Seasonal and Multi-year Variability of Ice Dynamics of South Croker Bay Glacier, Devon Ice Cap, Canadian Arctic from 2015 to 2021
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Date
2023-01-20
Authors
Nikolic, Natalija
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Publisher
University of Waterloo
Abstract
The effects of climate change have already been observed across the globe, impacting weather, ecosystems, and society. These effects have been most pronounced in polar regions, which experience warming at a faster rate than other latitudes due to positive feedbacks resulting from reduced ice and snow cover. Compared to the 1.1oC of warming around the globe since the 1980s, the Arctic has warmed by 3oC. Glaciers and ice caps are of particular concern as they have profound impacts on water resources, shipping and travel routes, and global sea level rise. As such, glacier dynamics play a key role in understanding effects on the global system. The Canadian High Arctic in particular has doubled in rates of mass loss since the 1990s, which is of great concern as it is the third largest contributor to global sea level rise after Antarctica and Greenland. While glacier flow within the region has been studied, some glaciers have been observed to not align with current understandings of dynamics. The subject of this study, South Croker Bay Glacier, located on Devon Ice Cap in Nunavut, Canada has exhibited velocity variability on oscillating temporal scales which do not align with surging, pulsing, or consistent acceleration explanations. The primary objective of this thesis was to create a dense record of velocities derived from TerraSAR-X imagery every 11 days from 2015 to 2021 to gain insight into seasonal and multi-annual velocity variability. As a result, a near-continuous velocity record of South Croker Bay Glacier has been created, highlighting a shift in velocities which occurred during the winter of 2018/19. The second objective was to explore the potential drivers of the observed velocity variability, which were hydrology, sea ice buttressing, and bed topography. Looking at the spatial propagation of acceleration and terminus position as well, it is concluded that the variability is not driven by surge- or pulse-type mechanisms. Instead, it is suggested that the driver of the observed variability on the glacier is the result of the evolving configuration of the hydrological network. This is supported by surface air temperature and surface lake area records during the study period. Finally, the third objective was to assess the feasibility of utilizing remote sensing for seasonal variability detection. Based on the analysis, the method was successful in the proposed objectives, creating a record of velocities that was not previously available for South Croker Bay Glacier.
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Keywords
ice dynamics, glacier dynamics, seasonality, Canadian Arctic, Devon Ice Cap, South Croker Bay