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Vulnerability to climate change is highly dynamic, varying between and within communities over different timescales. This paper draws upon complex adaptive systems thinking to develop an approach for capturing, understanding, and monitoring climate vulnerability in a case study from northern Canada, focusing on Inuit food systems. In the community of Ulukhaktok, Northwest Territories, we followed 10 hunters over a 2-year period, asking them to document their harvesting activities and discuss their lived experience of harvesting under changing environmental and societal conditions. GPS monitoring and participatory mapping sessions were used to document 23,996km of trails (n = 409), with conversational bi-weekly semi-structured interviews and secondary instrumental weather data used to contextualise climate change within a nexus of other socioeconomic, cultural, and political stressors that also affect harvesting. Our results demonstrate that climate change has considerable potential to affect harvesting activities, particularly when its impacts manifest as anomalous/extreme events. However, climate change impacts are not necessarily the most salient issues affecting harvesting on a day-to-day basis. Instead, factors relating to economics (particularly financial capital and the wage-based economy), social networks, and institutions are found to have a greater influence, either as standalone factors with cascading effects or when acting synchronously to augment the impacts of environmental change. [ABSTRACT FROM AUTHOR]

While the authors of current bridge management systems (BMSs) have noted the need for expanding the systems to include more functional aspects of bridge performance, to date no method has been proposed for the incorporation of bridge rating against climate change impacts. This paper presents a new procedure for extending the asset management scope for highway bridges to incorporate the bridges' resilience or vulnerability against climate change impacts. The proposed procedure draws from the projected demands of climate change--a worldwide phenomenon that is expected to produce its most dramatic impacts in cold regions. The following bridge resilience indicators are proposed: abutment washout, pier scour, abutment erosion, deck flooding, and abutment permafrost stability. The formulations for the proposed indicators require weights to be assigned to each indicator. The other requirement comprises capacity measures that indicate how well a bridge is equipped to withstand the projected climatic effects. The new procedure has been applied to 14 highway bridges in the Canadian Arctic to demonstrate how public investments in transportation infrastructure could be better managed and protected. The method comes with an Inspection Form that transportation agencies and their bridge inspectors can use for rating bridges on climate change resilience. [ABSTRACT FROM AUTHOR]

There is significant evidence that northern Canada's climate has already undergone substantial change. These changes have meant significant impacts for physical, natural and human systems in Canada's North. Climate models suggest that such trends will continue into the future, and therefore shifts in Arctic systems are expected for some time to come. This introductory paper is the first in a series published in two issues of Ambio presenting work conducted for northern chapters of two recent Canadian national climate science assessment initiatives, From Impacts to Adaptation: Canada in a Changing Climate 2007 and Human Health in a Changing Climate: A Canadian Assessment of Vulnerabilities and Adaptive Capacity. Collectively, these assessments involved the work of 24 scientists with expertise in a variety of disciplines and regions in the Canadian North. These assessment processes adopted aspects of a vulnerability approach to climate assessment, primarily through a review of existing and projected exposures and elements of adaptive capacity based on existing literature. In so doing, they have contributed towards a more comprehensive understanding of climate impacts and adaptations across the northern regions of the country. This paper provides an overview and introduction to the series of papers contained in the two issues of Ambio. [ABSTRACT FROM AUTHOR]

A study of the relationship between natural hazards and climate change in the international context provides the background for a discussion of the expected changes. In the context of this global discussion, this paper reviews the current perspectives of those natural hazards that are likely to be influenced by climate change, using northern Canada as a regional case study. The northern implications of the United Nations Framework Convention on Climate Change are examined, including the status of climate change action by the northern territorial governments, the evolving role of indigenous people, and the responsibility for climate change impacts. The difficulties surrounding natural hazards research in remote locations, and the approaches of indigenous people to natural hazards are then presented. The paper concludes with a suggested policy approach for climate change and natural hazards in northern Canada, underscoring the need for more comprehensive adaptive strategies to complement the current tendency to focus on the mitigation of greenhouse gases produced in this region. [ABSTRACT FROM AUTHOR]

This paper examines the role of Inuit traditional ecological knowledge (TEK) in adaptation to climate change in the Canadian Arctic. It focuses on Inuit relationships with the Arctic environment, including hunting knowledge and land skills, and examines their roles in adaptation to biophysical changes that affect subsistence hunting. In several instances, TEK underpins competency in subsistence and adaptations to changing conditions, which includes flexibility with regard to seasonal cycles of hunting and resource use, hazard avoidance through detailed knowledge of the environment and understanding of ecosystem processes, and emergency preparedness, e.g., knowing what supplies to take when traveling and how to respond in emergency situations. Despite the documented importance of TEK in adaptation and in maintaining a level of competency in subsistence, the relationships between TEK and adaptation to climate change are not well defined in the scholarly literature. This paper aims to conceptualize the relationships between TEK and adaptation to climate change by drawing on case study research with Inuit in the Canadian Arctic. TEK is considered an element of adaptive capacity (or resilience) that is expressed as adaptation if TEK is drawn upon to adapt to changing conditions. This capacity depends on the development, accumulation, and transmission of TEK within and among generations. [ABSTRACT FROM AUTHOR]

The benefits provided by natural (e.g., non-engineered) tundra wetlands for the treatment of municipal wastewater in the Canadian Arctic are largely under-studied and, therefore, undervalued in regard to the treatment service wetlands provide to small remote Arctic communities. In this paper we present case studies on two natural tundra systems which at the time of study had different management practices, in which one consisted of a facultative lake system continuously discharging into a tundra wetland, while the second system had wastewater discharged directly into a tundra wetland. We also examine the utility of the SubWet 2.0 wetland model and how it can be used to: (i) predict the outcomes of management options; and (ii) to assess treatment capacity within individual tundra wetlands to meet future needs associated with population growth and to help municipalities determine the appropriate actions required to achieve the desired level of treatment, both currently, and in a sustainable long-term manner. From this examination we argue that tundra wetlands can significantly augment common treatment practices which rely on waste stabilization ponds, by recognizing the services that wetlands already provide. We suggest that treatment targets could be more achievable if tundra wetlands are formally recognized as part of a hybridized treatment system that incorporates the combined benefits of both the waste stabilization pond and the tundra wetland. Under this scenario tundra wetlands would be recognized as part of the treatment process and not as the 'receiving' environment, which is how most tundra wetlands are currently categorized. [ABSTRACT FROM AUTHOR]

Abstract: This paper provides an account of ‘vital ecosystem security’. The central claim is that ‘vital ecosystem security’ and the processual ontology of ‘complex adaptive becoming’ provide useful terms with which to think environmental citizenship biopolitically within the contingent matrix of climate change. The paper identifies how complex adaptation, the operative form of vital ecosystem security, defines an emerging form of environmental citizenship, which can be found operating at the interface of a new type of forestry and the global carbon cycle. The specific case developed here concerns the boreal forest of northern Canada. [Copyright &y& Elsevier]

Environmental change in the Canadian Arctic has implications for livelihoods, food systems, infrastructure and Inuit culture. Although Inuit communities are located in industrialized countries, their integral connections with the natural environments contribute to significant exposures and sensitivities to changing conditions. This paper characterizes the vulnerability of Tuktoyaktuk in the western Canadian Arctic to climate change in the context of ongoing socio-economic and environmental changes. Existing stresses in the community influence infrastructure, livelihoods and wellbeing. Strategies for adapting to adverse conditions have largely been tactical and short term, rather than planned actions in anticipation of changes in climate. In light of projected intensification of climate change and a proposed natural gas pipeline in the Tuktoyaktuk area, the community is expected to experience new stresses in the future. Future adaptation planning and policy needs to enable community involvement in the protection of important community attributes. [ABSTRACT FROM AUTHOR]

Global climate change and its impact on public health exemplify the challenge of managing complexity and uncertainty in health research. The Canadian North is currently experiencing dramatic shifts in climate, resulting in environmental changes which impact Inuit livelihoods, cultural practices, and health. For researchers investigating potential climate change impacts on Inuit health, it has become clear that comprehensive and meaningful research outcomes depend on taking a systemic and transdisciplinary approach that engages local citizens in project design, data collection, and analysis. While it is increasingly recognised that using approaches that embrace complexity is a necessity in public health, mobilizing such approaches from theory into practice can be challenging. In 2009, the Rigolet Inuit Community Government in Rigolet, Nunatsiavut, Canada partnered with a transdisciplinary team of researchers, health practitioners, and community storytelling facilitators to create the Changing Climate, Changing Health, Changing Stories project, aimed at developing a multi-media participatory, community-run methodological strategy to gather locally appropriate and meaningful data to explore climate-health relationships. The goal of this profile paper is to describe how an EcoHealth approach guided by principles of transdisciplinarity, community participation, and social equity was used to plan and implement this climate-health research project. An overview of the project, including project development, research methods, project outcomes to date, and challenges encountered, is presented. Though introduced in this one case study, the processes, methods, and lessons learned are broadly applicable to researchers and communities interested in implementing EcoHealth approaches in community-based research. [ABSTRACT FROM AUTHOR]

Abstract: Over the past decade research examining the human dimensions of climatic change in the Arctic has expanded significantly and has become the dominant framework through which the relations between northern peoples and climatic change are understood by scholars, policy makers, political leaders, and the media. This paper critically examines the assumptions, exclusions, and orientations that characterize this broad literature, and suggests revising and expanding the terms upon which it is carried out. It focuses in particular on the exclusion of colonialism from the study of human vulnerability and adaptation to climatic change, the framing of Indigenous peoples and communities in terms of the local and the traditional, and the ways in which efforts to improve the lives of northern Indigenous peoples risk perpetuating colonial relations. The paper argues that these exclusions and orientations lead scholars to systematically overlook the immense importance of resource extraction and shipping as human dimensions of climatic change in the Canadian Arctic, and it examines the implications of such oversights. [Copyright &y& Elsevier]

Copyright of Canadian Journal of Civil Engineering is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The effects of climate change on northern vegetation productivity need to be fully understood in order to reduce uncertainties in predicting vegetation distributions under different climate warming scenarios. Knowledge of the relationship between northern climate and vegetation productivity will also help provide a better understanding of changes in vegetation distributions as an indicator of climate change and variability. Vegetation productivity and biomass have been monitored using long-term satellite earth observations, mostly using the Normalized Difference Vegetation Index (NDVI), as a cumulative indicator of all effects resulting from processes related to climate change, including changes in temperature, precipitation, and disturbance. In this paper, the investigation is focused on the short-term effect of temperature anomalies on arctic and tree-line transition vegetation productivity in both dry and humid regions of Canada. The analysis shows that several land-cover types composed mainly of trees and shrubs exhibit a significant increase in NDVI with higher-than-normal temperatures in the preceding 10-40-day period, while land-cover types consisting of lichen and moss growing on mostly barren surfaces show a significant NDVI decrease with increased temperature. These trends are consistent with results reported in plot-warming experiments in the north, which have shown that certain vegetation communities increase, while others decrease in cover fraction and biomass in response to warming. When land cover is grouped into increasing and decreasing NDVI with temperature and stratified by dry and humid regions of Canada, much of the dry region of northern Canada does not exhibit significant NDVI response to preceding temperature anomalies. It is expected that in the absence of disturbance or other limiting factors, an increased frequency of elevated temperature anomalies may eventually contribute to changes in vegetation biomass. A map of land-cover types that have the potential to increase in biomass with climate warming and those that are vulnerable to decline is presented. [ABSTRACT FROM AUTHOR]

The Mackenzie River is a major transportation route serving many remote northern Canadian communities and mining sites. The river is only navigable during the summer and early fall, when clear of ice. However, the river’s water conditions have changed significantly in recent years, and are expected to continue to do so, resulting in increased uncertainty for waterway transport. This paper presents a model for providing guidance to shipping companies, customers, and government on how shipping patterns may need to evolve to effectively adapt to changing climate conditions. Future freight volumes are forecasted using time series analysis. Then, logistics cost optimization is used to incorporate predicted water flow profile changes in shipping companies’ future delivery schedule planning. Results indicate that future waterway freight delivery capacities in September and October may be insufficient to transport forecasted volumes, and shipping companies may be advised to arrange for increased delivery activities in June and July. If delivery capacities are constrained by equipment and crew availability rather than water conditions in the first half of the shipping season, shipping companies may also need to take advantage of earlier anticipated ice breakup to begin the delivery season earlier. Incorporating this method for climate change adaptation in freight schedule planning may aid both shipping companies and government agencies in rethinking current practices. The method is particularly suitable for a region where harsh environmental conditions, climate change, and extreme remoteness have an overwhelming impact on operations, and logistical delays are considered quite differently from supply chains further south. [ABSTRACT FROM AUTHOR]

We analyze minimum and maximum daily temperature records from weather stations situated in the Canadian Arctic area and investigate scaling properties and their change over time. Detrended fluctuation analysis is applied to the entire available records, as well as to successive non-overlapping temporal windows. Scaling is found for intervals of 1-2 months to 5-8 years, with most exponents in the range 0.70 ± 0.05. Exponents are subject to temporal change that is found significant when compared with 95 % confidence intervals. Patterns of change are shared by groups of stations in spite of the distances separating their locations. Defining regions characterized by similar patterns of change may be possible, but such a classification should not be expected to be constant: region boundaries shift over time. [ABSTRACT FROM AUTHOR]

Climate warming in regions of ice‐rich permafrost can result in widespread thermokarst development, which reconfigures the landscape and damages infrastructure. We present multisite time series observations which couple ground temperature measurements with thermokarst development in a region of very cold permafrost. In the Canadian High Arctic between 2003 and 2016, a series of anomalously warm summers caused mean thawing indices to be 150–240% above the 1979–2000 normal resulting in up to 90 cm of subsidence over the 12‐year observation period. Our data illustrate that despite low mean annual ground temperatures, very cold permafrost (<−10 °C) with massive ground ice close to the surface is highly vulnerable to rapid permafrost degradation and thermokarst development. We suggest that this is due to little thermal buffering from soil organic layers and near‐surface vegetation, and the presence of near‐surface ground ice. Observed maximum thaw depths at our sites are already exceeding those projected to occur by 2090 under representative concentration pathway version 4.5. Plain Language Summary: Permafrost is ground that remains at or below 0 °C for two years or longer and it underlies much of the Arctic. Permafrost in Arctic lowland regions is frequently characterized by large volumes of ground ice which, when it melts, causes the ground surface to collapse. As the Arctic warms, ice‐rich permafrost degradation is expected to be widespread. Our data illustrate that very cold permafrost, which has a mean annual ground temperature of −10 °C or lower, is experiencing a rapid increase in active layer thickness at annual time scales. At three permafrost monitoring sites in the Canadian Arctic we have observed that warmer than average summer air temperatures have caused the active layer to deepen, near‐surface ground ice to melt, and the overlying ground surface to subside, in some cases leading to the formation of small thaw ponds. Our results show that very cold permafrost terrain is responding rapidly to ongoing warming. Key Points: Observed thermokarst development in very cold permafrost at three monitoring sites along a 700‐km transect in the Canadian High ArcticRapid landscape response to above average summer warmth is due to limited thermal buffering from overlying ecosystem components and near‐surface ground iceChange was greatest at Mould Bay where thawing index values were 240% above historic normals causing ~90 cm of subsidence in 12 years [ABSTRACT FROM AUTHOR]

Changes in the form of precipitation have a considerable impact on the Arctic cryosphere and ecological system by influencing the energy balance and surface runoff. In this study, station observations and ERA-Interim data were used to analyze changes in the rainfall to precipitation ratio (RPR) in northern Canada during the spring-summer season (March-July) from 1979-2015. Our results indicate that ERA-Interim describes the spring-summer variations and trends in temperature and the RPR well. Both the spring-summer mean temperature [0.4°C-1°C (10 yr)-1] and the RPR [2%-6% (10 yr)-1] increased significantly in the Canadian Arctic Archipelago from 1979-2015. Moreover, we suggest that, aside from the contribution of climate warming, the North Atlantic Oscillation is probably another key factor influencing temporal and spatial differences in the RPR over northern Canada. [ABSTRACT FROM AUTHOR]

In the framework of developing a global modeling system which can facilitate modeling studies on Arctic Ocean and high- to midlatitude linkage, we evaluate the Arctic Ocean simulated by the multi-resolution Finite Element Sea ice-Ocean Model (FESOM). To explore the value of using high horizontal resolution for Arctic Ocean modeling, we use two global meshes differing in the horizontal resolution only in the Arctic Ocean (24 km vs. 4.5 km). The high resolution significantly improves the model's representation of the Arctic Ocean. The most pronounced improvement is in the Arctic intermediate layer, in terms of both Atlantic Water (AW) mean state and variability. The deepening and thickening bias of the AW layer, a common issue found in coarse-resolution simulations, is significantly alleviated by using higher resolution. The topographic steering of the AW is stronger and the seasonal and interannual temperature variability along the ocean bottom topography is enhanced in the high-resolution simulation. The high resolution also improves the ocean surface circulation, mainly through a better representation of the narrow straits in the Canadian Arctic Archipelago (CAA). The representation of CAA throughflow not only influences the release of water masses through the other gateways but also the circulation pathways inside the Arctic Ocean. However, the mean state and variability of Arctic freshwater content and the variability of freshwater transport through the Arctic gateways appear not to be very sensitive to the increase in resolution employed here. By highlighting the issues that are independent of model resolution, we address that other efforts including the improvement of parameterizations are still required. [ABSTRACT FROM AUTHOR]

Snow and ice over land are important hydrological resources and sensitive indicators of climate change. The Moderate Resolution Imaging Spectroradiometer (MODIS) dataset at 250-m spatial resolution generated at the Canada Centre for Remote Sensing (CCRS) is used to derive the annual minimum snow and ice (MSI) extent over the Canadian Arctic landmass over a 17-yr time span (2000-16). The smallest MSI extent (1.53 × 105 km2) was observed in 2012, the largest (2.09 × 105 km2) was observed in 2013; the average value was 1.70 × 105 km2. Several reanalyses and observational datasets are assessed to explain the derived MSI variations: the ERA-Interim reanalysis, North American Regional Reanalysis (NARR), Clouds and the Earth's Radiant Energy System (CERES) radiative fluxes, and European Space Agency's GlobSnow dataset. Comparison with the Randolph Glacier Inventory (RGI) showed two important facts: 1) the semipermanent snowpack in the Canadian Arctic that persists through the entire melting season is a significant component relative to the ice caps and glacier-covered areas (up to 36% or 5.583104 km2), and 2) the MSI variations are related to variations in the local climate dynamics such as warm season average temperature, energy fluxes, and snow cover. The correlation coefficients (absolute values) can be as high as 0.77. The reanalysis-based MSI estimates agree with satellite MSI results (average bias of 2.2 × 103 km2 or 1.3% of the mean value). [ABSTRACT FROM AUTHOR]

The Arctic is a global hotspot of climate change, which is impacting the livelihoods of remote Inuit communities. We conduct a longitudinal assessment of climate change vulnerability drawing upon fieldwork conducted in 2004 and 2015 in Ikpiarjuk (Arctic Bay), Nunavut, and focusing on risks associated with subsistence harvesting activities. Specifically, we employ the same conceptual and methodological approach to identify and characterize who is vulnerable, to what stresses, and why, assessing how this has changed over time, including re-interviewing individuals involved in the original study. We find similarities between the two periods, with many of the observed environmental changes documented in 2004 having accelerated over the last decade, exacerbating risks of land use: changing sea ice regimes and wind patterns are the most widely documented at both times, with new observations reporting more frequent sighting of polar bear and orca. Socio-economic and technological changes have altered the context in climate change impacts are being experienced and responded to, both exacerbating and moderating vulnerabilities compared to 2004. The adoption of new technology, including GPS and widespread use of the internet, has helped land users manage changing conditions while sharing networks remain strong, despite concern noted in the 2004 study that they were weakening. Challenges around access to financial resources and concern over the incomplete transmission of some environmental knowledge and land skills to younger generations continue to increase sensitivity and limit adaptive capacity to changing climatic conditions. [ABSTRACT FROM AUTHOR]

Adaptation readiness is proposed as a complimentary concept to adaptive capacity that captures the strength and existence of governance structures and policy processes which determine whether adaptation takes place. As such, adaptation readiness is concerned with examining actual experiences with planning for adaptation and seeks to characterize whether human systems are prepared and ready to 'do adaptation.' We propose a framework for evaluating readiness, identifying 6 overarching factors essential for adaptation taking place: political leadership, institutional organization, adaptation decision making and stakeholder engagement, availability of usable science, funding for adaptation, and public support for adaptation. For each readiness factor we identify potential indicators, data sources, and considerations for analysis, outlining approaches for quantitative scoring and qualitative examination. We briefly illustrate application of the framework using an example from the territory of Nunavut in the Canadian Arctic, a region projected to experience some of the most dramatic changes in climate globally this century. The framework provides a systematic approach for assessing adaptation readiness, and can be used - in combination with other approaches - to inform the identification and prioritization of adaptation support, guide resources to areas where need is greatest, and serve as a proxy for adaptation tracking. [ABSTRACT FROM AUTHOR]

Strong evidence for a pan-Arctic expansion of upright shrubs comes from analysis of satellite imagery, historical photographs, vegetation plots, and growth rings. However, there are still uncertainties related to local-scale patterns of shrub growth, resulting interactions among vegetation functional groups, and the relative roles of disturbance and climate as drivers of observed change. Here, we present evidence that widespread and rapid shrub expansion and lichen declines over a 15,000 km area of the western Canadian Arctic have been driven by regional increases in temperature. Using 30 m resolution Landsat satellite imagery and high resolution repeat color-infrared aerial photographs, we show that 85% of the land surface has a positive 1985-2011 trend ( P < 0.05) in NDVI, making this one of the most intensely greening regions in the Arctic. Strong positive trends (>0.03 NDVI/decade) occurred consistently across all landscape positions and most vegetation types. Comparison of 208, 1:2,000 scale vertical air photo pairs from 1980 and 2013 clearly shows that this greening was driven by increased canopy cover of erect dwarf and tall shrubs, with declines in terricolous lichen cover. Disturbances caused by wildfires, exploratory gas wells, and drained lakes all produced strong, yet localized increases in NDVI due to shrub growth. Our analysis also shows that a 4°C winter temperature increase over the past 30 years, leading to warmer soils and enhanced nutrient mineralization provides the best explanation for observed vegetation change. These observations thus provide early corroboration for modeling studies predicting large-scale vegetation shifts in low-Arctic ecosystems from climate change. [ABSTRACT FROM AUTHOR]

This study maps current understanding and research trends on the human dimensions of climate change (HDCC) in the eastern and central Canadian Arctic. Developing a systematic literature review methodology, 117 peer reviewed articles are identified and examined using quantitative and qualitative methods. The research highlights the rapid expansion of HDCC studies over the last decade. Early scholarship was dominated by work documenting Inuit observations of climate change, with research employing vulnerability concepts and terminology now common. Adaptation studies which seek to identify and evaluate opportunities to reduce vulnerability to climate change and take advantage of new opportunities remain in their infancy. Over the last 5 years there has been an increase social science-led research, with many studies employing key principles of community-based research. We currently have baseline understanding of climate change impacts, adaptation, and vulnerability in the region, but key gaps are evident. Future research needs to target significant geographic disparities in understanding, consider risks and opportunities posed by climate change outside of the subsistence hunting sector, complement case study research with regional analyses, and focus on identifying and characterizing sustainable and feasible adaptation interventions. [ABSTRACT FROM AUTHOR]

Mitochondrial DNA (mtDNA) sequences were analyzed from 106 bowhead whale ( Balaena mysticetus) specimens dating 471 ± 44 14C b.p.-10,290 ± 150 14C b.p. to evaluate whether historical changes in distribution and connectivity were detectable in levels of diversity and population structuring in the Central Canadian Arctic. The species has maintained levels of mtDNA diversity over 10,000 yr comparable to other nonbottlenecked large whale species. When compared to data from the Holocene East Greenland/Spitsbergen and contemporary Bering-Chuckchi-Beaufort populations, differentiation was low ( FST≤ 0.005, ΦST≤ 0.003) and no temporal or geographical genetic structuring was evident. A combination of analyses suggests that the population has expanded over the past 30,000 14C yr. This genetic signature of expansion could result from population growth, admixture of multiple gene pools, or a combination of both scenarios. Despite known climatic change that altered bowhead distribution and led to isolation of populations, there is no detectable population structuring or change in genetic diversity during the Holocene. This may be due to long generation time, occasional population connectivity and a historically large global population. These characteristics warrant caution when interpreting contemporary bowhead whale DNA data, as it is unlikely that any population will be in mutation-drift equilibrium. [ABSTRACT FROM AUTHOR]

An introduction to the journal is presented in which the editor discusses an articles on Northern Canada, climate change, and summary of the major findings and conclusions of the two assessments reports.

Copyright of Canadian Journal of Earth Sciences is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Killer whales ( Orcinus orca) have a global distribution, but many high-latitude populations are not well studied. We provide a comprehensive review of the history and ecology of killer whales in the Canadian Arctic, for which there has previously been little information. We compiled a database of 450 sightings spanning over 15 decades (1850-2008) to document the historical occurrence, distribution, feeding ecology, and seasonality of killer whales observed throughout the region. Sighting reports per decade increased substantially since 1850 and were most frequent in the eastern Canadian Arctic. The mean reported group size was 8.3 (median = 4, range 1-100), but size varied significantly among regions and observed prey types. Observations of predation events indicate that Canadian Arctic killer whales prey upon other marine mammals. Monodontids were the most frequently observed prey items, followed by bowhead whales ( Balaena mysticetus), phocids, and groups of mixed mammal prey. No killer whale sightings occurred during winter, with sightings gradually increasing from early spring to a peak in summer, after which sightings gradually decreased. Our results suggest that killer whales are established, at least seasonally, throughout the Canadian Arctic, and we discuss potential ecological implications of increased presence with declining sea ice extent and duration. [ABSTRACT FROM AUTHOR]

Aim The boreal tree line is a prominent biogeographic feature, the position of which reflects climatic conditions. Pollen is the key sensor used to reconstruct past tree line patterns. Our aims in this study were to investigate pollen-vegetation relationships at the boreal tree line and to assess the success of a modified version of the biomization method that incorporates pollen productivity and dispersal in distinguishing the tree line. Location Northern Canada (307 sites) and Alaska (316 sites). Methods The REVEALS method for estimating regional vegetation composition from pollen data was simplified to provide correction factors to account for differential production and dispersal of pollen among taxa. The REVEALS-based correction factors were used to adapt the biomization method and applied as a set of experiments to pollen data from lake sediments and moss polsters from the boreal tree line. Proportions of forest and tundra predicted from modern pollen samples along two longitudinal transects were compared with those derived from a vegetation map by: (1) a tally of 'correct' versus 'incorrect' assignments using vegetation in the relevant map pixels, and (2) a comparison of the shape and position of north-south forest-cover curves generated from all transect pixels and from pollen data. Possible causes of bias in the misclassifications were assessed. Results Correcting for pollen productivity alone gave fewest misclassifications and the closest estimate of the modern mapped tree line position (Canada, + 300 km; Alaska, + 10 km). In Canada success rates were c. 40-70% and all experiments over-predicted forest cover. Most corrections improved results over uncorrected biomization; using only lakes improved success rates to c. 80%. In Alaska success rates were 70-80% and classification errors were more evenly distributed; there was little improvement over uncorrected biomization. Main conclusions Corrected biomization should improve broad-scale reconstructions of spatial patterns in forest/non-forest vegetation mosaics and across climate-sensitive ecotones. The Canadian example shows this is particularly the case in regions affected by taxa with extremely high pollen productivity (such as Pinus). Improved representation of actual vegetation distribution is most likely if pollen data from lake sediments are used because the REVEALS algorithm is based on the pollen dynamics of lake-based systems. [ABSTRACT FROM AUTHOR]

Understanding the implications of climate change on northern Canada requires a background about the size and diversity of its human and biogeophysical systems. Occupying an area of almost 40% of Canada, with onethird of this contained in Arctic islands, Canada's northern territories consist of a diversity of physical environments unrivaled around the circumpolar north. Major ecozones composed of a range of landforms, climate, vegetation, and wildlife include: Arctic, boreal and taiga cordillera; boreal and taiga plains; taiga shield; and northern and southern Arctic. Although generally characterized by a cold climate, there is an enormous range in air temperature with mean annual values being as high as -5°C in the south to as low as -20°C in the high Arctic islands. A similar contrast characterizes precipitation, which can be >700 mm y-1 in some southern alpine regions to as low as 50 mm y-1 over islands of the high Arctic. Major freshwater resources are found within most northern ecozones, varying from large glaciers or ice caps and lakes to extensive wetlands and peat lands. Most of the North's renewable water, however, is found within its major river networks and originates in more southerly headwaters. Ice covers characterize the freshwater systems for multiple months of the year while permafrost prevails in various forms, dominating the terrestrial landscape. The marine environment, which envelops the Canadian Arctic Archipelago, is dominated by seasonal to multiyear sea ice often several meters thick that plays a key role in the regional climate. Almost two-thirds of northern Canadian communities are located along coastlines with the entire population being just over 100 000. Most recent population growth has been dominated by an expansion of nonaboriginals, primarily the result of resource development and the growth of public administration. The economies of northern communities, however, remain quite mixed with traditional land-based renewable resource-subsistence activities still being a major part of many local economies. [ABSTRACT FROM AUTHOR]

Northern Canada is projected to experience major changes to its climate, which will have major implications for northern economic development. Some of these, such as mining and oil and gas development, have experienced rapid expansion in recent years and are likely to expand further, partly as the result of indirect effects of changing climate. This article reviews how a changing climate will affect several economic sectors including the hydroelectric, oil and gas, and mining industries as well as infrastructure and transportation, both marine and freshwater. Of particular importance to all sectors are projected changes in the cryosphere, which will create both problems and opportunities. Potential adaptation strategies that could be used to minimize the negative impacts created by a climate change are also reviewed. [ABSTRACT FROM AUTHOR]

Many northern Canadians have continued a subsistence lifestyle of wildlife harvesting and, therefore, value sustainable wildlife populations. At a regional wildlife workshop in the Sahtu Settlement Area, Northwest Territories in 2002, elders and community leaders raised concerns regarding wildlife health, food safety, and the effects of climate change on wildlife. They requested that efforts be put toward training youth in science and increasing involvement of hunters and youth in wildlife research. In response, we initiated a long-term, integrated approach to foster community-based wildlife health monitoring and research. Annual trips were made to all schools in the Sahtu from 2003 to 2009 to provide hands-on learning for 250–460 students on a range of wildlife topics. In addition, interviews were conducted with 31 hunters and elders to document their local ecological knowledge of wildlife health and local hunters were trained as monitors to collect tissue samples and measurements to assess body condition and monitor health of harvested caribou ( n = 69) and moose ( n = 19). In 2007 the program was extended to include participation in the annual caribou hunt held by one community. Each year since 2005, a graduate student and/or a postdoctoral trainee in the veterinary or biological sciences has participated in the program. The program has evolved during the last 6 years in response to community and school input, results of empirical research, hunter feedback, local knowledge, and logistical constraints. The continuity of the program is attributed to the energetic collaboration among diverse partners and a unified approach that responds to identified needs. [ABSTRACT FROM AUTHOR]

The article presents the findings and conclusions on the climatic changes in regional assessment reports in Northern Canada. It notes that the climate of the Arctic has shown an unprecedented rate of change during the last 50 years. Over the last half century, the Canadian Arctic has experienced significant increases in both temperature and precipitation, consistent with trends in other circumpolar regions. It states that the greatest temperature increases observed over the western Arctic.

In Northern Canada, climate change has led to many acute and interrelated health and environmental impacts experienced among Inuit populations. Community-based monitoring, in which community members participate in monitoring initiatives using various forms of technology, is a key strategy increasingly used to detect, monitor and respond to climate change impacts. To better understand the landscape of existing environmental and health monitoring programmes mobilising different technologies and operating in the North we conducted a review that used environmental scan methodologies to explore and contextualise these programmes. We consulted with academic researchers with experience in community-led monitoring, conducted systematic searches of grey and peer-reviewed literature, and conducted a secondary search for environment-health mobile-phone applications. Following specific criteria, we identified 18 monitoring programmes using information and communication technologies in the North, and three global monitoring mobile-phone applications, which cumulatively monitored 74 environment and health indicators. Several themes emerged, including the need for: (1) community leadership, (2) indicators of environment and/or human health and (3) innovative technology. This synthesis supports the development of community-led, environment-health monitoring programmes that use innovative technology to monitor and share information related to the health implications of climate change in and around Indigenous communities throughout the Circumpolar North. [ABSTRACT FROM AUTHOR]