Natalie Arpin will be presenting Understanding Frost Jacking Effects on Transportation Infrastructure in Permafrost Regions: Insights from the Hudson Bay Railway.
Date: 29 January 2025 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
The Hudson Bay Railway plays a crucial role in Canada by providing an all-season, land-based pathway to transport goods to Northern communities, but the diverse ground conditions, ranging from isolated to continuous permafrost, create significant obstacles in maintaining its operation. The presentation will discuss current efforts to improve understanding of how ground conditions affect railway bridges, with a specific focus on frost jacking.
Allison Plourde will be presenting Measuring Active Layer Dynamics with InSAR.
Date: 18 December 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
InSAR (Interferometric Synthetic Aperture Radar) is a well-established method for measuring small-scale surface deformations across vast regions. However, the influence of snow cover on InSAR phase limits the comprehensive tracking of seasonal dynamics in permafrost terrain. This study focuses on low-land permafrost near Inuvik, Northwest Territories, aiming to enhance understanding of permafrost active layer dynamics, particularly in winter. To tackle this, a multifaceted approach combining C-band and X-band InSAR measurements with in-situ data has been developed. Instrumentation at research sites includes inclinometers for vertical surface deformation, ultrasonic range finders for snow depth, and corner reflectors as InSAR references. This comprehensive approach aims to contribute valuable insights to the scientific understanding of permafrost monitoring techniques and addresses the impact of snow cover on InSAR measurements in permafrost terrain.
Zakieh Mohammadi will be presenting A framework for evaluating thaw settlement.
Date: 4 December 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Thaw settlement is a common challenge for infrastructure built on permafrost, leading to higher maintenance costs and reduced service life. This seminar will discuss the development of essential components for a comprehensive framework aimed at evaluating thaw settlement in permafrost regions—an important resource for northern infrastructure planning. Key highlights include a new qualitative approach for assessing thaw settlement potential using regional and national ground ice maps and inferred soil textures from geological data. A compiled dataset of thaw settlement test results, which has helped address gaps in thaw strain estimation resources, will be presented. This dataset enabled the development of new predictive tools, including methods for estimating thaw strain in coarse-grained sediments based on particle size distribution and for highly organic soils based on water content. Additionally, relying on this dataset, the seminar will cover comparative analyses of thaw settlement properties across different soil types and evaluations of existing thaw strain prediction tools. The newly developed tools and approaches, along with the insights gained, will inform the creation of the final framework, contributing to designing resilient infrastructure in permafrost regions.
Rose Lefebvre will be presenting Modelling the nitrogen cycle of mosses across the boreal forest.
Date: 13 November 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Mosses are common ground cover species in the boreal forest. They can influence different components of the ecosystem, such as the ground thermal regime due to their insulating properties, and the nitrogen cycle through biological nitrogen fixation. Mosses are not always included in terrestrial biosphere models, which are used to make climate projections. The Canadian Land Surface Scheme Including Biogeochemical Cycles (CLASSIC) was modified with the goal of improving productivity simulations across the North American boreal forest. Feather mosses and the nitrogen cycle of mosses were implemented in CLASSIC. The model was validated by comparing observation data against model output at eight sites. The sites range from being near the southern limit of permafrost to being in the continuous permafrost zone. Once validated, the model was run across the North American boreal forest.
Rae Landriau will be presenting Performance of Drilling Waste Sumps, Western Arctic Canada.
Date: 16 October 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Petroleum resource exploration and development has occurred in the Northwest Territories since the 1920s. Freezing-point depressants, mainly potassium chloride, were added to drilling fluids to facilitate drilling into permafrost. Disposal of these fluids was typically in large man-made pits (sumps). Sumps were excavated in permafrost, with the intention that frozen ground would contain the fluids indefinitely. Climatic warming in northwest Canada has raised the temperature of near-surface permafrost, increasing the potential for failure of sumps in the region. Using electro-magnetic surveys, ground conductivity on and off sumps can be collected and analyzed to detect the presence of these fluids and determine if they have migrated.
Hannah Macdonell will be presenting Development and demonstration of a statistical ranking framework for ground temperature models, tailored towards permafrost environments.
Date: 18 September 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Models used to simulate permafrost variables such as ground temperature are important tools for understanding the current state and future conditions of permafrost. However, few objective methods of establishing model accuracy exist for permafrost environments. Additionally, models often range in their performance given different conditions such as terrain type or seasonality. Hannah will be presenting her master’s research that looked at (1) identifying patterns in ground-temperature model performance under different testing conditions and (2) developing a quantitative measure of ground-temperature model performance in permafrost zones.
Tabatha Rahman presented Ice-Wedge Volume, Distribution, and Development in the Barrens of the Hudson Bay Lowlands, Northern Manitoba.
Extensive ice-wedge polygon networks are found in the ‘Barrens’ of northern Manitoba, a 50,000 km2 zone of continuous permafrost tundra that emerged from the Tyrrell Sea less than 5,500 years ago. Tabatha will present empirical results of ice-wedge volume and tri-dimensional distribution, and will focus on the environmental conditions associated with the growth and degradation of ice wedges in this uplifted permafrost peatland. Knowledge of wedge-ice morphology and development is essential for the prediction and mitigation of risks associated with anticipated permafrost thaw in the Barrens.
Usman Iqbal Ahmed will be presenting Precise Change Detection with Airborne Interferometric Synthetic Aperture Radar (InSAR) & Optical Photogrammetry Data and its application to Active Permafrost Regions.
Permafrost thaw can cause several problems; the ground becomes unstable and can cause damage to infrastructure such as roads, buildings, and pipelines. It can also cause erosion and changes in the landscape, which can have ecological and social impacts and disruption of indigenous ways of life. Monitoring these changes is a key factor in reducing the impact of such disasters as well as timely reaction/adaptation to such changes. I am exploring the option of developing a change detection method using Airborne Synthetic Aperture Radar (SAR) Interferometry and Optical Photogrammetry data for precise change detection. I will present the results of our controlled experiment with simulated permafrost related changes to showcase the capability of our method in active permafrost thaw environments.
Rae Landriau will be presenting Performance of Drilling Waste Sumps, Western Arctic Canada.
Date: 29 May 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Petroleum resource exploration and development has occurred in the Northwest Territories since the 1920s. Freezing-point depressants, mainly potassium chloride, were added to drilling fluids to facilitate drilling into permafrost. Disposal of these fluids was typically in large man-made pits (sumps). Sumps were excavated in permafrost, with the intention that frozen ground would contain the fluids indefinitely. Climatic warming in northwest Canada has raised the temperature of near-surface permafrost, increasing the potential for failure of sumps in the region. Using electro-magnetic surveys, ground conductivity on and off sumps can be collected and analyzed to detect the presence of these fluids and determine if they have migrated.
Usman Iqbal Ahmed will be presenting Precise Change Detection with Airborne Interferometric Synthetic Aperture Radar (InSAR) & Optical Photogrammetry Data and its application to Active Permafrost Regions.
Date: 22 May 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Permafrost thaw can cause several problems; the ground becomes unstable and can cause damage to infrastructure such as roads, buildings, and pipelines. It can also cause erosion and changes in the landscape, which can have ecological and social impacts and disruption of indigenous ways of life. Monitoring these changes is a key factor in reducing the impact of such disasters as well as timely reaction/adaptation to such changes. I am exploring the option of developing a change detection method using Airborne Synthetic Aperture Radar (SAR) Interferometry and Optical Photogrammetry data for precise change detection. I will present the results of our controlled experiment with simulated permafrost related changes to showcase the capability of our method in active permafrost thaw environments.
Tabatha Rahman will be presenting Ice-Wedge Volume, Distribution, and Development in the Barrens of the Hudson Bay Lowlands, Northern Manitoba.
Date: 15 May 2024 Time: 13:00-14:00 Eastern Time Location: Zoom (details are posted in our Teams site).
Extensive ice-wedge polygon networks are found in the ‘Barrens’ of northern Manitoba, a 50,000 km2 zone of continuous permafrost tundra that emerged from the Tyrrell Sea less than 5,500 years ago. Tabatha will present empirical results of ice-wedge volume and tri-dimensional distribution, and will focus on the environmental conditions associated with the growth and degradation of ice wedges in this uplifted permafrost peatland. Knowledge of wedge-ice morphology and development is essential for the prediction and mitigation of risks associated with anticipated permafrost thaw in the Barrens.
