changes. These GNSS observations capture both the viscoelastic response of the solid Earth to Antarctic Ice Sheet changes since the Last Glacial Maximum, termed glacial isostatic adjustment (GIA), and elastic deformation associated with recent surface mass changes due to snowfall variations. Here, we extract the GIA signals from the Lützow‐Holm Bay GNSS data by applying an elastic deformation correction based on the mass fluctuations observed in the Gravity Recovery and Climate Experiment and the satellite altimetry. Our results indicate that the region is currently experiencing approximately 1 mm/yr of subsidence, which is large enough to influence GIA model estimations. The resultant GIA‐induced deformation response in Lützow‐Holm Bay is 1–6 mm/yr of uplift.