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TitrePSInSAR monitoring of ground movement at Salluit, Quebec (Canada), due to freeze-thaw cycles, active layer thickening, and permafrost warming
AuteurFortier, R; LeBlanc, A -M; Falorni, G; Therrien, R
SourceProceedings of the 10th International Permafrost Conference; par Fortier, R (éd.); 2012 p. 113-118
Séries alt.Secteur des sciences de la Terre, Contribution externe 20110263
RéunionInternational Permafrost Conference; Salekhard; RU; juin 25-29, 2012
Lat/Long OENS-76.0000 -75.5000 62.2500 62.0000
Sujetspergélisol; glace fossile; congélation du sol; températures au sol; méthodes radar; imagerie radar; mouvement de la glace; climat arctique; fluctuations climatiques; géologie de l'environnement; géologie des dépôts meubles/géomorphologie; Nature et environnement
Illustrationslocation maps; plots; tables
ProgrammeGestionaire de programme - sciences de changements climatiques, Géosciences de changements climatiques
Résumé(disponible en anglais seulement)
Radar images of Salluit in Northern Quebec, Canada, taken by the ERS-1 and ERS-2 satellites from 1992 to 2000 were analyzed using a permanent scatterer interferometric synthetic aperture radar (PSInSAR) technique to monitor ground movement. Time series of PS targets on rock outcrops show that postglacial uplift generates ground motion toward the satellite at velocities of about 1 mm/year. Other PS targets on ice-poor saline permafrost indicate ground motion away from the satellite at velocities in excess of 7 mm/year with superposed annual variations of 8 mm in amplitude. Numerical simulations of the impacts on the thermal regime of permafrost with an increase in air temperature of about 2°C, as observed in Northeastern Canada over the study period, suggest that the subsidence is due to the active layer thickening and permafrost warming while the annual variations are caused by the freeze-thaw cycles in the active layer.