Network research focuses on the big questions: Where and when is permafrost thaw occurring in Canada and what are the hazards arising from such change?
The research is organized in five interwoven themes requiring a critical mass and diversity of expertise that no single research group or government agency has.
Background and objectives
Theme 5 applies knowledge of permafrost systems and products developed by the network to priority problems identified by northern communities and agencies. Climate warming, especially in fall and winter, prevails across northern Canada, but has been most rapid in the western Arctic. There, warming began in 1970 and its initial effects on ground temperatures and ground surface conditions are now evident. Throughout northern Canada infrastructure designed for a stable, equilibrium permafrost environment is now at risk. Theme 5 will operate with the knowledge that (a) climate change has affected permafrost with initial consequences apparent in terrain behaviour and infrastructure performance; and (b) the effects of climate change on the ground thermal regime will continue for centuries.
The objective of Theme 5 is to support northerners in adaptation to permafrost in transition. Theme 5 projects address specific challenges due to thaw of permafrost. The overall goal is to assist northern communities to plan for and manage a changing permafrost environment by providing specific strategies to mitigate effects that are hazardous or debilitating to existing infrastructure. The projects range over several scales, from specific landscape effects near communities to incidents that occur along the length of several hundred km of linear infrastructure. The investigations are field based, to develop research capacity not only with trainee researchers, but also among members of the communities and agencies they will work with. Projects involve numerical simulation of ground thermal regimes in collaboration with Theme 3, to estimate the future magnitude of thaw effects. They also aim to provide the first comprehensive assessments world-wide of the costs that climate change is imposing upon northern agencies based upon data collected since 1995 by Yukon Government. This information will be critical for improving planning capacity in climate change adaptation.
In permafrost regions, the effects of climate change on infrastructure have largely been considered in terms of the susceptibility for thaw and loss of soil bearing capacity. The design of much infrastructure already considers the problem because construction disturbance commonly leads to ground warming by altering surface characteristics and, particularly, snow accumulation patterns. Approaches to mitigating these effects include bridging across thaw susceptible terrain, installation of air convection embankments and engineering adjustment of surface albedo. Theme 5 projects are also investigating the effect of snow management, whose potential to mitigate thaw near highway embankments has been demonstrated by modelling. Recently, the hydrologic effects of climate change have become apparent through increases in rainfall and delay and extension of freeze back in autumn to create icings. Hydrologic effects may present greater short-term hazards than more gradual thaw subsidence either following intense summer rainfall, during freshet, or with unexpected discharges in winter. Assessment of these hazards will be in collaboration with Theme 4.
Theme 5 is concentrating on providing practical approaches to mitigating thaw and on managing the changing hydrologic regime near infrastructure in ways that are effective with the mechanical and human resources that are available.
The theme develops engineering designs and strategies to support communities and agencies in adaptation of infrastructure for thawing terrain.
The four principal topics in Theme 5 concern:
1) adaptation and management of infrastructure in and between communities;
2) effects of landscape change on Arctic communities;
3) management of flowing water, especially in winter;
4) management of legacy structures with permafrost integral to the intended function.
In each case, the approach is to identify critical components of environmental systems that have changed and hence alter the foundations of infrastructure, and now require adjustments to the design basis. Specifics of design are the mandate of the engineering researchers in the theme, while the geoscientists focus on systems analysis. The groups work iteratively to converge on agreed results. Both groups use field observations to calibrate numerical models that capture the thermal regime of the terrain and built structures, and which can then be used as predictive tools. The financial analyses of the operational impact of climate change are an exception to this approach.
Theme 5 is jointly led by Ryley Beddoe (RMC) and Christopher Burn (Carleton University). Chris provides his experience studying permafrost in Yukon and the western Arctic along with his work on Transport Canada’s NTAI permafrost network. Chris provides expertise in ground thermal analysis and development of field programs with northern partners. Ryley has expertise in transportation infrastructure engineering and provides the theme her knowledge of design to mitigate effects of permafrost thaw on linear infrastructure components. Eight researchers will be trained under Theme 5, consisting of 5 MSc and 3 PhD.
Theme 5 participants bring together expertise in permafrost science and infrastructure management with relevance to specific infrastructure, communities, and landscape ecology. The theme relies on close communication between the scientific and engineering staff for diagnosis of challenges facing the infrastructure components that are examined and for testing of proposed mitigation techniques.
Pascale Roy-Léveillée provides expertise in thermokarst geomorphology, Hudson Bay Lowlands, permafrost change detection and working with community partners.
Shawn Kenny provides expertise in infrastructure maintenance and design, operational decision making and information processing for effective management of infrastructure in thawing permafrost.
Zhina Rezvani (T5-PhD1)
Title: Risk management of linear infrastructure in remote permafrost terrain: Churchill Railway.
Supervisors: Shawn Kenny with Ryley Beddoe, Pascale Roy-Léveillée and Fabrice Calmels.
Linear infrastructure is particularly at risk of damage related to frost heaving or thaw subsidence due to the extent and variety of permafrost conditions it may cross. Zhina’s project is developing an integrated approach to monitor remote northern linear infrastructure to support operational decisions. The Churchill Railway, recently reopened after railbed failure, will make a strategic case study, allowing Zhina to collaborate with others in Theme 5. Current rail inspection practices utilize visual techniques supplemented by NDT for the evaluation of rail track flaws and monitoring of changes in geometric characteristics, as well as light detection and ranging (LIDAR) and ground-penetrating radar (GPR) for the evaluation of the ballast profile and subsurface quality. However, new data (e.g. thermistors, UAV digital images) and tools (e.g. DIC, structure from motion) are needed to monitor and assess the railbed (ballast and foundation) conditions in permafrost regions, so that preventative maintenance activities (e.g. drainage, track geometry corrections) can be planned and sustainable adaptation strategies developed. Zhina is using geotechnical data obtained by drilling and geophysical surveys by GPR or electrical resistivity tomography (ERT) to define permafrost state. Remote sensing observations (optical, LiDAR, RADAR) from unmanned aerial vehicle (UAV) and satellite-based sensors are being used to estimate permafrost change and ground motion. Empirical and screening level computational tools will be developed to estimate risk for defined route segments under continuing climate warming. This knowledge base and tools will help to identify problem areas where more intensive work may be required, with consideration of hydrologic changes in peatlands.
Rae Landriau (T5-PhD3)
Title: Timing of sump stability, western Arctic coast.
Supervisors: Chris Burn with Stephan Gruber, Trevor Lantz and Steve Kokelj; internship at Aurora Research Institute.
During the 1960s and 1970s over 50 waste disposal sumps were constructed in the western Arctic during oil and gas exploration. These sumps were open pits during waste disposal, subsequently covered at closure. Permafrost, then at a mean annual temperature below -7 °C in most of the region was assumed to provide an impermeable containment medium in perpetuity. Warming of permafrost now denies this possibility. Management of these contaminated sites requires estimation of the time remaining before permafrost ceases to be an effective containment.
Rae is conducting a study of the ground thermal regime near two sumps in contrasting terrain, one in the outer Mackenzie delta and the other in the adjacent uplands, to establish the thermal regime around these structures. The project is sampling the sump materials to determine their freezing characteristics. Expertise from Theme 3 is assisting thermal modelling of the field conditions around the sumps and their projected future trajectory. The timescale associated with the thermal evolution of sumps and adjacent terrain is required for prediction of contaminant egress from these sumps. When calibrated with records collected in the region, these models will estimate if these structures are likely to be secure for decades or centuries. This is critical data for land managers in the region and for the national response to an undesirable consequence of permafrost warming. The main partner for this project is Steve Kokelj (Northwest Territories Geological Survey).
Adam Kirkwood (T5-PhD4)
Title: Land use planning and mass-wasting hazards near Fort Severn and water quality change.
Supervisors: Pascale Roy-Léveillée.
Adam’s project has 4 objectives;
1 – Identification of controls and triggering factors for mass-wasting along rivers of the Hudson Bay Lowlands (HBL)
2 – Production of maps indicating areas potentially vulnerable to slumping and currently affected by thermokarst
3 – Production of a map of mercury (Hg) stores in the Ontario portion of the Hudson Bay Lowlands
4 – Assessment of methylation and mobilisation (DOM and Hg) potential to adjacent water bodies in a range of thermokarst contexts
Fort Severn is located on the Severn River, near the Hudson Bay Coast. Recent mass-wasting activity along the river has triggered local concern that the stability of the town site may be threatened by thaw induced landslides. In partnership with Fort Severn First Nation, Adam is characterizing and comparing surficial deposits and permafrost conditions at the town site and at the sites affected by mass-wasting and use remotely sensed imagery and local knowledge to investigate past mass-wasting events, their timing, and the factors that may trigger them. Potential early warning signs are being identified in collaboration with theme 4. Conditions and slope failure characteristics will be compared to the controls on thaw slumps as identified by T4-MSc3. Maps of ground conditions and associated mass-wasting risk are being produced to facilitate planning and risk mitigation measures. These findings are then being integrated into hazard mapping in Theme 4. The main partner for this part of Adam’s project is Chief Paul Burke of Fort Severn First Nation.
Adam is also improving understanding of permafrost change contributing to water quality change via solute loading of surface waters, beginning with a review and compilation of available water quality data across a range of different environmental settings across the Canadian permafrost region to identify metrics of thaw-induced hydrochemical change. He is collaborating with network partners and investigators to deliver the first analysis of permafrost-water quality change as a benchmark for future studies. Field investigations focus on Churchill MB where permafrost coring in 2010-11 indicated the presence of high solute content in the uppermost ice-rich permafrost. This location, along with similar permafrost cores from nearby Arviat NU, indicate the potential for permafrost thaw to mobilize salts to surface waters in this region of the Hudson Bay Lowlands. This project is expanding permafrost sampling to detail near-surface ice and solute conditions, and to establish a network of hydrological monitoring and sampling to determine patterns of hydrochemical variations. Further, winter sampling of lakes across the area for water chemistry is being facilitated with support of the Churchill Northern Research Centre (CNRC) and the involvement of Dr. LeeAnn Fishback.
Adam is working on an inventory of peat and permafrost samples from 35 sites across the Hudson Bay Lowlands, installing monitoring equipment and collecting samples that are analysed at Western University for mercury concentrations. His work includes inventory of previous field sites, and the creation of a database of field observations and peat depths/stratigraphic profiles for future analysis of mercury storage in the Hudson Bay Lowlands and the profiling of microbial communities.
To facilitate the creation of a mercury inventory for the HBL, Adam is working with the Ontario Ministry of Natural Resources and Forestry (OMNRF) to develop a data sharing agreement for the procurement of additional chemical data in relation to the peat and permafrost cores provided by the partner.
Patrick Jardine (T5-MSc3)
Title: Highway embankments and snow accumulation/manipulation, Blackstone Uplands.
Supervisors: Chris Burn with Fabrice Calmels and Pascale Roy-Léveillée.
Snow accumulation on the sides of embankments is a primary cause of permafrost degradation beside northern roads. Subsidence below the embankment leads to shoulder rotation and deterioration of infrastructure. These effects have been successfully arrested in numerical simulations where snow cover is cleared or compacted to a higher density.
In collaboration with TEB, Yukon Highways and Public Works, and the Na-Cho Nyak Dun First Nation, Patrick has conducted a field experiment in snow management to validate the projections of the simulations. Snow was compacted by snowmobile or removed from multiple sites in central Yukon; beside the Dempster Highway in the Blackstone Uplands over a 1 km test section, and near Mayo, and the resulting change in ground thermal regime was established in comparison with unaffected sites. Thermal monitoring was designed with assistance from Theme 2; characterization of permafrost at the embankment toe with help from Theme 1. The results will allow maintenance staff to assess if snow management is a cost-effective strategy to arrest permafrost degradation. Simulation, with assistance from Theme 3 and once calibrated for the field site, will be used to estimate minimum maintenance required to achieve thermal stability in the embankment. Sandra MacDougall (TEB) and Steve Kokelj (NWT Geological Survey) are the main partners of this project.
Payam Sharifi (T5-MSc4)
Title: Assessing a Geocell-supported railway embankment subjected to permafrost degradation and ponding water conditions using numerical modelling techniques.
Supervisors: Ryley Beddoe with Shawn Kenny, Pascale Roy-Léveillée and Jocelyn Hayley.
The Hudson Bay Railway (HBR) is a rail corridor in Northern Manitoba built across a range of permafrost terrain and peat conditions. Every year the Hudson Bay Railway experiences a significant number of differential deformations and embankment instabilities. Recently, HBR has used geocells, a common reinforcement technique in non-permafrost soils, to improve the support of railway on the degrading permafrost and underlying peat layer. Payam’s project looked at thermo, hydro and mechanical processes using finite element analyses to examine and predict thaw deformations, settlement, and stability.
Payam’s results found that using geocell reinforcement to reduce lateral deformation is most advantageous when the active layer was between 1 – 2 m below grade. Similarly, the stability of the embankment was improved up to 50% when using a geocell at the optimal height. Payam’s research did find that the stability performance improvement using geocell will gradually diminish over the long term due to increasing dominance from permafrost degradation. This research has shown that the use of geocells in permafrost embankments can provide significant improvements to the design life of the embankment, and its application and use in future linear infrastructure designs in permafrost regions should be explored further. James Wilson and Brett Young (Arctic Gateway) are the main partners of this project.
Adeleh Zafranchi Zadeh Moqadam (T5-MSc5)
Title: Sustainable culvert design over degrading permafrost, Hudson Bay railway.
Supervisors: Shawn Kenny with Ryley Beddoe and Claude Duguay.
Recent washouts along the Churchill railway highlight how climate change has lowered the performance standards of linear infrastructure. Significant effort was made to restore the operation of the railway including installation of several culverts. With support from Sheida Majidi (T5-PhD1). Adeleh will first complete a characterization and investigation of several culverts, both original and recent installations, including characterization of permafrost and local hydrology. Culvert performance will also be assessed. The second stage of this project, conducted with assistance from Theme 3, will use computational simulations to predict culvert performance under continued and accelerated permafrost degradation. James Wilson (Arctic Gateway) and LeeAnn Fishback (CNSC) will be the main partners of this project.
Astrid Schetselaar (T5-MSc6)
Title: Asset management of linear infrastructure in southern and central Yukon.
Supervisors: Chris Burn with Shawn Kenny and Fabrice Calmels.
Linear infrastructure can be subject to significant distress due to permafrost degradation and changes in hydrologic regimes associated with climate change. In collaboration with TEB, Astrid is interrogating existing cost databases for operation and maintenance of linear road infrastructure, extending current research on the north Alaska and Dempster highways to the remainder of the Yukon network. The focus is on costs that are directly related to climate effects. This will improve planning and capacity for rehabilitation and maintenance. Astrid is detailing the financial effects of climate change in permafrost terrain to complement physical effects investigated by other Theme 5 projects. Sandra MacDougall (TEB) is the partner on this project.
Collaborators and partners
- F. Calmels
- S.V. Kokelj
- M. Packalen
- S. MacDougall
- C. Stevens
- L. Arenson
- L. Fishback
- J. McLaughlin
Peer-reviewed research findings are listed on our Publications page.