TC The Cryosphere TC The Cryosphere 1994-0424 Copernicus Publications Göttingen, Germany 10.5194/tc-7-375-2013 Bedmap2: improved ice bed, surface and thickness datasets for Antarctica Fretwell P. 36 1 Pritchard H. D. https://orcid.org/0000-0003-2936-1734 36 1 Vaughan D. G. 1 Bamber J. L. https://orcid.org/0000-0002-2280-2819 2 Barrand N. E. https://orcid.org/0000-0003-4428-1863 1 Bell R. 3 Bianchi C. 4 Bingham R. G. https://orcid.org/0000-0002-0630-2021 5 Blankenship D. D. 6 Casassa G. 7 Catania G. 6 Callens D. https://orcid.org/0000-0001-9921-0910 8 Conway H. https://orcid.org/0000-0003-4634-3474 9 Cook A. J. 10 Corr H. F. J. 1 Damaske D. 11 Damm V. 11 Ferraccioli F. 1 Forsberg R. 12 Fujita S. https://orcid.org/0000-0003-0127-0777 13 Gim Y. 14 Gogineni P. 15 Griggs J. A. 2 Hindmarsh R. C. A. https://orcid.org/0000-0003-1633-2416 1 Holmlund P. 16 Holt J. W. 6 Jacobel R. W. https://orcid.org/0000-0002-6898-7521 17 Jenkins A. 1 Jokat W. 18 Jordan T. 1 King E. C. https://orcid.org/0000-0003-3793-3915 1 Kohler J. 19 Krabill W. 20 Riger-Kusk M. 21 Langley K. A. 22 Leitchenkov G. 23 Leuschen C. 15 Luyendyk B. P. 24 Matsuoka K. https://orcid.org/0000-0002-3587-3405 25 Mouginot J. 26 Nitsche F. O. 3 Nogi Y. 27 Nost O. A. 25 Popov S. V. 28 Rignot E. 29 Rippin D. M. https://orcid.org/0000-0001-7757-9880 30 Rivera A. https://orcid.org/0000-0002-2779-4192 7 Roberts J. https://orcid.org/0000-0002-3477-4069 31 Ross N. https://orcid.org/0000-0002-8338-4905 32 Siegert M. J. https://orcid.org/0000-0002-0090-4806 2 Smith A. M. https://orcid.org/0000-0001-8577-482X 1 Steinhage D. 18 Studinger M. 33 Sun B. 34 Tinto B. K. 3 Welch B. C. 18 Wilson D. 35 Young D. A. 6 Xiangbin C. 34 Zirizzotti A. 4 British Antarctic Survey, Cambridge, UK School of Geographical Sciences, University of Bristol, UK Lamont-Doherty Earth Observatory of Columbia University, Palisades, USA Istituto Nazionale di Geofisica e Vulcanologia, Rome, Italy School of Geosciences, University of Aberdeen, UK Institute for Geophysics, University of Texas at Austin, USA Centro de Estudios Cientificos, Santiago, Chile Laboratoire de Glaciologie, Université Libre de Bruxelles, Brussels, Belgium Earth and Space Sciences, University of Washington, Seattle, USA Department of Geography, Swansea University, Swansea, UK Federal Institute for Geosciences and Natural Resources, Hannover, Germany National Space Institute, Technical University of Denmark, Denmark National Institute of Polar Research, Tokyo, Japan Jet Propulsion Laboratory. California Institute of Technology, Pasadena, USA Electrical Engineering & Computer Science, University of Kansas, Lawrence, USA Stockholm University, Stockholm, Sweden St. Olaf College, Northfield, MN 55057, USA Alfred Wegener Institute, Bremerhaven, Germany Norwegian Polar Institute, Fram Centre, Tromsø, Norway NASA Wallops Flight Facility, Virginia, USA College of Science, University of Canterbury, Christchurch, New Zealand Department of Geosciences, University of Oslo, Norway Institute for Geology and Mineral Resources of the World Ocean, St.-Petersburg, Russia Earth Research Institute, University of California in Santa Barbara, USA Norwegian Polar Institute, Tromso, Norway Department of Earth System Science, University of California, Irvine, USA National Institute of Polar Research, Tokyo, Japan Polar Marine Geosurvey Expedition, St.-Petersburg, Russia School of Physical Sciences, University of California, Irvine, USA Environment Department, University of York, Heslington, York, YO10 5DD, UK Department of Sustainability, Environment, Water, Population and Communities, Australian Antarctic Division, Hobart, Tasmania, Australia School of Geography, Politics and Sociology, Newcastle University, Newcastle upon Tyne, NE1 7RU, UK NASA Goddard Space Flight Center, Greenbelt, USA Polar Research Institute of China, Shanghai, China Instituite for Crustal Studies, University of California in Santa Barbara, USA These authors contributed equally to this work. 28 02 2013 7 1 375 393 Copyright: © 2013 P. Fretwell et al. 2013 This work is licensed under the Creative Commons Attribution 3.0 Unported License. To view a copy of this licence, visit https://creativecommons.org/licenses/by/3.0/ This article is available from https://tc.copernicus.org/articles/7/375/2013/tc-7-375-2013.html The full text article is available as a PDF file from https://tc.copernicus.org/articles/7/375/2013/tc-7-375-2013.pdf

We present Bedmap2, a new suite of gridded products describing surface elevation, ice-thickness and the seafloor and subglacial bed elevation of the Antarctic south of 60° S. We derived these products using data from a variety of sources, including many substantial surveys completed since the original Bedmap compilation (Bedmap1) in 2001. In particular, the Bedmap2 ice thickness grid is made from 25 million measurements, over two orders of magnitude more than were used in Bedmap1. In most parts of Antarctica the subglacial landscape is visible in much greater detail than was previously available and the improved data-coverage has in many areas revealed the full scale of mountain ranges, valleys, basins and troughs, only fragments of which were previously indicated in local surveys. The derived statistics for Bedmap2 show that the volume of ice contained in the Antarctic ice sheet (27 million km<sup>3</sup>) and its potential contribution to sea-level rise (58 m) are similar to those of Bedmap1, but the mean thickness of the ice sheet is 4.6% greater, the mean depth of the bed beneath the grounded ice sheet is 72 m lower and the area of ice sheet grounded on bed below sea level is increased by 10%. The Bedmap2 compilation highlights several areas beneath the ice sheet where the bed elevation is substantially lower than the deepest bed indicated by Bedmap1. These products, along with grids of data coverage and uncertainty, provide new opportunities for detailed modelling of the past and future evolution of the Antarctic ice sheets.

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