Regions: Inuvialuit Settlement Region
Tags: physical sciences, geology, active layer, permafrost, glaciology
| Principal Investigator: | Gilbert, Graham L (1) |
| Licence Number: | 14768 |
| Organization: | Carleton University |
| Licensed Year(s): |
2010
|
| Issued: | Jul 23, 2010 |
| Project Team: | Graham Gilbert (Principal Investigator), Christopher Burn (Research Supervisor), Brendan O'Neill (MSc Student) |
Objective(s): To define the impact of snow depth, surface vegetation, and soil characteristics on spatial and temporal variations in active-layer freeze-back in the low arctic tundra east of the Mackenzie Delta.
Project Description: The objectives of this project are to define the impact of snow depth, surface vegetation, and soil characteristics on spatial and temporal variations in active-layer freeze-back in the low arctic tundra east of the Mackenzie Delta. The duration of freeze back will be determined from the ground temperatures measured at the top of permafrost. This temperature only declines at the site when the active layer has frozen back as, until this time, the heat removed from the ground is supplied by the freezing of water in the active layer. Ten sites will be selected for study based on local variation in topography, vegetation, and soil moisture. The primary criterion for site selection will be topographic position, which controls snow depth in this area. Vegetation analysis, soil pit excavation, soil sampling, and active-layer measurements will be used to choose sites representative of distinct spatial units. Data loggers will be deployed at each site in conjunction with a temperature probe to a depth of one meter, placing the sensor within permafrost. Appropriate lengths of wooden doweling will be installed to mark sites for location during winter. Sensor depth is significant as winter temperature change in the permafrost will only occur following complete freezing of the active layer due to the release of latent heat during freezing. This method has been successfully implemented in earlier studies of ground temperature. Soil samples will be collected using a KRELL drill equipped with a core sampler. In addition, a series of miniature temperature loggers (Thermochron iButtons®, Model DS1921G, Dallas Semiconductor Corporation, USA) will be deployed at each site at 5, 10, 20, 30, 40, and 50 cm above the ground and attached to a section of steel pipe to prevent animal damage. Fifty cm is an appropriate height of maximum snow depth given the local conditions and historical record. This number of sites will allow for redundancy in the event that some of the sites fail to produce results. The researcher would be happy to meet with community groups over the summer to discuss research and report on progress. Also, results and any subsequent academic papers can be provided once completed. The fieldwork for this study will be conducted from July 21, 2010 to August 31, 2010.
