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Ancient greenhouse periods are useful analogs for predicting effects of anthropogenic climate change on regional and global temperature and precipitation patterns. A paucity of terrestrial data from polar regions during warm episodes challenges our understanding of polar climate responses to natural/anthropogenic change and therefore our ability to predict future changes in precipitation. Ellesmere and Axel Heiberg Islands in the Canadian Arctic preserve terrestrial deposits spanning the late Paleocene to middle Eocene (59–45 Ma). Here we expand on existing regional sedimentology and paleontology through the addition of stable (δ13C, δ18O) and clumped (Δ47) isotope analyses on palustrine carbonates. δ13C isotope values range from −4.6 to +12.3‰ (VPDB), and δ18O isotope values range from −23.1 to −15.2‰ (VPDB). Both carbon and oxygen isotope averages decrease with increasing diagenetic alteration. Unusually enriched carbon isotope (δ13C) values suggest that analyzed carbonates experienced repeated dissolution‐precipitation enrichment cycles, potentially caused by seasonal fluctuations in water availability resulting in summer carbonate dissolution followed by winter carbonate re‐precipitation. Stable isotopes suggest some degree of precipitation seasonality or reduction in winter water availability in the Canadian Arctic during the Paleogene. Clumped (Δ47) temperature estimates range from 52 to 121°C and indicate low temperature solid‐state reordering of micritic samples and diagenetic recrystallization in sparry samples. Average temperatures agree with vitrinite reflectance data for Eureka Sound Group and underlying sediments, highlighting structural complexity across the region. Broadly, combined stable and clumped isotope data from carbonates in complex systems are effective for describing both paleoclimatic and post‐burial conditions. Plain Language Summary: Paleogene paleohydrology in Arctic Canada has been a question of much debate in recent years, with competing ideas about conditions characterized as either "polar monsoon" or "ever‐wet" regimes. Proxy records from Ellesmere and Axel Heiberg islands have been central to this debate, but complex stratigraphy and burial histories have hampered a resolution. Here we employ a combined carbonate isotope (δ13C, δ18O, Δ47) approach to disentangle paleoclimate and diagenetic signals. Using palustrine carbonates (which host previously evaluated paleobotanical remains) within a new stratigraphic framework, we demonstrate that δ13C and δ18O values from primary‐fabric samples indicate a distinct, but non‐monsoonal hydrologic seasonality during the late Paleocene/early Eocene. We also demonstrate that Δ47 temperatures reflect both shallow burial reordering and more intense remineralization, which are consistent with vitrinite reflectance studies showing variable deformation and geothermal gradients in the Sverdrup Basin. This combined isotopic approach is novel in the region, and can be applied to other regions of interest in deep time. Key Points: Combined carbonate isotope approach disentangles paleoclimate/diagenesis despite complex environmental histories on Ellesmere/Axel HeibergCarbon and oxygen isotope values highlight hydrologic seasonality in the Arctic during the PaleogeneTemperatures from carbonate clumped isotopes are consistent with vitrinite reflectance burial temperature, suggesting variable deformation [ABSTRACT FROM AUTHOR]

The Canadian Arctic is a complex and fragile region which is currently experiencing unprecedented environmental degradation due to climate change. The effects of climate change on the Canadian Arctic is just one example where we're seeing the decline of ecosystems and socio-culture-environmental traditions. Mineral development in this already fragile ecosystem is indeed a contentious and high-risk endeavour. However, mining is currently one of the few industries and economic development opportunities in the Canadian Arctic, which is one of the poorest regions in Canada. Unfortunately, mining struggles to achieve environmental sustainability due to mineral development's inherent trade-off of short-term economic gains for long-term environmental impacts. Local communities are usually left with trying to find this balance. This paper analyzes how we can apply decision-making techniques and environmental management tools for the Canadian Arctic's mining industry to promote better environmental sustainability, understanding of environmental-economic trade-offs, and community involvement. Specific decision-making methodologies and management tools are analyzed to develop, discuss, and explore their application for the Canadian Arctic. This paper concludes with a framework that brings together the analyzed methods and Arctic specificities; to prioritize environmental issues and to ensure long-term thriving communities in the Arctic. [ABSTRACT FROM AUTHOR]

Throughout his tenure as Prime Minster of Canada (2006-2015), Stephen Harper had a particular fascination with the Canadian North, illustrated in part by his annual tours of the Canadian Arctic and Subarctic region. Using these tours as a case study, this paper argues that state discourses of sovereignty, resource development, and climate change are intertwined with the simultaneous production of a tourist landscape. This tourist landscape is established in part through the circulation of affect within state discourses, like those engaged by Harper on his northern tours. The affective economies of tourism in the Canadian Arctic are heavily intertwined with both market-focused policy objectives and the moral imperative established by climate change. The result is a discourse of northern Canada that puts it within the purview of southern Canada. In particular, the affective, economic, and ecological dynamics in northern Canada produce an image of the North as both a playground for southern desires and a place in danger that is in need of saving. This moral economy in the North proposes market-based solutions and ethics for both economic and environmental problems. [ABSTRACT FROM AUTHOR]

Using satellite remote sensing, this study aims to assess the validity of upscaling ground‐based structural observations of small valley glaciers, to larger‐scale ice masses that are too vast or inaccessible for field‐study or ground‐truthing. Focusing on four adjacent valley glaciers on Bylot Island, Nunavut, Arctic Canada, we establish that ground‐based structural observations from two smaller (Stagnation and Fountain Glaciers) can be used to interpret the structures visible in optical satellite imagery in two much larger glaciers (Aktineq and Sermilik Glaciers). All the glaciers investigated have prominent longitudinal lineations, which are interpreted from ground observations to be longitudinal foliation. Other structures that were identified include primary stratification, crevasses, crevasse traces, and thrust‐faults. Strong longitudinal foliation is concentrated at flow‐unit boundaries, with differential ablation of ice facies commonly resulting in a ridge‐and‐furrow supraglacial topography that controls supraglacial streams and debris concentrations. Consequently, areas of strong foliation appear darker than areas of weak foliation in satellite imagery. As coarser resolution imagery is utilized to map large‐scale ice masses, sub‐pixel structural information is lost. Individual lineations mapped in coarser resolution imagery therefore probably comprise groups of clustered foliation at the sub‐pixel scale. Lateral narrowing measurements and calculated one‐dimensional strain across zones of longitudinal foliation are assessed as a tool for identifying large‐scale surface strain patterns, in particular large‐scale pure shear regimes. These one‐dimensional strain measurements suggest that flow‐unit boundaries are areas that undergo considerable cumulative strains. The upscaling approach used here can be applied to the largest ice masses, notably the Antarctic Ice Sheet. [ABSTRACT FROM AUTHOR]

Environmental changes are affecting the Arctic at an unprecedented rate, but limited scientific knowledge exists on their impacts on species such as walruses (Odobenus rosmarus). Inuit Traditional and Local Ecological Knowledge (Inuit TEK/LEK) held by Inuit walrus harvesters could shed light on walrus ecology and related environmental changes. Our main objective was to study spatial and temporal changes in Atlantic walrus (Odobenus rosmarus rosmarus) distribution in Nunavik (northern Québec, Canada) using Inuit TEK/LEK. To do so, we documented the knowledge and observations of 33 local hunters and Elders as part of a larger project on Atlantic walruses in Nunavik. We first gathered information on changes in Inuit land use patterns and harvesting practices through time and space, which was a crucial step to avoid potential biases in interpreting local observations on walrus distribution. We found that walrus hunters are now covering smaller hunting areas over shorter time periods, reducing in space and time their observations of Atlantic walruses around Nunavik. While clearly taking these limitations into account, we learned from interviews that some areas abandoned by Atlantic walruses in the past were now being re-occupied. Importantly, Atlantic walruses, which migrate following the melting ice, are now traveling along the eastern coast of Nunavik one month earlier, suggesting that Atlantic walrus migration has changed due to variations in sea-ice coverage around Nunavik. Our study not only highlighted important changes in Atlantic walrus distribution and migration in Nunavik, but also sheds light on the importance of documenting temporal and spatial changes in Inuit land use patterns and harvesting practices to understand the ecology of Arctic species using Inuit Knowledge. [ABSTRACT FROM AUTHOR]

Pinnipeds generally swallow prey whole, and most have simple, homodont, nonoccluding cheek teeth. We investigated whether cheek teeth in seals are more variable and weakly integrated than in terrestrial Carnivora. We measured mandibular length and crown length of mandibular postcanines (PCs) in ringed seals (Pusa hispida; n = 912) from the Canadian Arctic, and harp seals (Pagophilus groenlandicus; n = 636) from Newfoundland and Labrador. PC size was uncorrelated or only weakly correlated with adult mandibular length. PC length and mandibular length were strongly bilaterally symmetrical (r ≥ 0.8 between left and right sides). PC size was moderately variable (coefficients of variation [CVs] ~ 7-10%), and CV varied with position in the toothrow. Adjacent PCs were correlated more strongly in size (to r > 0.8) than PCs more distant from one another. In summary, PC size in ringed and harp seals was slightly more variable than cheek teeth in complex dentitions of fissipeds, and the 2 seals were similar to fissipeds in strong bilateral symmetry in mandibular and PC size, patterned variation along the toothrow, and correlated size between adjacent PCs. [ABSTRACT FROM AUTHOR]

In 2014, through the World-Class Tanker Safety System (WCTSS) initiative, the Government of Canada launched the Northern Marine Transportation Corridors (NMTC) concept. The corridors were created as a strategic framework to guide Federal investments in marine transportation in the Arctic. With new government investment, under the Oceans Protection Plan (OPP), the corridors initiative, known as the Northern Low-Impact Shipping Corridors, will continue to be developed. Since 2016, the Canadian Hydrographic Service (CHS) has been using the corridors as a key layer in a geographic information system (GIS) model known as the CHS Priority Planning Tool (CPPT). The CPPT helps CHS prioritize its survey and charting efforts in Canada's key traffic areas. Even with these latest efforts, important gaps in the surveys still need to be filled in order to cover the Canadian waterways. To help further develop the safety to navigation and improve survey mission planning, CHS has also been exploring new technologies within remote sensing. Under the Government Related Initiatives Program (GRIP) of the Canadian Space Agency (CSA), CHS has been investigating the potential use of Earth observation (EO) data to identify potential hazards to navigation that are not currently charted on CHS products. Through visual interpretation of satellite imagery, and automatic detection using artificial intelligence (AI), CHS identified several potential hazards to navigation that had previously gone uncharted. As a result, five notices to mariners (NTMs) were issued and the corresponding updates were applied to the charts. In this study, two AI approaches are explored using deep learning and machine learning techniques: the convolution neural network (CNN) and random forest (RF) classification. The study investigates the effectiveness of the two models in identifying shoals in Sentinel-2 and WorldView-2 satellite imagery. The results show that both CNN and RF models can detect shoals with accuracies ranging between 79 and 94% over two study sites; however, WorldView-2 images deliver results with higher accuracy and lower omission errors. The high processing times of using high-resolution imagery and training a deep learning model may not be necessary in order to quickly scan images for shoals; but training a CNN model with a large training set may lead to faster processing times without the need to train individual images. [ABSTRACT FROM AUTHOR]