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TitreSharply increased mass loss from glaciers and ice caps in the Canadian Arctic Archipelago
AuteurGardner, A S; Moholdt, G; Wouters, B; Wolken, G J; Burgess, D O; Sharp, M J; Cogley, J G; Braun, C; Labine, C
SourceNature (London) vol. 473, issue 7347, 2011 p. 357-360,
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110161
Documentpublication en série
Mediapapier; en ligne; numérique
SNRC25; 26; 27; 37; 38; 48; 39; 49; 58; 59; 120; 340; 560
Lat/Long OENS-102.0000 -60.0000 84.0000 61.5000
Sujetsvariations du niveau de la mer; changements du niveau de la mer; glaciers; glace; climat arctique; fluctuations climatiques; géologie de l'environnement; Quaternaire
Illustrationslocation maps
ProgrammeLes sciences de la Terre à l'appui de la caractérisation, à l'échelle nationale, des impacts des changements climatiques sur la masse continentale canadienne, Géosciences de changements climatiques
Résumé(disponible en anglais seulement)
Mountain glaciers and ice caps are contributing significantly to present rates of sea level rise and will continue to do so over the next century and beyond. The Canadian Arctic Archipelago, located off the northwestern shore of Greenland, contains one-third of the global volume of land ice outside the ice sheets, but its contribution to sea-level change remains largely unknown. Here we show that the Canadian Arctic Archipelago has recently lost 61±7 gigatonnes per year (Gt yr-1) of ice, contributing 0.17 ± 0.02 mm yr-1 to sea-level rise. Our estimates are of regional mass changes for the ice caps and glaciers of the Canadian Arctic Archipelago referring to the years 2004 to 2009 and are based on three independent approaches: surface mass-budget modelling plus an estimate of ice discharge (SMB+D), repeat satellite laser altimetry (ICESat) and repeat satellite gravimetry (GRACE). All three approaches show consistent and large mass-loss estimates. Between the periods 2004--2006 and 2007--2009, the rate of mass loss sharply increased from 31±8 Gt yr-1 to 92±12 Gt yr-1 in direct response to warmer summer temperatures, to which rates of ice loss are highly sensitive (64±14 Gt yr-1 per 1K increase). The duration of the study is too short to establish a longterm trend, but for 2007--2009, the increase in the rate of mass loss makes the Canadian Arctic Archipelago the single largest contributor to eustatic sea-level rise outside Greenland and Antarctica.