NWT RESEARCH DATABASE

Regions: Inuvialuit Settlement Region, Gwich'in Settlement Area

Tags: physical sciences, ground temperature, permafrost, climate change, hydrology, remote sensing

Objective(s): To investigate the impacts of natural and human disturbance on permafrost terrain and ground temperature conditions; to assess the physical and chemical characteristics of permafrost; and, to monitoring the thermal evolution of permafrost across tree line.

Project Description: The primary objectives of this research are: 1) to develop and test new methods of monitoring permafrost landscape change; 2) to investigate the impacts of natural and human disturbance on permafrost terrain and the ground temperature conditions in natural environments and in communities; 3) assess the physical and chemical characteristics of permafrost; and, 4) to monitor the thermal evolution of permafrost across tree line. To achieve the objectives the research team will implement the following methods. 1. Monitoring and tracking permafrost change will involve collection and analyses of remote sensing information. Most of this data is obtained by satellite, but some methods involve field surveys and use of unmanned aerial vehicles (UAVs). These are typically small multicopters which are very quiet. They have a mounted camera and flights are typically low level and last about 10 minutes in duration. By surveying and resurveying sites the team will be able to monitor change in disturbances impacting the landscape. Landsat satellite imagery will be analyzed to determine areas intense terrain disturbance, and may be used to track change in remote regions. The team will also use traditional field survey equipment to measure landforms and verify the data acquired by remote sensing. At some locations, remote cameras will be deployed to visualize and model phenomena including unstable slopes and thaw slumps. 2. To monitor changes in disturbed environments the team will conduct field surveys to build extremely accurate three dimensional models of the landscape. These surveys will be complemented at some locations by shallow and deep ground temperature cables. For the most part, these ground temperature sites were installed during past projects. The research team proposes to maintain these sites and continue ground temperature data collection at these locations. Some roadside sites have been established to investigate permafrost stability adjacent to road embankments and in riparian areas. 3. The physical and chemical characteristics of permafrost will be evaluated by obtaining samples from permafrost. These can be collected by a small two person portable drill (CRELL drill), or by carefully sampling the permafrost exposed by the headwalls of thaw slumps. Larger slumps will be only accessed in winter when it is safe. The samples are analyzed for ice content and geochemistry. In 2017, winter drilling will also involve a track mounted drill and drilling at locations along the Inuvik to Tuktoyaktuk Highway (ITH) to establish sentinel permafrost monitoring sites. The track mounted drill will enable samples to be retained up to 15 m depth so that the physical and chemical characteristics of permafrost can be determined. Thermistors will be placed in the boreholes and can serve as long term "sentinel monitoring sites". A total of 16 boreholes will be drilled, 9 will be located in clusters of 3 in the southern part of the Inuvik to Tuktoyaktuk Highway corridor within an area burned in 1968, 3 will be located in shrub tundra near Trail Valley Creek, 3 will be located in dwarf shrub tundra north of Parsons Lake. Disturbance will be minimal to preserve terrain integrity so that locations can serve as long-term monitoring sites. These sites will be placed at least 150 from the ITH to ensure that conditions are not impacted by the highway. The remaining boreholes will be drilled in the quarries to evaluate permafrost stability in these disturbed areas. Project researchers and community partners will be on site to obtain core samples which will be analysed at Aurora Research Institute. The research team has a long history of working closely with communities in the Gwich'in and Inuvialuit Settlement regions. This proposal is in part the continuation of a multi-year project conducted in close collaboration with the Tetlit Gwich’in Renewable Resource Committee (RRC) studying the impacts of thaw slumps on streams and rivers in the Peel Plateau. The Tetlit RRC played a central role in coordinating community logistics, organizing local research assistants and communicating results to the community. Research results will be communicated through various means including plain language presentations (ie: Inuvialuit Game Council meetings; Regional RRC meeting; Local RRC and Hunters and Trappers Committee meetings); plain language summaries; presentations to students at local schools and in the environment and natural Resources Technology program; local conferences, including NWT Cumulative Impacts Monitoring results workshops, NWT Geoscience Forum; local media; and, public Lectures. The fieldwork for this study will be conducted from March 16, 2018 to December 31, 2018.