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TitreLocal and traditional knowledge in conjunction with geoscience data to understand permafrost conditions and guide research activities, Rankin Inlet area, Nunavut
AuteurLeBlanc, A -M; Oldenborger, G A; Bellehumeur-Génier, O
SourceArcticNet: Abstracts, 2017 International Arctic Change Conference; 2017 p. 237-238
LiensOnline - En ligne (complete volume - volume complet, pdf, 3.89 MB)
Année2017
Séries alt.Ressources naturelles Canada, Contribution externe 20170236
ÉditeurArcticNet
RéunionArcticChange 2017: 2017 International Arctic Change Conference; Québec, QC; CA; décembre 11-15, 2017
Documentlivre
Lang.anglais
Mediapapier; en ligne; numérique
Formatspdf
ProvinceNunavut
SNRC55K/16
Lat/Long OENS -92.5000 -92.0000 63.0000 62.7500
Sujetspergélisol; glace fossile; caractéristiques périglaciaires; thermokarst; recherche géologique; recherche sur les régions froides; drainage; stabilité des pentes; végétation; climat; eaux de surface; lacs; variations du littoral; rivières; niveaux d'eau; changements du niveau de la mer; précipitation; dépôts glaciaires; tills; sédiments marins; interprétations géophysiques; méthodes radar; Infrastructure communautaire; Études nordiques; géologie des dépôts meubles/géomorphologie; géophysique
ProgrammePergélisols, Géosciences de changements climatiques
Diffusé2017 12 01
Résumé(disponible en anglais seulement)
Permafrost is an important factor in the development, planning and maintenance of infrastructure in Canada's North. In the Kivalliq region, limited historical or contemporary permafrost information is available, and few permafrost maps and monitoring stations cover the study area. To initiate permafrost studies in this context, a community workshop which included a participatory mapping exercise, was organized for gathering local and traditional knowledge (LTK) on permafrost in the Rankin Inlet area and the Kivalliq region in general. The workshop was used as a scoping activity with the idea that the results would be useful to understand permafrost conditions and develop long term research activities. Participants were given a series of maps and asked to identify landscape features and areas of landscape change that might be related to permafrost and permafrost processes, including observations such as ground ice, change in drainage, and slope movement. Participants were also asked to consider how permafrost-related landscape changes might be important to them. Observations identified in the workshop were classified into categories related to water-level changes, ground movement and ground ice, slope movement, and vegetation. The workshop was followed by a preliminary field campaign to visit areas identified by the workshop participants in order to reconcile LTK observations and potential permafrost processes. In parallel, LTK observations were analysed in conjunction with geoscience data including surficial geology, climate data, ground movement based on DInSAR mapping, and historical dynamics of lake shorelines. For example, the most frequent LTK observations involved low water level in rivers, lakes, ponds and streams particularly noticed in recent years (since 2005 or 2010). Many hypotheses could explain this behavior such as falling relative sea level in the region, anthropogenic alteration of water levels or drainage patterns, changes in the precipitation regime, or active thermokarst processes. Based on an analysis of the historical dynamics of lake shorelines, the behaviour of some lakes identified by the LTK observations is consistent with lake evolution by thermokarst processes. Furthermore, analysis of the LTK observations in conjunction with geoscience data revealed that surficial geology of undifferentiated till and marine sediments is of particular interest for further permafrost characterization due to their recurring association with LTK observations, their wide distribution in the region, their association with thermokarst terrain, and with ground movement as measured by DInSAR. LTK observations supported the development of hypotheses on permafrost conditions and processes. The juxtaposition of LTK observations with field validation and geoscience data allowed testing of these hypotheses and some interpretation of permafrost conditions. However, not all LTK observations were as useful for interpreting permafrost conditions. Nevertheless, the approach has proven useful in initiating and guiding permafrost studies in the area of Rankin Inlet.
Résumé(Résumé en langage clair et simple, non publié)
Un atelier communautaire sur le pergélisol a été tenu à Rankin Inlet, Nunavut afin de collecter le savoir local et traditionnel (LTK) sur le pergélisol. Le but de l¿atelier était de vérifier l¿utilité des résultats pour 1) comprendre les conditions du pergélisol dans une région où les informations historiques et contemporaines sur le pergélisol sont rares, et 2) développer des activités de recherche à long terme. Les résultats ont été utilisés pour développer des hypothèses. Cependant, c¿est la combinaison des observations (LTK) avec des données terrain de validation et des données géoscientifiques qui a permis d¿établir une certaine interprétation des conditions du pergélisol. Un exemple est l¿observation du bas niveau d¿eau de certains lacs interprété comme étant un phénomène de thermokarst. La présence des thermokarst est importante pour connaitre les risques potentiels liés aux infrastructures. Les résultats démontrent également que l¿unité de géologie de surface constituée de till non différencié et de sédiments marins devrait faire l¿objet d¿une caractérisation du pergélisol plus poussée. L¿approche utilisée est utile pour initier et guider des études sur le pergélisol.
GEOSCAN ID306086