These two circulation phenomena result in alternating warm periods and , accompanied by a deeper Aleutian Low, and a cool period in the eastern North Pacific. These major fluctuations and longer term warming trends appear to both be at work, reinforcing each other in warm phases.
At the same time, with the frequency of intense winter storms in parts of the Northern Hemisphere increasing McCabe et al. From to , significant wave heights have increased about 1 cm per decade off British Columbia's coasts Gulev and Grigorieva, Such increases are projected to continue Caires et al.
Sea-level rise and an increase in intense storms are resulting in flooding and erosion episodes and related water quality problems on the west coast, especially in the lower mainland see Chapter 8. With continued warming of the eastern North Pacific, the population distribution for sockeye salmon will be compressed, forcing them increasingly into the Bering Sea Welch et al.
Figure 6 shows the current thermal limits for sockeye salmon in December upper panel and July lower panel. While it is expected that changes in total numbers may be small, changes in regions of occurrence will mean that a particular species will be caught by fishers from different countries.
For anadromous fish, warming water in spawning rivers may also change the populations and ranges of certain fish stocks see Chapter 8. Aquaculture in coastal waters could benefit from warmer conditions, with increased growth rates and an increase in the geographic range of the activity.
Higher water temperatures and related physical changes could, however, result in more intense and frequent disease outbreaks and algal blooms Kent and Poppe, Bacterial contamination of oysters and other shellfish may be more frequent as water temperatures rise.
The increased frequency of intense winter storms and the trend towards higher wave heights would also physically endanger aquaculture operations. Fishers would be affected in several ways by the changing climate. They may need to go farther from home ports to catch their quota of a particular species.
This exposes them to increasing hazards from the more frequent intense winter storms and higher waves off the west coast. In addition to such safety concerns, the changing fish populations may make it necessary to adapt by modifying the kinds of fish they catch and where they catch them Beamish et al. Tourism in western coastal waters will be affected in similar ways. Generally, small recreational boats would require greater attention to safety because of higher waves and greater incidence of severe storms.
Sea-level rise and severe storms would also have negative effects on marinas and other coastal infrastructure used for fisheries and boating, which may require expensive adaptation measures to maintain see Chapter 8.
Although the most favourable ship routings across the Pacific may change as circulation, winds and storm patterns change, the main impact on shipping is likely to be through ports and shore infrastructure.
In British Columbia, reinforcement and raising of breakwaters and wharves will likely be required to adapt to higher water levels and the greater wave regime, to ensure that Canadian ports remain internationally competitive see Chapter 8. Little international shipping takes place in the Canadian Arctic at present.
Port and docking facilities in the Canadian Arctic are rudimentary, with the exception of the Port of Churchill, Manitoba, on Hudson Bay, which has four deep-sea berths for grain, general cargo and tanker vessels. In , Manitoba and the Russian province of Murmansk -the European gateway to the Northeast Passage-signed a letter of intent to develop a marine link between the two provinces. Dubbed the 'Arctic Bridge', this concept is to develop further the Port of Churchill as part of a North American trade corridor.
This concept is deemed viable as a result of the longer sea ice -free shipping season in Hudson Bay and the Davis Strait. It has been suggested that there should be development of port facilities at Iqaluit to assist regional economic growth Aarluk Consulting Inc. The duration of ice cover in the Canadian Arctic Archipelago is projected to be reduced by one month by and by two months by Dumas et al.
However, there would still be significant ice hazards for ship transits see Chapter 3. Base-metal mines, including the Polaris lead-zinc on Little Cornwallis Island and the Nanisivik zinc mine on northern Baffin Island, were supplied by sea, and concentrate was shipped to smelters in Europe and elsewhere.
However, these mines ceased operations in and , respectively, leaving the Raglan nickel-copper mine in northern Quebec and the prospect of a huge nickel mine at Voisey's Bay in Labrador to be serviced by sea. The mining industry hopes to develop port and road facilities in or near Bathurst Inlet to service and supply exploration and development operations for precious and base metals and diamonds in the Kitikmeot region and northern Northwest Territories see Chapter 3.
A considerable increase in international use of the Canadian portion of the Arctic Ocean seems likely. Further, the ACIA suggested that trans-Arctic shipping during the summer is likely to be feasible within decades.
Diminished sea ice in summer in the Canadian Arctic could prompt the world's shipping community to seek expanded access to the Northwest Passage Figure 7 to convey international cargos, taking advantage of the shorter sea route from eastern Asia and the west coast of North America to the eastern seaboard of North America and western Europe.
Most climate models suggest that these sea ice changes will occur in the latter half of this century Walsh et al. Do two oceans boarder Canada? Which country and which oceans border Alaska? The Atlantic coast of Canada in Newfoundland and Labrador. Historically, there are four oceans; Pacific, Atlantic, Indian, and Arctic. List the countries that border 3 oceans? The planet currently has five defined oceans. Great Plains, with rolling prairie; deeply incised rivers; water-filled depressions called sloughs ; dry streambeds called coulees ; and, in the drier areas, mesas, buttes, and badlands.
To the south and southeast of the Shield lies a triangular, flat, and fertile plain bounded by Georgian Bay in Lake Huron, the St. Lawrence River, and Lake Ontario. Grasslands made up of many different types of stunted bushes and grasses extend over much of the southern Canadian Great Plains. The Tundra is situated on the northern Canadian Shield. This is an area of Precambrian rock with moss-covered, frozen subsoil.
Low-growing grasses and small bushes thrive in this arctic region. Between the northern tundra and the southern grassland is the boreal forest. Canada's great boreal forest is the largest of its woodlands, occupying 35 percent of the total Canadian land area and 77 percent of Canada's total forest land.
Named for the Greek god of the north wind, Boreas, this forest constitutes a band 1, kilometers miles wide. The boreal forest is characterized by the predominance of coniferous trees, which first sprung up during the Miocene Epoch, twelve to fifteen million years ago; today, this forest is an important source of paper products, jack-pine railway ties, and logs. Canada possesses 24 percent of the world's wetlands, covering more than million hect-ares million acres.
Most of the wetlands are located in the boreal peat bogs in arctic and sub-arctic regions, or in the Prairie pothole region across south-central Canada and the northern United States, which contains more than four million wetlands and ponds. The principal mountainous region is the Western Cordillera or Cordilleran Mountain system located in the westernmost portion of Canada.
The Cordilleran range, commonly known as the Canadian Rockies, is composed of relatively young, folded, and faulted mountains and plateaus. The chain is much narrower than the Rocky Mountains in the United States, with less extensive interior plateaus. The individual summits, however, are much higher in Canada, and they contain some of the most beautiful scenery in the world, with magnificent forests of alpine fir, Engelmann spruce, lodgepole pine, aspen, and mountain hemlock.
Most peaks in the Canadian Rockies exceed elevations of 4, meters 14, feet ; twenty-four summits top 4, meters 13, feet. Elias Mountains of the Yukon Territory. The only other parts of Canada with comparable spectacular mountains are Baffin and Ellesmere Islands in the northeastern Arctic Ocean.
The highest point in Quebec is Mont D'Iberville, at 1, meters 5, feet , within the Torngat range. The Appalachian Chain crosses parts of eastern Canada. In the Appalachians, the highest peak is Mont Jacques-Cartier, at 1, meters 4, feet. Canada has caves in nearly every region. Vancouver Island is commonly called the "Island of Caves" because of the large number of caves located there, many of which have not been explored. It runs about 20, meters 66, feet long and about meters 1, feet deep.
Banff National Park also contains the Cave and Basin, an area which boasts naturally occurring warm mineral springs. The discovery of the cave in prompted the government to choose the site as the center of its first national park, making the cave a national historic site as well as a protected area. Arctomys Cave, in the Canadian Rockies of British Columbia, is the deepest cave in the country and one of the deepest in North America north of Mexico.
It has a depth of meters 1, feet. The most prominent geographic feature in the country is the Canadian Shield sometimes called the Precambrian Shield or the Laurentian Plateau , which takes up almost half of Canada's total area. It extends beyond the Canadian boundary into the United States in two limited areas: at the head of Lake Superior and in the Adirondack Mountains.
Structurally, the shield may be thought of as a huge saucer, the center of which is occupied by Hudson Bay and James Bay, which have breached the northeastern rim to drain into the Atlantic Ocean through the Hudson Strait. Most of the shield is relatively level and less than meters 2, feet above sea level.
The earth's magnetic poles represent the two nearly opposite ends of the planet where the earth's magnetic intensity is the greatest. Only along the dissected rim of the saucer are there major hills and mountains: the Torngat Mountains. Except for the plains, the rest of the shield is composed of undulating terrain with rocky, knoblike hills; lakes interconnected by rapidly flowing streams occupy the hollows between these hills.
A second and far less extensive plateau supports the Western Cordillera. As of , the Syncrude Tailings Dam in Alberta was the largest in the world, based on the total amount of building material used in its construction.
It is a barrage dam, created from piled-up dirt and residue or tailings left over from mining operations at Syncrude Canada Ltd. The Gardiner Dam in Saskatchewan is the twelfth-largest water-retaining dam in the world. Hydroelectric power from this dam is used across the province. After acquiring the land security, the attention was diverted to the north-western passage which was considered as a strait for international navigation through Canadian territorial waters by United States and European Union.
But Canada asserted the passage to be internal waters over which it has full jurisdiction and control. Finally, in , Canada and the United States concluded an Arctic Co-operation Agreement through which future transits through the passage by icebreakers would be undertaken with the consent of Canada.
This project also measured water circulation timescales in the Arctic and samples were taken for nuclear traces.
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