The impacts of changing climate are already evident in Canada and globally. Climate change will continue for many decades, and even centuries, regardless of the success of global initiatives to reduce greenhouse gas emissions (mitigation). Adaptation is a necessary complement to mitigation in addressing climate change (Figure SR-1). Adaptation involves making adjustments in our decisions, activities and thinking because of observed or expected changes in climate, with the goals of moderating harm and taking advantage of new opportunities (Box SR-1). The fourth assessment report of the Intergovernmental Panel on Climate Change (IPCC AR4) states that, while neither adaptation nor mitigation actions alone can prevent significant climate change impacts, taken together they can significantly reduce risks. It further states that there is no optimal mix between adaptation and mitigation, and that climate change policy is not about making choices between the two. Mitigation is necessary to reduce the rate and magnitude of climate change, while adaptation is essential to reduce the damages from climate change that cannot be avoided (Intergovernmental Panel on Climate Change, 2007; Klein et al., 2007).
In this report the term 'climate change' refers to any change in climate over time, whether it is the product of natural factors, human activity or both. This usage is the same as that of the Intergovernmental Panel on Climate Change, but it differs from the usage in the United Nations Framework Convention on Climate Change, which restricts the term to climate changes that can be directly or indirectly related to human activity and is additional to natural climate variability. The term 'changing climate' is used sometimes in this report to highlight that these changes are ongoing.
This synthesis of From Impacts to Adaptation: Canada in a Changing Climate 2007 presents conclusions regarding current and future impacts of, and vulnerabilities to, climate change in Canada. It also discusses adaptation actions being taken now to reduce risks and take advantage of opportunities associated with changing climate, and those that could be undertaken in future. Although the identification of specific priority issues for policy and program action requires analyses beyond the scope of this scientific assessment, the conclusions of this assessment do provide input into that detailed analysis. The synthesis is based on information contained within the individual chapters of the report — particularly Chapters 3 through 8, which present regional analyses for the North, Atlantic Canada, Quebec, Ontario, the Prairies and British Columbia, and Chapter 9, which examines the implications for Canada of climate change impacts and adaptation elsewhere in the world. The key findings of these chapters are summarized in Box SR-2. The remainder of the synthesis provides an integrative analysis of that information at a national scale. As appropriate, the conclusions are linked to findings of the IPCC AR4, demonstrating that the challenges that climate change adaptation presents to Canada are shared with other countries and regions, and that there is a great deal to be learned through the sharing of adaptation experiences.
BOX SR-1: What is adaptation to climate change?
Adaptation to climate change is any activity that reduces the negative impacts of climate change and/or positions us to take advantage of new opportunities that may be presented. Adaptation includes activities that are taken before impacts are observed (anticipatory) and after impacts have been felt (reactive; Table SR-1). Both anticipatory and reactive adaptation can be planned (i.e. the result of deliberate policy decisions), whereas reactive adaptation can also occur spontaneously. In most circumstances, anticipatory planned adaptations will incur lower long-term costs and be more effective than reactive adaptations.
|Based on||Type of adaptation|
|Timing (relative to climate impact)||Reactive||Concurrent||Anticipatory|
|Temporal scope||Short term||Long term|
Adaptation will usually not take place in response to climate change alone, but in consideration of a range of factors with the potential for both synergies and conflicts. Successful adaptation does not mean that negative impacts will not occur, only that they will be less severe than would be experienced had no adaptation occurred. In deciding what adaptation option is most appropriate for a particular situation, attention must be paid to the feasibility, likelihood and mechanisms for uptake.
BOX SR-2: Summary of chapter key findings
NORTHERN CANADA (Chapter 3)
- Current levels of exposure to, and sensitivity to, climate-related changes, as well as limitations in adaptive capacity, make some northern systems and populations particularly vulnerable to the impacts of climate change.
- Climate-induced changes in permafrost, sea ice, lake ice and snow cover have large implications for infrastructure maintenance and design.
- Climate changes will result in shifts in species availability, accessibility and quality, with consequences for biodiversity and human populations that rely on these resources.
- Increased navigability of Arctic marine waters and expansion of land-based transportation networks will bring both opportunities for growth in a range of economic sectors and challenges associated with culture, security and the environment.
- Maintaining and protecting aspects of traditional and subsistence ways of life in many Arctic Aboriginal communities will become more difficult in a changing climate.
ATLANTIC CANADA (Chapter 4)
- Changing climate will result in more storm events, increasing storm intensity, rising sea level, higher storm surges, coastal erosion and flooding, affecting coastal communities and their infrastructure and industries.
- Water resources will come under increasing pressure as conditions shift and demands change in response to both climatic and non-climatic factors.
- Impacts on marine fisheries will extend beyond fish species to include numerous aspects of fishery operations, such as transportation, marketing, occupational health and safety, and community health and well-being.
- Although higher temperatures and longer growing seasons could benefit agriculture and forestry, associated increases in disturbances and moisture stress pose concerns.
- Vulnerability of Atlantic communities can be reduced through careful planning, especially in coastal regions and through adaptation focused on limiting exposure to sea-level rise.
QUEBEC (Chapter 5)
- The largest changes in climate in this region are anticipated to occur in Arctic Quebec, exacerbating existing problems relating to natural disasters and critical infrastructure, and challenges in maintaining traditional ways of life.
- Climate change impacts on the natural environment will adversely affect ecosystem health, and have especially significant consequences where natural resources are a key component of the economy. Some impacts could be beneficial for certain economic sectors, including hydroelectricity and forestry.
- In the maritime region, there will likely be increased shoreline erosion along the Gulf of St. Lawrence and the St. Lawrence River estuary, where most of the region's social and economic activity is concentrated.
- In southern Quebec, an increase in the frequency, intensity or duration of extreme weather conditions would increase risks for the aging built environment, vulnerable populations and communities in areas exposed to natural hazards.
- Adaptation offers many possible solutions for reducing adverse impacts. Quebec's increasingly diversified knowledge economy provides a high degree of adaptive capacity. Little is generally known about the costs and limitations of adaptation, particularly in the long term.
ONTARIO (Chapter 6)
- Climate-related disruptions to critical infrastructure, including water treatment and distribution systems, energy generation and transmission, and transportation have occurred throughout the province and are likely to become increasingly frequent in future.
- Water shortages have been documented in southern regions of the province, and are projected to become more frequent as summer temperatures and evaporation rates increase.
- Climate-related events, such as extreme weather, heat waves, smog episodes and ecological changes that support the spread of vector-borne diseases, all present risks to the health of Ontario residents.
- Remote and resource-based communities have been severely affected by climate-related events that have caused repeated evacuations, disrupted vital transportation links and stressed forest-based economies. The impacts are expected to increase in future.
- Ontario's ecosystems are currently stressed by the combined influence of changing climate, human activities and natural disturbances.
Ontario has a strong capacity to adapt to climate change; however, this capacity is not uniform across the region and between sectors.
PRAIRIES (Chapter 7)
- Increases in water scarcity represent the most serious climate risk in the Prairie Provinces.
- Ecosystems will be impacted by shifts in bioclimate, changes in fire and insect disturbances, stressed aquatic habitats and the introduction of non-native species, with implications for livelihoods and economies dependent on ecological services.
- The Prairies are losing some advantages of a cold winter. Cold winters limit pests and diseases, facilitate winter operations in the forestry and energy sectors, and provide access to remote communities through the use of winter roads.
- Communities dependent on agriculture and forestry are highly sensitive to climate variability and extremes. Drought, which can have associated economic impacts of billions of dollars, wildfire and severe floods are projected to occur more frequently in future.
- Adaptive capacity, though high, is unevenly distributed, resulting in differing levels of vulnerability within the region.
- Although adaptation processes are not well understood, institutions and civil society will play a key role in mobilizing adaptive capacity by building on several recent examples of initiatives that enhance resilience.
BRITISH COLUMBIA (Chapter 8)
- Many regions and sectors of British Columbia will experience increasing water shortages and increasing competition among water uses (e.g. hydroelectricity, irrigation, communities, recreation and in-stream flow needs), with implications for transborder agreements.
- The increasing frequency and intensity of extreme weather and related natural hazards will impact critical infrastructure, affecting communities, industries and the environment.
- British Columbia's forests, forest industry and forest-dependent communities are particularly vulnerable to climate-related risks, including pest infestations and fire.
- Climate change will exacerbate existing stresses on British Columbia's fisheries. The vulnerability of Pacific salmon fisheries is heightened by the unique social, economic and ecological significance of these species.
- British Columbia's agricultural sector faces both positive and negative impacts from climate change, with more frequent and sustained drought being the greatest risk.
- Integrating climate change adaptation into decision-making is an opportunity to enhance resilience and reduce the long-term costs and impacts of climate change.
CANADA IN AN INTERNATIONAL CONTEXT (Chapter 9)
- Climate change is already affecting the residents, economies and environments of all regions of the world. These impacts, which are primarily related to extreme climate events and changes in water resources, are mostly adverse and are expected to continue and intensify in the future.
- Diseases currently prevalent in warmer climates will become greater threats in Canada as a result of greater incidence of disease and vectors in countries that are involved in trade and travel with Canada.
- The impacts of climate change and the adaptation measures that other countries take to respond to them can affect Canada in a number of ways, with potentially significant implications for trade, health, tourism, disaster relief, development aid and peace-keeping.
- As a developed country, increasing demands will be placed on Canada to support disaster relief efforts and to help developing countries adapt to climate change.