Title | Seasonal and multiyear flow variability on the Prince of Wales Icefield, Ellesmere Island: 2009-2019 |
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Author | Dalton, A; Van Wychen, W; Copland, L; Gray, L; Burgess, D |
Source | Journal of Geophysical Research e2021JF006501, 2022 p. 1-20, https://doi.org/10.1029/2021JF006501 |
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Year | 2022 |
Alt Series | Natural Resources Canada, Contribution Series 20220007 |
Publisher | American Geophysical Union |
Document | serial |
Lang. | English |
Media | paper; on-line; digital |
File format | pdf; html |
Province | Nunavut |
Area | Prince of Wales Icefield; Ellesmere Island; Trinity Glacier; Wykeham Glacier; Ekblaw Glacier; Cadogan Glacier |
Lat/Long WENS | -81.0000 -76.0000 80.0000 77.0000 |
Subjects | surficial geology/geomorphology; hydrogeology; environmental geology; geophysics; Science and Technology; Nature and Environment; glaciers; ice flow; flow rates; ice thicknesses; climate effects;
climate, arctic; remote sensing; satellite imagery; radar methods; topography; Radarsat-2; Climate change |
Illustrations | location maps; satellite images; time series; profiles; geoscientific sketch maps; cross-sections |
Program | Climate Change Geoscience Glacier Mass Balance Project |
Released | 2022 03 23 |
Abstract | Over the last two decades, Trinity, Wykeham, Ekblaw, and Cadogan glaciers have retreated and been identified as the primary sources of iceberg flux from Prince of Wales (POW) Icefield, Ellesmere Island,
accounting for ~83% of total solid ice discharge. In this study, we used a total of 167 Radarsat-2 Synthetic Aperture Radar scene pairs collected between 2009 and 2019 to derive winter surface velocities of these four major basins of the POW
Icefield. Over this period both Cadogan and Ekblaw glaciers underwent multiyear acceleration and deceleration limited to their lower parts, consistent with characteristics of 'pulse-type' glaciers. Trinity and Wykeham glaciers are currently the
fastest flowing glaciers in the CAA and are grounded below sea level for ~40 km up-glacier from their termini. Both glaciers underwent multiyear repeating periods of velocity acceleration between 2009 and 2019 which coincided with significant
thinning at their termini. As of 2017, Trinity and Wykeham were each within ~10 m of flotation over their lowermost 4 km. We also identified a shift in flow since 2014 on Trinity and Wykeham, after which winter flow rates began to propagate
up-glacier and were nearly identical to flow rates observed throughout the rest of the year, indicating that seasonal variability in flow has become less apparent in recent years. Our findings suggest that Trinity and Wykeham glaciers have
transitioned to a flow type dominated by dynamic thinning, which is strongly influenced by subglacial topography and may be susceptible to instability of the glacier front and large-scale collapse. |
Summary | (Plain Language Summary, not published) Arctic Canada hosts over 200 tidewater terminating glaciers that discharge large chunks of ice, or ice bergs, directly into the ocean. Ice berg calving
can be significant for certain ice caps or glacier basins, and the bergs discharged can pose a significant threat to marine infrastructure and ships. In this study we analyse multiple remote sensing acquired between 2009 and 2019 to measure of ice
motion of the major tidewater glaciers that drain the Prince of Wales ice field, Arctic Canada. Our results show significant acceleration over this 10-year period of time, and concurrent thinning and retreat of these glacier termini. In addition,
analysis of the ice thickness data indicate that the Trinity and Wykham glaciers, the largest of the ensemble of glacier analysed in this study, are nearing floatation. This trend indicates that the termini region of these glacier termini may be in
the process of destabilization and are likely to experience further speed-up and collapse. Results from this study are consistent with other observations of enhanced shrinkage and retreat of glaciers and ice caps across Canada's high
Arctic. |
GEOSCAN ID | 329939 |
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