Modelling intra-annual dynamics of a major marine-terminating Arctic glacier
Autor: | Sam Pimentel, Gwenn E. Flowers, Martin J. Sharp, Bradley Danielson, Luke Copland, Wesley Van Wychen, Angus Duncan, Jeffrey L. Kavanaugh |
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Jazyk: | angličtina |
Rok vydání: | 2017 |
Předmět: | |
Zdroj: | Annals of Glaciology, Vol 58, Pp 118-130 (2017) |
Druh dokumentu: | article |
ISSN: | 0260-3055 1727-5644 |
DOI: | 10.1017/aog.2017.23 |
Popis: | Significant intra-annual variability in flow rates of tidewater-terminating Arctic glaciers has been observed in recent years. These changes may result from oceanic and/or atmospheric forcing through (1) perturbations at the terminus, such as enhanced submarine melt and changes in sea-ice buttressing, or (2) increased surface melt, in response to atmospheric warming, reaching the bed and promoting glacier slip. We examine the influence of these processes on Belcher Glacier, a large fast-flowing tidewater outlet of the Devon Island ice cap in the Canadian Arctic. A hydrologically-coupled higher-order ice flow model is used to estimate changes in glacier flow speed as a result of changes in sea-ice buttressing and hydrologically-driven melt-season dynamics. Daily run-off from five sub-catchments over the 2008 and 2009 melt seasons provides meltwater forcing for the model simulations. Model results are compared with remotely-sensed and in situ ice-surface velocity measurements. Sea-ice effects are found to have a minor influence on glacier flow speed relative to that of meltwater drainage, which is clearly implicated in short-term velocity variations during the melt season. We find that threshold drainage is essential in determining the timing of these short-lived accelerations. |
Databáze: | Directory of Open Access Journals |
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