Introduction - Northern Canada

There is strong evidence from scientists and local residents that Canada's North is already experiencing changes in its climate (e.g. Ouranos, 2004; Huntington et al., 2005; McBean et al., 2005; Overpeck et al., 2005; Bonsal and Prowse, 2006). The western and central Canadian Arctic experienced a general warming during the past 50 years of approximately 2 to 3 °C (Zhang et al., 2000). In the eastern Canadian Arctic, cooling of approximately 1 to 1.5 °C occurred during the same period (Zhang et al., 2000), but with warming reported in the last 15 years. Local Aboriginal hunters and elders have reported significant warming throughout the region in recent decades, which corroborates the scientific observations (e.g. Huntington et al., 2005; Nickels et al., 2006). These climatic changes have resulted in significant decreases in the extent and thickness of sea ice in some parts of the Arctic, thawing and destabilization of permafrost terrain, increased coastal erosion, and shifts in the distribution and migratory behaviour of Arctic wildlife species (Arctic Climate Impact Assessment, 2004, 2005). Climate model projections suggest that these recently observed changes across the North will continue (Kattsov et al., 2005; Bonsal and Prowse, 2006), with a myriad of implications for human and wildlife populations and future regional development (Arctic Climate Impact Assessment, 2004, 2005; Ford et al., 2006b; Furgal and Seguin, 2006).

A number of recent scientific assessments have examined changes in climate and in socioeconomic, environmental and political conditions, and the impacts of these changes on Arctic regions (e.g. Intergovernmental Panel on Climate Change, 2001a, b, 2007a, b; Arctic Monitoring and Assessment Program, 2002; Arctic Climate Impact Assessment, 2004, 2005; Einarsson et al., 2004; Chapin et al., 2005). These works provide a strong foundation for evaluating the impacts of climate change on the services that the Arctic environment provides to local, regional and national populations and economies, and the vulnerabilities of human systems to change. This chapter builds on these previous assessments and adopts aspects of a vulnerability approach to climate assessment, primarily through a review of existing and projected exposures and adaptive capacity (see Chapter 2). In so doing, it moves towards a more comprehensive understanding of climate impacts and adaptation across the northern regions of the country.

In the context of this chapter, Northern Canada refers to the three territorial administrative regions (Yukon, Northwest Territories and Nunavut) north of latitude 60 °N in Canada. Although these areas share many biogeographic characteristics, each has unique environmental, socioeconomic, cultural and political characteristics. Together, they form a vast region encompassing nearly 60% of Canada's landmass and many ecological zones, and feature nearly 100 communities of diverse languages and cultures (Figure 1). Sections 1 and 2 of this chapter provide an introduction to climate change in the Canadian Arctic, a review of past and current conditions, and projections for future climate in the North. Section 3 discusses the impacts that climate change is expected to have on key components of the Arctic environment, many of which are the basis for livelihoods in northern communities. Section 4 discusses the implications of these changes for regional and national services, with a focus on identifying specific vulnerabilities of various sectors and systems. Section 5 then addresses implications for large and small northern communities, and provides perspectives from potentially vulnerable populations, such as Arctic Aboriginal groups. Finally, key conclusions are presented in Section 6.

Text version - Figure 1

Map of the Canadian North demonstrating political boundaries as well as permafrost zones. The colour coding on the map corresponds to either continuous, extensive discontinuous, sporadic, isolated, mountain or known subsea zones. Stars on the map represent communities. The extreme north is primarily continuous permafrost with a known subsea present at the northern extreme of the Yukon, in Sachs Harbour. Extensive discontinuous, sporadic, isolated and mountain zones are respectively present from North to South in the northern halves of the provinces. The Rockies and Coastal mountains are depicted as Mountain permafrost zones.

This chapter draws on a number of different sources and methods to assess the current and potential future impacts of climate change across Northern Canada (see also Chapter 2). For topics presented in Sections 1 to 3, the chapter relies primarily on review and assessment of the published scientific literature. Where appropriate, authors have drawn on government reports and other ‘grey' literature sources. For many of the topics presented in Sections 4 and 5, scientific research in the Arctic is still underway or just in its initial stages. As a result, these sections rely more heavily on grey literature and on documentation of local observations and traditional knowledge, and on the expert judgement of the assessment team.