TC The Cryosphere TC The Cryosphere 1994-0424 Copernicus Publications Göttingen, Germany 10.5194/tc-6-763-2012 Significant contribution to total mass from very small glaciers Bahr D. B. 2 1 Radić V. 3 Institute of Arctic and Alpine Research, UCB 450, University of Colorado at Boulder, Boulder, CO, USA Department of Physics and Computational Science, Regis University, Denver, CO, USA Department of Earth and Ocean Sciences, University of British Columbia, Vancouver, Canada 12 07 2012 6 4 763 770 Copyright: © 2012 D. B. Bahr 2012 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/6/763/2012/tc-6-763-2012.html The full text article is available as a PDF file from https://tc.copernicus.org/articles/6/763/2012/tc-6-763-2012.pdf

A single large glacier can contain tens of millions of times the mass of a small glacier. Nevertheless, very small glaciers (with area &le;1 km<sup>2</sup>) are so numerous that their contribution to the world's total ice volume is significant and may be a notable source of error if excluded. With current glacier inventories, total global volume errors on the order of 10% are possible. However, to reduce errors to below 1% requires the inclusion of glaciers that are smaller than those recorded in most inventories. At the global scale, 1% accuracy requires a list of all glaciers and ice caps (GIC, exclusive of the ice sheets) larger than 1 km<sup>2</sup>, and for regional estimates requires a complete list of all glaciers down to the smallest possible size. For this reason, sea-level rise estimates and other total mass and total volume analyses should not omit the world's smallest glaciers. In particular, upscaling GIC inventories has been common practice in sea level estimates, but downscaling may also be necessary to include the smallest glaciers.

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