Impacts of recent extreme weather events highlight the vulnerability of Canadian communities and critical infrastructure to climate change.

The economic costs resulting from extreme weather events in Canada in the past decade (since 1996) have been greater than for all previous years combined. Costs reaching hundreds of millions and even billions of dollars are associated with flooding, wind, hail and ice storms, hurricanes, tornados and wild fires in all regions of southern Canada (Table SR-3), arising from property damage and disruption in the production and flow of goods and services. Prolonged periods of unusual weather, such as drought, can also result in high economic costs. Six of the ten most costly disasters in Canadian history have been droughts (Public Safety Canada, 2005). The national-scale drought of 2001–2002 resulted in Canada's gross domestic product being reduced by about $5.8 billion, as well as more than 41 000 job losses (Chapter 7). While it is not possible to attribute individual weather events to changing climate, such costs illustrate that Canadian communities and infrastructure are vulnerable to climate events. This vulnerability is likely to increase, since climate models project increases in the frequency and magnitude of many types of extreme weather (Chapters 2 and 9).

Table SR-3: Recent costly extreme weather events, excluding drought
(from Public Safety Canada, 2005; Environment Canada, 2005; BC Provincial Government, 2003).
Event and date Region Estimated costs Deaths Injuries Evacuations Relevant chapters
Ice storm, 1998 Ontario, Quebec, Atlantic Canada $5.4 billion 28 945 17 800 2, 4, 5, 6
Saguenay flood, 1996 Quebec $1.7 billion 10 0 15 825 2, 5
Calgary hailstorm, 1991 Prairies $884 million 0 0 0 2, 7
Red River flood, 1997 Prairies $817 million 0 0 25 447 2, 7
BC/Alberta wildfires, 2003 British Columbia $700 million 3 unknown 45 000 7, 8
Toronto extreme rain, 2005 Ontario >$500 million 0 0 unknown 6
Southern Alberta floods, 2005 Prairies >$400 million 4 unknown >2000 7
Calgary hailstorm, 1996 Prairies $305 million 0 0 0 2, 7
Hurricane Juan, 2003 Atlantic Canada $200 million 8 unknown unknown 2, 4

Extreme weather events affect the health and well-being of Canadians, as they frequently involve job losses, loss of assets, displacements, physical injuries and illnesses, psychological disorders, and loss of lives. The 1998 ice storm resulted in 945 injuries, while wildfires in British Columbia and Alberta resulted in an estimated 45,000 displacements in 2003, both of which are records for natural disasters in Canada (Table SR-3). Heavy rainfall following a period of drought was a contributing factor to the E. coli outbreak in Walkerton, Ontario in 2000, which resulted in seven deaths and thousands of people becoming ill (Chapter 6).

Adaptive capacity in Canada is generally high but is unevenly distributed between and within regions and populations.

As a prosperous country with high levels of education, access to technology, and strong and effective institutions, Canada is well positioned to take action on adapting to climate change (Chapter 10). However, there are significant differences in this ability to adapt among different subregions and population groups, resulting in differing vulnerabilities to climate change (Box SR-3). Indeed, the IPCC AR4 has concluded that, in all regions of the world, no matter how prosperous, there are certain areas, sectors and communities that are particularly vulnerable to climate change (Wilbanks et al., 2007).

BOX SR-3: Vulnerability and adaptive capacity

Vulnerability to climate change “is the degree to which a system is susceptible to, and unable to cope with, adverse effects of climate change, including climate variability and extremes” (Intergovernmental Panel on Climate Change, 2007, p. 21). Three factors influence the vulnerability of any system: 1) the nature of the climate changes to which it is exposed; 2) the climate sensitivity of the system; and 3) the capacity of that system to adapt to changed climate conditions. Therefore, while a sector, community or population may be exposed to significant climate changes, it is not considered vulnerable unless those climate changes result in significant negative impacts, and it does not have the capability to undertake adaptation actions that would significantly reduce those impacts.

Although extensive research efforts have focused on projecting the magnitude and rate of climate changes, and on understanding the relationships between climate and biophysical systems, the characterization of adaptive capacity is a relatively new area of study. Adaptive capacity is influenced by a number of location-specific social, economic and institutional factors that act to either constrain or enhance the ability to adapt.

Within Canada, there are significant differences in the climate sensitivity of major economic sectors. Among the most sensitive sectors are those dependent upon renewable natural resources, including agriculture, fisheries, forestry and non-commercial food supply, as well as many aspects of tourism and recreation. Adaptive capacity similarly varies widely between sectors, communities and populations. Assessment of vulnerability must consider variability in all these factors.

Since vulnerability refers to the susceptibility of a system to harm, it does not consider the benefits that may result from changing climate. However, the ability to take advantage of such opportunities is also a function of adaptive capacity. Finally, where vulnerability is considered relatively low due to a high capacity to adapt, significant negative impacts may still occur if appropriate adaptation actions are not implemented. As noted in the IPCC AR4, although many societies have high adaptive capacity and the necessary financial resources, they have not taken effective action on adaptation to climate change, variability and extremes (Adger et al., 2007; Field et al., 2007)

Within Canada, differences in adaptive capacity and the perception of the risks presented by climate change have been noted between urban centres and rural/remote communities (Chapters 4–7). Both urban and rural centres have characteristics that enhance or limit adaptive capacity (Table SR-4). Urban centres tend to be places of greater wealth, higher education and skill sets, with easier access to technology and institutions. However, urban centres also tend to have greater reliance on critical energy, transportation and water infrastructure, more severe heat stress and air quality problems, and larger numbers of poor and elderly residents that result in vulnerabilities not shared by most rural communities (Chapters 5 and 6). Northern Canada, with its sparse, widely distributed population, evolving governance and institutions, and significant subsistence economy, has unique limitations to adaptive capacity (Chapter 3). Among population groups, the poor, the elderly, recent immigrants and Aboriginal peoples tend to face greater challenges in coping with climate changes, often due to limited financial resources, health problems and difficulties accessing technology and institutional services (Chapters 2–9).

Table SR-4: General differences in adaptive capacity, which affect vulnerability to climate change, between urban and rural communities (note that these do not apply in all cases; Chapters 3, 6, 7 and 8)
Urban centres Rural communities
Greater access to financial resources Strong social capital
Diversified economies Strong social networks
Greater access to services (e.g. health care, social services, education) Strong attachments to community
Higher education levels Strong traditional and local knowledge
Well-developed emergency response capacity High rates of volunteerism
Highly developed institutions  
Higher costs of living Limited economic resources
More air quality and heat stress issues Less diversified economies
Lack of knowledge of climate change impacts and adaptation issues Higher reliance on natural resource sectors
High dependence on potentially vulnerable electricity grid Isolation from services and limited access
Aging infrastructure Lower proportion of population with technical training
Issues of overlapping jurisdictions can hinder decision-making ability  

Resource-dependent and Aboriginal communities are particularly vulnerable to climate changes. This vulnerability is magnified in the Arctic.

Although agriculture, forestry, fishing and hunting do not account for a large percentage of Canada's GDP, they are vitally important for the economic well-being of many subregions and communities where land- and resource-based activities remain the foundation of economic life. More than 1600 communities in all regions of Canada obtain 30% or more of their employment income from these sectors. The economic impacts of climate change at the community scale can be significant (Chapter 2). The vulnerability of resource-dependent communities to climate change reflects the high climate sensitivity of many natural resource–based industries, limited economic diversification, and more restricted access to services (Chapters 2–8).

Aboriginal communities, many of which retain strong linkages to the land for both economic and cultural well-being, are also particularly vulnerable to climate change impacts (Ch 3–8). The subsistence economy may constitute up to 50% of the total income in these communities (Chapter 2). This vulnerability is magnified in Arctic regions, where rates of warming have been, and are projected to be, the greatest in the world. Changes in snow cover and sea-ice conditions, along with ecosystem impacts, are affecting access to traditional food supplies, while permafrost degradation and coastal erosion are affecting community infrastructure (Chapter 3). The adaptive capacity of many Aboriginal communities is presently being eroded by social, cultural, political and economic changes taking place in response to a range of stresses (Chapter 3). Significant impacts on traditional ways of life are unavoidable (Chapters 3, 4, 5, 7 and 8).