Letter abstract


Nature Geoscience 3, 92 - 95 (2010)
Published online: 17 January 2010 | Corrected online: 22 January 2010 | doi:10.1038/ngeo737

Subject Categories: Climate science | Cryospheric science

Contribution of Alaskan glaciers to sea-level rise derived from satellite imagery

E. Berthier1,2, E. Schiefer3, G. K. C. Clarke4, B. Menounos5 & F. Rémy1,2

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Over the past 50 years, retreating glaciers and ice caps contributed 0.5mmyr−1 to sea-level rise1, and one third of this contribution is believed to come from ice masses bordering the Gulf of Alaska2, 3. However, these estimates of ice loss in Alaska are based on measurements of a limited number of glaciers that are extrapolated to constrain ice wastage in the many thousands of others. Uncertainties in these estimates arise, for example, from the complex pattern of decadal elevation changes at the scale of individual glaciers and mountain ranges4, 5, 6, 7. Here we combine a comprehensive glacier inventory with elevation changes derived from sequential digital elevation models. We find that between 1962 and 2006, Alaskan glaciers lost 41.9±8.6km3yr−1 of water, and contributed 0.12±0.02mm yr−1 to sea-level rise, 34% less than estimated earlier2, 3. Reasons for our lower values include the higher spatial resolution of our glacier inventory as well as the reduction of ice thinning underneath debris and at the glacier margins, which were not resolved in earlier work. We suggest that estimates of mass loss from glaciers and ice caps in other mountain regions could be subject to similar revisions.

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  1. CNRS, LEGOS, 14 Av. Ed. Belin, F-31400 Toulouse, France
  2. Université de Toulouse, UPS (OMP-PCA), LEGOS, 14 Av. Ed. Belin, F-31400 Toulouse, France
  3. Department of Geography, Planning and Recreation, Northern Arizona University, Box 15016 Flagstaff, Arizona 86011-5016, USA
  4. Department of Earth and Ocean Sciences, University of British Columbia, 6339 Stores Road, Vancouver, British Columbia, V6T 1Z4, Canada
  5. Geography Program and Natural Resources Environmental Studies Institute, University of Northern British Columbia, Prince George, British Columbia, V2N 4Z9, Canada

Correspondence to: E. Berthier1,2 e-mail: etienne.berthier@legos.obs-mip.fr

* In the version of this Letter initially published online, the contribution to sea-level rise should have read 0.12±0.02mm yr−1. This error has been corrected in all versions of the text.