Earth System Science Data www.earth-syst-sci-data.net 1866-3508 1866-3516 2 2 2010 10.5194/essd-2-261-2010 http://www.earth-syst-sci-data.net/2/261/2010/ http://www.earth-syst-sci-data.net/2/261/2010/essd-2-261-2010.html http://www.earth-syst-sci-data.net/2/261/2010/essd-2-261-2010.pdf 261 273 2010-12-22 A consistent data set of Antarctic ice sheet topography, cavity geometry, and global bathymetry R. Timmermann ralph.timmermann@awi.de A. Le Brocq T. Deen E. Domack P. Dutrieux B. Galton-Fenzi H. Hellmer A. Humbert D. Jansen A. Jenkins A. Lambrecht K. Makinson F. Niederjasper F. Nitsche O. A. Nøst L. H. Smedsrud W. H. F. Smith Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany University of Exeter, Exter, UK British Antarctic Survey, Cambridge, UK Hamilton College, Clinton, NY, USA University of Tasmania, Hobart, Tasmania KlimaCampus, University of Hamburg, Hamburg, Germany Swansea University, Swansea, UK University Innsbruck, Innsbruck, Austria Lamont-Doherty Earth Observatory, Columbia University, Palisades, NY, USA Norwegian Polar Institute, Tromsø, Norway Bjerknes Centre for Climate Research, Bergen, Norway Laboratory for Satellite Altimetry, NOAA NESDIS, Silver Spring, MD, USA Sub-ice shelf circulation and freezing/melting rates in ocean general circulation models depend critically on an accurate and consistent representation of cavity geometry. Existing global or pan-Antarctic topography data sets have turned out to contain various inconsistencies and inaccuracies. The goal of this work is to compile independent regional surveys and maps into a global data set. We use the S-2004 global 1-min bathymetry as the backbone and add an improved version of the BEDMAP topography (ALBMAP bedrock topography) for an area that roughly coincides with the Antarctic continental shelf. The position of the merging line is individually chosen in different sectors in order to capture the best of both data sets. High-resolution gridded data for ice shelf topography and cavity geometry of the Amery, Fimbul, Filchner-Ronne, Larsen C and George VI Ice Shelves, and for Pine Island Glacier are carefully merged into the ambient ice and ocean topographies. Multibeam survey data for bathymetry in the former Larsen B cavity and the southeastern Bellingshausen Sea have been obtained from the data centers of Alfred Wegener Institute (AWI), British Antarctic Survey (BAS) and Lamont-Doherty Earth Observatory (LDEO), gridded, and blended into the existing bathymetry map. 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