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TitreRecent volume and mass changes of Penny Ice Cap (Baffin Island, Nunavut) determined using repeat airborne laser altimetry
AuteurSchaffer, N; Zdanowicz, C; Copland, L; Burgess, D O
SourceAmerican Geophysical Union, Fall Meeting 2011, abstracts; 2011AGUFM.C13A0722S, 2011 p. 1 (Accès ouvert)
LiensOnline - En ligne
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110336
RéunionAmerican Geophysical Union, Fall Meeting 2011; San Francisco, CA; US; décembre 5-9, 2011
Documentsite Web
Mediaen ligne; numérique
Formatshtml; pdf
SujetsNature et environnement
ProgrammeGéosciences de changements climatiques, Les sciences de la Terre à l'appui de la caractérisation, à l'échelle nationale, des impacts des changements climatiques sur la masse continentale canadienne
Diffusé2011 12 01
Résumé(disponible en anglais seulement)
Recent observations of accelerated glacier wastage in Greenland and Alaska have prompted reassessments of mass balance trends and volume changes on Canadian Arctic glaciers and ice caps. While long surface mass balance measurements are available from ice caps of the Queen Elizabeth Islands (e.g., Axel Heiberg and Devon islands), no such records exist for Baffin Island glaciers. In the absence of such data, air- and space-borne measurements can be used in combination with ice core data and in-situ ground penetrating radar surveys to evaluate historical and recent trends in ice cover changes. Here, we use repeat laser airborne altimetry surveys conducted in 2000 and 2005 to estimate current volume and mass reduction rates of Penny Ice Cap, the southernmost large ice cap on Baffin Island (~66°N). This work builds on previous surveys for the period 1995-2000 [Abdalati et al. (2004) JGR 109: F04007.] Surface elevation changes along altimetry lines are extrapolated to the entire ice cap using a digital elevation model (DEM). Changes in areal extent of the ice cap are constrained using satellite imagery (e.g. Landsat). From these data and using firn density profiles measured in cores, we estimate the total mass wastage of the ice cap and its contribution to sea level rise.