Thermal and Mechanical Modeling of Coastal Erosion Processes on Tuktoyaktuk Island, Northwest Territories

Ouellette, Danika Sophie

Thermal and Mechanical Modeling of Coastal Erosion Processes on Tuktoyaktuk Island, Northwest Territories

dc.contributor.advisor	Hayley, Jocelyn H.
dc.contributor.advisor	Priest, Jeffrey A.
dc.contributor.author	Ouellette, Danika Sophie
dc.contributor.committeemember	Moorman, Brian J.
dc.contributor.committeemember	Zhou, Qi
dc.date	2021-11
dc.date.accessioned	2021-09-23T14:07:33Z
dc.date.available	2021-09-23T14:07:33Z
dc.date.issued	2021-09-16
dc.description.abstract	Arctic coasts are particularly vulnerable to rapid and extreme erosion due to the presence of ice-rich permafrost sediment, with erosion rates varying anywhere from 1 to 20 m/yr in the region. Erosion is limited to the open-water season such that the factors controlling rates of erosion are warmer air temperatures and storm surges impacting the sensitive ice-rich permafrost coastal bluffs. Erosional processes in the Arctic are unique and consist of coupled thermal and mechanical mechanisms. The coastal community of Tuktoyaktuk, Northwest Territories, located along the Beaufort Sea coast in the western Canadian Arctic, has been dealing with the consequences of coastal erosion for many decades and will likely face displacement due to accelerating rates of erosion. In this study, a process-based thermal-mechanical erosion numerical model was developed for Tuktoyaktuk Island, which currently shelters the harbour and eastern shores of the community from wave impact, to investigate erosional processes commonly impacting ice-rich permafrost coasts including thermal denudation of the cliff face, and thermal abrasion and formation of thermoerosional niche at the base of the cliff under a storm surge to understand the impact of permafrost sediment properties on rates of erosion. It was found that erosion rates vary significantly between stratigraphic units, where sandy silt sediments have higher rates than ice rich clayey silt layers due to latent heat effects, and therefore should be considered on a site-specific scale for engineering purposes rather than the traditional cliff edge retreat method. The increased granularity improved our understanding of erosion rates on Tuktoyaktuk Island thus enabling future detailed consideration of mitigation strategies. It was concluded that massive block failure due to the formation of a thermoerosional niche under a storm surge is presently unlikely to occur on the island. For block failure to occur, either a storm of extreme duration or storm surge level is required. Lastly, it is expected that erosion rates will increase under climate-driven change such that the drivers of accelerated erosion are relative sea level rise, decrease in sea ice extent, and increase in surface air temperatures.	en_US
dc.identifier.citation	Ouellette, D. S. (2021). Thermal and Mechanical Modeling of Coastal Erosion Processes on Tuktoyaktuk Island, Northwest Territories (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.	en_US
dc.identifier.doi	http://dx.doi.org/10.11575/PRISM/39266
dc.identifier.uri	http://hdl.handle.net/1880/113949
dc.language.iso	eng	en_US
dc.publisher.faculty	Schulich School of Engineering	en_US
dc.publisher.institution	University of Calgary	en
dc.rights	University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.	en_US
dc.subject	Arctic	en_US
dc.subject	Permafrost	en_US
dc.subject	Coastal Erosion	en_US
dc.subject	Numerical Modeling	en_US
dc.subject.classification	Engineering--Environmental	en_US
dc.subject.classification	Engineering--Marine and Ocean	en_US
dc.subject.classification	Geotechnology	en_US
dc.title	Thermal and Mechanical Modeling of Coastal Erosion Processes on Tuktoyaktuk Island, Northwest Territories	en_US
dc.type	master thesis	en_US
thesis.degree.discipline	Engineering – Civil	en_US
thesis.degree.grantor	University of Calgary	en_US
thesis.degree.name	Master of Science (MSc)	en_US
ucalgary.item.requestcopy	true	en_US