GEOSCAN, résultats de la recherche


TitreHydrological implications of periglacial expansion in the Peyto Glacier catchment, Canadian Rockies
AuteurHopkinson, C; Demuth, M N; Sitar, M
SourceProceedings of the Remote Sensing and Hydrology 2010 Symposium; 2010 p. 1-4
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110105
RéunionRemote Sensing and Hydrology 2010 Symposium; Jackson Hole, Wyoming; US; Septembre 27-30, 2010
Lat/Long OENS-117.0000 -116.5000 51.7500 51.5000
Sujetsmilieu hydrologique; glaciers; levés glaciaires; télédétection; glaciologie; hydrogéologie; géophysique; géologie des dépôts meubles/géomorphologie
Illustrationslocation maps; plots
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)
Multi-temporal photogrammetric and LiDAR-based DEMs collected over the Peyto Glacier (1949, 1966, 1993, 2000, 2010) were analysed to quantify rates of glacial and periglacial volumetric change. During this time, exposed glacier ice area has reduced by 18% from 14.2 to 11.6 km2, while the actively downwasting lateral moraine area has increased by 70% from 0.53 to 0.90 km2. This opposite trend results in an exponential increase in the periglacial areal proportion of actively downwasting surfaces. Mean annual volumetric loss from the glacier surface has been 14 × 106 m3, with active moraine downwasting accounting for a further 0.6 × 106 m3 (4.5%). Moraine volumetric losses from 2000 to 2010 were >6%, with an additional >2% in small hanging glacier and perennial snow patch areas. These results indicate that while Peyto Glacier is undergoing continuous retreat, runoff from periglacial areas ignored in the mass balance record account for up to 8% of contemporary losses from basin storage. LiDAR data were essential to this analysis, as accurate stratification of glacial and periglacial volumetric changes are not normally feasible using traditional field and photogrammetric mass balance techniques.