How will climate change impact Canada?

• Pacific Region
• Western Mountain Region
• Prairie Region
• Boreal Forest Region
• Great Lakes-St. Lawrence Region
• Atlantic Region
• Arctic Ocean Region
• National Parks and Wilderness Reserves

Pacific Region

	Photo: © Steve Hillebrand, USFWS

Climate change could impact dramatically on ecosystems in British Columbia and the Yukon:

• Higher air temperatures could bring drought to southern coastal and interior zones, cause landslides by melting glaciers and permafrost in northern and mountainous areas, reduce the flow of rivers and streams, make forests drier and more defenceless against pests, diseases, and fire, and imperil wildlife on land and in water.
• Warmer ocean temperatures could shift the ranges, spawning times, and food supplies of marine species like Pacific salmon, thereby depriving terrestrial species, like bears and bald eagles, of nourishment.
• Rising sea levels could threaten such coastal zones as the Fraser River delta with floods and erosion.
• Increasing rain and snow could cause flooding throughout the interior.

Western Mountain Region

	Photo: © Jacques Descloitres, MODIS

The Rockies' extremes of climate and altitude make them particularly prone to the effects of climate change:

• As temperatures rise, low-elevation glaciers are rapidly melting and may disappear or cause landslides that put wildlife habitat at risk. Plant and animal species are shifting upward, for example, sagebrush is replacing glacial meadows, and life forms restricted to the highest peaks are being displaced by others moving up from below.
• Increased precipitation means deeper snow, which could make it more difficult for animals like deer and elk to forage for food, and could rive them into valleys where they are more vulnerable to predator attacks and collisions with cars and trains.

Prairie Region

	Photo: © Erwin and Peggy Bauer, USFWS

The consequences of climate change in Canada's prairies could be severe:

• Rising temperatures, less rainfall, greater rates of evaporation and drier soils will mean habitat loss both on land and in water.
• Warmer weather may prolong the growing season and expand agriculture further north. It could also cause longer, more frequent droughts, diminished crop yields and the spread of desert-like conditions over part of the southern Prairies.
• Widespread fires in the boreal forest region may cause the northward expansion of grasslands and shrink the habitat of the woodland caribou and many other species.
• More than 50 percent of Prairie potholes could disappear. These ephemeral wetlands are key breeding habitats and migratory stopovers for Canadian ducks, including mallards, widgeons and pintails. Their loss would come as a brutal blow not only to waterfowl, but also to reptiles, amphibians and mammals.

Boreal Forest Region

	Photo: © Erwin and Peggy Bauer, USFWS

Scientists predict that this northern region — comprising one-third of the planet's forests — will be one of the areas most affected by climate change:

• Dry, warm weather could alter the ecosystem, making the forest fire season weeks longer, sparking more frequent and severe "monster blazes," and doubling the area burned each year. Rising temperatures could also result in more frequent and deadly attacks by forest pests, including spruce budworm and pine beetle.
• The species composition of the forest could change as conditions suitable for the growth and regeneration of pine, spruce, fir and other temperature-sensitive trees continue to shift.
• The timberline could move hundreds of kilometres further north, pushing the tundra back to the Arctic Islands and reducing it to one- to two-thirds its current size.
• As evergreen trees lose ground to hardwoods in the region's lower latitudes, losses from the southern margin of the forest will likely exceed the gains in the North.
• More than half of the boreal forest could vanish in the next hundred years because of climate change, imperilling boreal chickadees, pine martens, spruce grouse and countless other species whose survival depends on this vast ecosystem.

Great Lakes-St. Lawrence Region

	Photo: © iStockphoto.com/Stephen Strathdee

Climate change models predict major impacts on this region's lands and waters:

• Average temperatures could rise by 2 to 5 C while precipitation could increase by up to 25 percent by the end of this century.
• Expected changes on land include more days when heat stress and air pollution threaten the health of wildlife and humans, changes in forest composition due to shifting vegetation zones, increases in the frequency and severity of forest fires, the northward extension of agriculture, and a longer growing season. Significant declines in the populations of neotropical migratory birds, including many wood-warbler species, could result.
• As the region warms up, the temperatures of lakes, streams, and rivers will rise and much more water will evaporate. The levels of the Great Lakes and St. Lawrence River could fall by a metre in 30 years, reducing the volume of water that flows through the system and circulates oxygen to biologically productive zones.
• These changes will benefit some aquatic species and spell disaster for others. Cold-water fish, like salmon and trout, could lose both habitats and populations. Such species at risk as the spotted turtle and swamp rose mallow could see their habitats dry up while the nesting sites of waterfowl become more accessible to predators in Great Lakes marshes.

Atlantic Region

	Photo: © Jacques Descloitres, MODIS Rapid Response Team, NASA/GSFC

This region will be particularly vulnerable to rising sea levels and increased storm activity.

• Increased coastal erosion, sedimentation, flooding of low-lying habitats, shrinking of tidal flats and nesting beaches needed by shorebirds, and submersion of barrier islands vital to breeding raptors and colonial birds are among the effects of sea level rise.
• Salt marshes are particularly at risk. These coastal wetlands have adapted to a unique mix of fresh and salt water. Too much salinity could throw them off balance and harm the habitat of a wide range of species, particularly fish and waterfowl.
• Heavier rainfall would increase the volume of run-off polluting bays and estuaries that provide key stopovers for migratory bird sand nourish and feed countless species of molluscs, crustaceans, and fish.
• Changes in sea temperature would affect the ranges, distributions and food supplies of seabird and marine mammal populations.
• Heightened storm intensity, frequent fires and other ecological pressures would increase the dieback of coniferous trees and promote a transition from boreal to mixed and temperate forests.

Arctic Ocean Region

	Photo: © Susanne Miller

The far-reaching impacts of climate change will be felt nowhere more than in Canada's Arctic, one of the fastest-warming regions on Earth:

• As temperatures rise, climatologists anticipate not only the shrinking of the Arctic tundra, but also the shrinking of the Arctic sea ice. This frozen platform is integral to the lives of a huge array of species, such as walrus, seals and polar bears, that feed, travel and breed on its vast expanses. Algae living under the sea ice are the foundation of an ocean food chain that supports plankton, copepods, fish, seabirds and mammals. The average thickness of the sea ice has shrunk by 40 percent in the past three decades, jeopardizing the future of this web of life.
• Among the species most affected is the black guillemot, a seabird whose populations have plummeted since 1990. The melting of sea ice has increased the distances it must fly to forage for food.
• Likewise, the polar bear faces the loss of the frozen habitat it uses to hunt for ringed seals, its principal prey. As the climate gets warmer, the sea ice could break up several weeks earlier than normal in spring, reducing the time in which bears can fatten up prior to summer, when they usually fast. Unseasonable warmth could also cause the snow dens of ringed seals to collapse, reducing their pup's chances of survival and depriving polar bears of food. With lower body weight, mother bears will have more difficulty nursing their cubs. Biologists have already noticed a sharp decline in the birth rates of some populations and suspect that the physical condition of animals is worsening.

National Parks and Wilderness Reserves

	Photo: © USFWS

Scientific studies identify climate change as a danger to the health of our National Parks and Wilderness Reserves in six geographical regions. They forecast serious impacts on species surviving in "island" remnants of ecosystems already facing encroaching development, pollution and habitat fragmentation.

• Atlantic: Rising sea levels and consequent shrinking of tidal flats, coastal erosion and saltwater intrusion threaten national parks like Kouchibouguac and Cape Breton Highlands, and could damage the breeding and feeding habitats of migratory shorebirds. The cooling of the Labrador current, as result of the melting of Greenland's ice sheet, imperils the food supply of seabirds and whales off the coasts of Forillon and Terra Nova.
• Great Lakes - St. Lawrence: The dropping of water levels by more than a metre in the next 50 years could cause marshlands to dry up at Point Pelee, Bruce Peninsula and other parks, jeopardizing biodiversity. Rising temperatures and more frequent droughts could endanger many fish and plant species in La Mauricie.
• Prairies: Parks in this region will see some of the steepest temperature increases in Canada. Greater rates of evaporation and drought could affect not only fish and waterfowl, but also species at risk, like the burrowing owl and black-tailed prairie dog, in Grasslands National Park. Changes in the water levels of wetlands in Wood Buffalo National Park could seriously harm the breeding habitat of the endangered whooping crane.
• Western Cordillera: Warmer spring and fall temperatures in the southern Rockies could extend the melting season of glaciers by a month. Increasing winter precipitation in parks, such as Jasper, Yoho and Glacier, would mean deeper snow, impairing the movements and survival of elk, mountain goats and other animals.
• Pacific: A predicted 3.5 C increase in sea surface temperatures would have a severe impact on the coastal, marine and riverine waters of parks like Gwaii Haanas and Kluane. Warmer waters are already altering Pacific salmon spawning and migration routes. Deeper layers of snow and ice could affect food supplies of Dall sheep and mountain goats.
• Arctic: The region most threatened by climate change includes such parks as Aulavik and Wapusk, where winter temperatures could rise by as much as 10 C by mid-century. Arctic species, like polar bears, caribou and muskoxen, are already experiencing the effects of diminishing sea ice, shoreline erosion and shifting plant communities.