| Title | Seven decades of uninterrupted advance of Good Friday Glacier, Axel Heiberg Island, Arctic Canada |
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| Author | Medrzycka, D; Copland, L; Van Wychen, W; Burgess, D |
| Source | Journal of Glaciology vol. 65, issue 251, 2019 p. 440-452, https://doi.org/10.1017/jog.2019.21  Open Access |
| Image |  |
| Year | 2019 |
| Alt Series | Natural Resources Canada, Contribution Series 20190120 |
| Publisher | Cambridge University Press (CUP) |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf (Adobe® Reader®); html |
| Province | Nunavut |
| NTS | 59E/03; 59E/04; 59E/05; 59E/06; 59E/11; 59E/12; 59E/13; 59E/14; 59F/01; 59F/08; 59F/09; 59F/16 |
| Area | Good Friday Glacier; Axel Heiberg Island; Canadian Arctic Archipelago |
| Lat/Long WENS | -92.5000 -90.0000 79.0000 78.0000 |
| Subjects | surficial 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; Climate change |
| Illustrations | location maps; satellite images; tables; geoscientific sketch maps; aerial photographs; photographs; profiles |
| Program | GSC Atlantic Division Glacier Mass Balance Project |
| Program | Polar Continental Shelf Program
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| Released | 2019 05 14 |
| Abstract | Previous 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. |
| GEOSCAN ID | 314788 |
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