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Climate-driven sea ice loss has led to changes in the timing of key biological events in the Arctic, however, the consequences and rate of these changes remain largely unknown. Polar bears (Ursus maritimus) undergo seasonal changes in energy stores in relation to foraging opportunities and habitat conditions. Declining sea ice has been linked to reduced body condition in some subpopulations, however, the specific timing and duration of the feeding period when bears acquire most of their energy stores and its relationship to the timing of ice break-up is poorly understood. We used community-based sampling to investigate seasonality in body condition (energy stores) of polar bears in Nunavut, Canada, and examined the influence of sea ice variables. We used adipose tissue lipid content as an index of body condition for 1,206 polar bears harvested from 2010-2017 across five subpopulations with varying seasonal ice conditions: Baffin Bay (October-August), Davis Strait and Foxe Basin (year-round), Gulf of Boothia and Lancaster Sound (August-May). Similar seasonal patterns were found in body condition across subpopulations with bears at their nadir of condition in the spring, followed by fat accumulation past break-up date and subsequent peak body condition in autumn, indicating that bears are actively foraging in late spring and early summer. Late season feeding implies that even minor advances in the timing of break-up may have detrimental effects on foraging opportunities, body condition, and subsequent reproduction and survival. The magnitude of seasonal changes in body condition varied across the study area, presumably driven by local environmental conditions. Our results demonstrate how community-based monitoring of polar bears can reveal population-level responses to climate warming in advance of detectable demographic change. Our data on the seasonal timing of polar bear foraging and energy storage should inform predictive models of the effects of climate-mediated sea ice loss., (© 2019 John Wiley & Sons Ltd.)

Permafrost in northern Canada is susceptible to degradation due to rapid climate change, with hazard mapping promoted as an important activity to guide sustainable community adaptation and planning. This paper presents a framework for evaluating permafrost mapping exercises designed to inform climate change adaptation actions. We apply the framework using a case study of the Incorporating Climate Change into Land Development—Terrain Analysis project (ICCiLD). ICCiLD is a hazard mapping project utilizing interferometric synthetic aperture radar to monitor ground disturbance and categorize land development suitability in seven communities in the territory of Nunavut, Canada. We looked at one of the communities, Arviat, as our case study. We examined technical data and drew upon semi-structured interviews (n = 19) with map creators and users. We found ICCiLD added new and relevant information for community planning, increased awareness of the risks posed by permafrost thaw and built stakeholder relations. Strong coordination and high public consciousness of local climate impacts emerged as key factors underpinning project success. Nevertheless, in the case of Arviat, the effectiveness of the hazard maps in influencing land-use planning was constrained by communication challenges between project creators and end-users. These challenges included limited community access to the data and uncertainty surrounding how to operationalize the map suitability classifications. Broader climate change adaptation challenges included the presence of other more immediate community planning priorities and a limited ability to incorporate Indigenous ways of knowing into a technical mapping project. The lessons from this evaluation provide insight for the development of mapping-based adaptations across Arctic regions. [ABSTRACT FROM AUTHOR]

The paper is concerned with thermal disturbances in continuous permafrost due to open pit mining and tailings impoundment in the cold regions of Northern Canada. Numerical simulations were conducted to investigate issues of thermal regime changes and permafrost degradation in both the short term and the long term in connection with the proposed Kiggavik project in Nunavut, Canada. The results of numerical simulations indicate that no open talik would form below the East Zone and Center Zone pits during the estimated mining and milling operation period of 14 years, although a thin thawed zone would develop surrounding the open pits. For the Main Zone pit where the excavation would break through permafrost, the open talik remains following an extended operation period of 25 years with a 5 to 30 m thawed zone along the pit side walls. In the long term, with a plausible climate change scenario of 5 °C increase in the mean annual ground surface temperature during the next 100 years, the permafrost surrounding the in-pit tailings management facilities (TMFs) would reduce greatly in about 500 years. However, an approximately 40 m thick permafrost layer would remain on the top of the TMFs, which is impervious and would prevent any tailings pore water from migrating upward to reach the ground surface. [ABSTRACT FROM AUTHOR]

Injury is the leading cause of death for Canadians aged 1 to 44, occurring disproportionately across regions and communities. In the Inuit territory of Nunavut, for instance, unintentional injury rates are over three times the Canadian average. In this paper, we develop a framework for assessing vulnerability to injury and use it to identify and characterize the determinants of injuries on the land in Nunavut. We specifically examine unintentional injuries on the land (outside of hamlets) because of the importance of land-based activities to Inuit culture, health, and well-being. Semi-structured interviews (n = 45) were conducted in three communities that have varying rates of search and rescue (SAR), complemented by an analysis of SAR case data for the territory. We found that risk of land-based injuries is affected by socioeconomic status, Inuit traditional knowledge, community organizations, and territorial and national policies. Notably, by moving beyond common conceptualizations of unintentional injury, we are able to better assess root causes of unintentional injury and outline paths for prevention. [ABSTRACT FROM AUTHOR]