Articles | Volume 9, issue 1
Earth Syst. Sci. Data, 9, 267–279, 2017
Earth Syst. Sci. Data, 9, 267–279, 2017

Brief communication 05 May 2017

Brief communication | 05 May 2017

A high-resolution synthetic bed elevation grid of the Antarctic continent

Felicity S. Graham1, Jason L. Roberts2,3, Ben K. Galton-Fenzi2,3, Duncan Young4, Donald Blankenship4, and Martin J. Siegert5 Felicity S. Graham et al.
  • 1Institute for Marine and Antarctic Studies, University of Tasmania, Private Bag 129, Hobart, Tasmania 7001, Australia
  • 2Australian Antarctic Division, Kingston, Tasmania, Australia
  • 3Antarctic Climate & Ecosystems Cooperative Research Centre, Private Bag 80, Hobart, Tasmania 7001, Australia
  • 4Institute for Geophysics, University of Texas at Austin, Austin, Texas 78758, USA
  • 5Grantham Institute and Department of Earth Sciences and Engineering, Imperial College London, London SW7 2AZ, UK

Abstract. Digital elevation models of Antarctic bed topography are smoothed and interpolated onto low-resolution ( > 1 km) grids as current observed topography data are generally sparsely and unevenly sampled. This issue has potential implications for numerical simulations of ice-sheet dynamics, especially in regions prone to instability where detailed knowledge of the topography, including fine-scale roughness, is required. Here, we present a high-resolution (100 m) synthetic bed elevation terrain for Antarctica, encompassing the continent, continental shelf, and seas south of 60° S. Although not identically matching observations, the synthetic bed surface – denoted as HRES – preserves topographic roughness characteristics of airborne and ground-based ice-penetrating radar data measured by the ICECAP (Investigating the Cryospheric Evolution of the Central Antarctic Plate) consortium or used to create the Bedmap1 compilation. Broad-scale ( > 5 km resolution) features of the Antarctic landscape are incorporated using a low-pass filter of the Bedmap2 bed elevation data. HRES has applicability in high-resolution ice-sheet modelling studies, including investigations of the interaction between topography, ice-sheet dynamics, and hydrology, where processes are highly sensitive to bed elevations and fine-scale roughness. The data are available for download from the Australian Antarctic Data Centre (doi:10.4225/15/57464ADE22F50).

Short summary
Antarctic bed topography datasets are interpolated onto low-resolution grids because our observed topography data are sparsely sampled. This has implications for ice-sheet model simulations, especially in regions prone to instability, such as grounding lines, where detailed knowledge of the topography is required. Here, we constructed a high-resolution synthetic bed elevation dataset using observed covariance properties to assess the dependence of simulated ice-sheet dynamics on grid resolution.