Gravity inversion as a method to recover sub-ice shelf bathymetry; applied to the Ross Ice Shelf

This poster was presented at the SCAR INSTANT 2023 conference in Trieste, Italy.

Abstract:

Sub ice-shelf bathymetry exerts a primary control on the stability of many Antarctic ice shelves through the geometry of pinning points and the guiding of melt-inducing water masses. Collecting sub-ice shelf bathymetry data using typical polar surveying methods (e.g. seismic surveying or direct observations) can be inefficient, expensive or unfeasible. Gravity inversions provide a more practical alternative, in which observed variations in Earth's gravitational field are used to predict the bathymetry. We have developed a new gravity inversion algorithm and associated workflow, available as an open-source Python package. Key features include several methods to separate the regional gravity field, various options to impose model regularization, and the ability to quantify spatially variable model uncertainties. Here, we implement this workflow to airborne gravity data from the Ross Ice Shelf and model the underlying bathymetry. Our results build upon the Tinto et al. 2019 model by using the new algorithm as well as incorporating additional gravity data and bathymetric constraints, collected since 2019.