Using examples from three case studies in Yukon communities, we investigate the role of anthropogenic disturbance on permafrost landscapes. Landscape modifications investigated include alternations to surface vegetation for fire protection adjacent to communities, and land clearing to support economic activities like surface mining and agriculture. In most cases, the removal of protective vegetative cover resulted in permafrost degradation, leading to the development of near-surface taliks over decadal-scale time periods. Conversely, light alteration to vegetative cover (e.g., stand thinning for fire protection) does not appear to have altered permafrost presence or distribution. Results have implications for community-scale land use planning in the context of a changing climate. RÉSUMÉ Trois études de cas ont été sélectionnées dans les communautés du Yukon afin d’illustrer les impacts des perturbations anthropiques sur les environnements à pergélisol. Les modifications des paysages étudiés incluent la coupe sélective des zones boisées pour la prévention de feu de forêts dans les communautés avoisinantes ainsi que le défrichage des terres pour soutenir certaines activités économiques telles que l’industrie minière et l’agriculture. Dans la plupart des cas l’élimination du couvert végétal a entrainé la dégradation du pergélisol, ce qui aurait contribué à la création de taliks à l'échelle décennale. Cependant, l’altération de la couverture végétale pour la prévention de feux de forêt ne semble pas avoir modifié l’état du pergélisol. Les résultats de cette étude serviront aux communautés, afin de mieux planifier l’utilisation du territoire dans le contexte des changements climatiques.

For northern regions underlain by permafrost, the projected increase in temperatures will greatly impact the physical properties of soils and their capacity to support infrastructure. In this context, the need to identify land parcels to build new housing in a safe and sustainable manner is pressing in Nunavik (northern Quebec, Canada). To guide residential development in these particular settings, this paper presents a GIS-based approach developed to identify terrain sensitivity to thaw-settlement and mass movements, geomorphological processes responsible for costly readaptation or relocation of infrastructure. Land-suitability assessment for residential development in permafrost regions requires the consideration of many factors that may interact in complex ways. Combining factors to assess suitability presents a number of challenges that are especially important to resolve in permafrost-region studies to guide fine-scale decisions. Using an example of a GIS system built for the village of Tasiujaq in Nunavik, this paper illustrates some of the specific challenges to the effective use of GIS for management in permafrost regions. Temporal, existential and representational limits are inherent to the use of GIS and important to consider in land planning for permafrost studies. This paper also demonstrates how permafrost science can benefit from GIS technologies, especially their capacity of adaptation and transformation to any scenarios and changes in environmental parameters.

Northern Quebec (Nunavik) presents an important intersection between population growth and climate change. The Inuit population of Nunavik has the fastest growth rate in any region of Canada. Land-use planning is an urgent and pressing need for northern communities built on permafrost, where there are considerable risks to development in areas where permafrost may thaw. As northern communities work to adapt to climate changes, they will be in great need of confident recommendations about locations of future development projects. This paper presents a case-study of the community of Tasiujaq and assesses the probability of thaw settlement of the surface, a process seriously affecting infrastructure stability. A method is developed for quantifying uncertainty in the resulting map, expressed as a function of judgmentbased uncertainty in the various factors that can influence eventual map quality. The best estimate of vulnerability and of the confidence in that estimate can be expressed in a single, simple map that allows an analyst to convey both of these vital aspects of the assessment process.