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TitleSeven decades of uninterrupted advance of Good Friday Glacier, Axel Heiberg Island, Arctic Canada
AuthorMedrzycka, D; Copland, L; Van Wychen, W; Burgess, D
SourceJournal of Glaciology vol. 65, issue 251, 2019 p. 440-452, (Open Access)
Alt SeriesNatural Resources Canada, Contribution Series 20190120
PublisherCambridge University Press (CUP)
Mediapaper; on-line; digital
File formatpdf (Adobe® Reader®); html
NTS59E/03; 59E/04; 59E/05; 59E/06; 59E/11; 59E/12; 59E/13; 59E/14; 59F/01; 59F/08; 59F/09; 59F/16
AreaGood Friday Glacier; Axel Heiberg Island; Canadian Arctic Archipelago
Lat/Long WENS -92.5000 -90.0000 79.0000 78.0000
Subjectssurficial geology/geomorphology; hydrogeology; environmental geology; Nature and Environment; glaciology; glaciers; ice flow; flow rates; flow velocities; glacial surges; ice movement; discharge rates; remote sensing; satellite imagery; photogrammetric techniques; airphoto interpretation; bedrock topography; climate; Little Ice Age; synthetic aperture radar applications; mass balance; glacier geometry; ice dynamics; Landsat 8; glacier terminus; climate change
Illustrationslocation maps; satellite images; tables; geoscientific sketch maps; aerial photographs; photographs; profiles
ProgramGSC Atlantic Division, Glacier Mass Balance Project
ProgramPolar Continental Shelf Program
Released2019 05 14
AbstractPrevious studies reported that Good Friday Glacier had been actively surging in the 1950-60s, 1990s and again in 2000-15. Based on observations of terminus position change from air photos and satellite imagery, we fill the gaps between previous studies and conclude that the glacier has been advancing continuously since 1959. Ice surface velocities extracted from optical and synthetic aperture radar satellite images show higher flow rates than on most other marine-terminating glaciers in the region. This behaviour contrasts with the regional trend of glacier retreat over this period. Possible explanations involve a delayed response to positive mass-balance conditions of the Little Ice Age, or a dynamic instability. There is, however, insufficient evidence to attribute this behaviour to classical glacier surging as suggested in previous studies. Based on present-day ice velocity and glacier geometry patterns in the terminus region, we reconstruct the evolution of ice motion throughout the advance, and suggest that what has previously been interpreted as a surge, may instead have been a localised response to small-scale perturbations in bedrock topography.
Summary(Plain Language Summary, not published)
The rate of mass loss due to ice berg calving can represent a significant form of ablation from a land-based glacier system, and can pose a hazard to offshore infrastructure and marine transportation vessels. In this study, we analyse the factors controlling flow of a large tidewater glacier that drains into the Arctic Ocean from Axel Heiberg Island. Our results indicate that intermittent speed-up events have been caused through release of pressure built up at bedrock point of high friction, rather than cyclical surging as has been suggested by previous studies. Knowledge of the factors controlling flow rate of tidewater terminating glaciers provide an increased understanding as to the potential rate of ice berg calving production to oceans in the future.