Slides: Addressing bathymetry uncertainty beneath the Ross Ice Shelf

Abstract

These slides were presented at the 2023 New Zealand Australia Antarctic Science Conference in Christchurch, NZ.Abstract:The bathymetry underlying Antarctica’s Ross Ice Shelf exterts a strong control on it’s stability. The bathymetry guides the circulations of melt-inducing water masses and defines the geometry of pinning points. 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. Here we present a gravity inversion algorithm designed specificy to model sub-ice shelf bathymetry. 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 use this inversion with 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.Gravity Inversion Github Repository: https://github.com/mdtanker/RIS_gravity_inversion</p