Geography of the Yukon

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A map of Yukon
A map of Yukon

The Yukon Territory is in the northwestern corner of Canada. The sparsely populated territory abounds with natural scenic beauty, with snowmelt lakes and perennial whitecapped mountains, including many of Canada's highest mountains. Although the climate is arctic and subarctic and very dry, with long cold winters, the long sunshine hours in the short summer allow a profusion of flowers and fruit to blossom. Most of the territory is boreal forest, tundra being the main vegetation zone only in the extreme north and at high elevations. The world's largest non-polar icefield, the Kluane icefields is mostly in the Yukon.

The territory is about the shape of a right triangle, bordering the American state of Alaska to the west, the Northwest Territories to the east and British Columbia to the south. The Yukon covers 482,443 square kilometres, of which 474,391 km² is land and 8,052 km² is water.




It is bounded on the south by the 60th parallel of latitude. Its northern coast is on the Beaufort Sea. Its western boundary is 141 degrees west longitude. Its ragged eastern boundary mostly follows the divide between the Yukon River Basin and the Mackenzie River watershed to the east in the Mackenzie mountains. All of the Yukon is west of Vancouver, British Columbia and contains Canada's westernmost communities.

Contents

[edit] Physical Geography

Except for the coastal plain on the Beaufort Sea (Arctic Ocean) coast, most of the Yukon is part of the American cordillera. The terrain includes mountain ranges, plateaus and river valleys.

The southwest is dominated by the Kluane icefields in Kluane National Park and Reserve, the largest non-polar icefields in the world. Kluane National Park also contains eight of Canada's ten highest mountains, including the five highest, all in the Saint Elias Mountains. A number of glaciers flow out of the icefields, including the Logan Glacier, the Hubbard Glacier and the Kaskawulsh Glacier.

Permafrost is common. The northern part of the territory has continuous permafrost, while it is widespread in the central part. Even the southern Yukon has scattered patches of permafrost.

Two major faults, the Denali fault and the Tintina fault have created major valleys called trenches: the Shakwak trench and the Tintina trench. The Shakwak trench separates the Kluane ranges from other mountain ranges north of it. The Haines Highway and the Alaska Highway north of Haines Junction are built in the Shakwak trench. The Tintina trench bisects the Yukon from northwest to southeast and its edges have rich mineral deposits including the Klondike gold and the lead-zinc deposits near Faro.

Sources: Yukon Geological Survey, Yukon Geoprocess File User Guide (PDF file, 1.2MB)

[edit] Volcanoes

The volcanoes in the Yukon are part of the circle of volcanoes around the Pacific Ocean known as the Pacific Ring of Fire. The Yukon includes more than 100 separate volcanic centers that have been active during the Quaternary. The Fort Selkirk Volcanic Field in central Yukon is the northernmost Holocene volcanic field in Canada, including the young active cinder cone, Volcano Mountain. A volcanic field in southcentral Yukon is called Alligator Lake. It contains two well-preserved cinder cones that caps a small shield volcano. Lava from the cones traveled north and were erupted at the same time. Volcanoes in southwestern Yukon are part of the Wrangell Volcanic Field, which is related to the subduction of the Pacific Plate beneath the North American Plate at the easternmost end of the Aleutian Trench.

Yukon volcanoes include:

[edit] Mountain Ranges

The Saint Elias mountains are part of the Coast Mountains which range from southern British Columbia to Alaska and cover the southeastern Yukon. While the Saint Elias Mountains contain the highest mountains, there are numerous other mountain ranges, from the British Mountains in the far north, which are part of the Brooks Range, to the Mackenzie Mountains and the Richardson Mountains in the east, the Cassiar Mountains in the south-east, the Pelly Mountains in the central Yukon, and the Ogilvie Mountains north of Dawson City and along the Dempster Highway.

Yukon mountain ranges include:

[edit] Highest Mountains

Highest Mountains in the Yukon
Mountain Height (metres) Height (feet) Rank
Mount Logan 5,959 19,550 Highest mountain in Canada
Mount Saint Elias 5,489 18,008 #2 in both Canada and the USA
Mount Lucania 5,226 17,147 #3 in Canada
King Peak 5,173 16,971 #4 in Canada
Mount Steele 5,073 16,644 #5 in Canada
Mount Wood 4,842 15,885 #7 in Canada
Mount Vancouver 4,812 15,787 #8 in Canada
Mount Slaggard 4,742 15,557 #10 in Canada
Mount Macaulay 4,690 15,387
Mount Hubbard 4,577 15,015
Mount Walsh 4,507 14,787
Mount Alverstone 4,439 14,565
McArthur Peak 4,389 14,400
Mount Augusta 4,289 14,070

[edit] Hydrography

See also: List of Yukon lakes and List of Yukon rivers

Most of the territory is in the watershed of its namesake, the Yukon River, which flows into the Bering Sea. The southern Yukon is dotted with a large number of large, long and narrow glacier-fed alpine lakes, most of which flow into the Yukon River system. The larger lakes include: Teslin Lake, Atlin Lake, Tagish Lake, Marsh Lake, Lake Laberge, Kusawa Lake, Kluane Lake. Lake Bennett on the Klondike Gold Rush trail is a smaller lake flowing into Tagish Lake.

Other rivers flow either directly into the Pacific Ocean or directly or indirectly into the Arctic Ocean. The Alsek-Tatshenshini drainage flows directly into the Pacific from the southwestern Yukon. A number of rivers in the northern Yukon flow directly into the Arctic Ocean. The two main Yukon rivers flowing into the Mackenzie River in the Northwest Territories are the Liard River in the southeast and the Peel River and its tributaries in the northeast.

[edit] Climate

Most of the Yukon has a subarctic climate (Köppen climate classification Dfc), characterized by long cold winters and brief warm summers. The airstrip at Snag, 25 kilometres east of Beaver Creek near the Alaska border, experienced the lowest ever temperature measured in North America, -63.0 °C (-81.4 °F) on February 3, 1947. The Arctic Ocean coast has a Tundra climate (ET). The climate is generally very dry, with little precipitation, but is considerably wetter in the southeast. Precipitation is much greater in the mountains, and the snowpack continues to melt well into the summer, resulting in high water in July or August.

Representative Climate Normals
Zone Average annual temperature Average July daily high Average January daily low Average snowfall Average rainfall
North (Old Crow) -9.0 °C 21 °C -36 °C 129 cm 144 mm
Central (Dawson City) -4.4 °C 23 °C -31 °C 160 cm 200 mm
South (Whitehorse) -0.7 °C 21 °C -22 °C 145 cm 163 mm
Southeast (Watson Lake) -2.9 °C 21 °C -29 °C 197 cm 255 mm

Source: Environment Canada, Canadian Climate Normals or Averages 1971-2000

[edit] Ecology

Except for the Arctic Ocean coastal plain and high elevations, most of the Yukon is in the boreal forest ecoregion. Most mountain peaks and higher elevations are characterized by Alpine tundra while the Arctic coastal plain is Arctic tundra. More precisely, according to Environment Canada's ecozone definitions, the southern and central Yukon is part of the Boreal Cordillera Ecozone while the northern forest is part of the Taiga Cordillera Ecozone. The Peel River area in the northeast is in the Taiga Plains Ecozone and the Arctic coast is in the Southern Arctic Ecozone.

Fireweed Epilobium angustifolium, the Yukon's territorial flower and White Spruce (Picea glauca) in the southern Yukon near the South Klondike Highway.
Fireweed Epilobium angustifolium, the Yukon's territorial flower and White Spruce (Picea glauca) in the southern Yukon near the South Klondike Highway.

[edit] Flora

Black Spruce (Picea mariana), White Spruce (Picea glauca), Quaking Aspen (Populus tremuloides) and Balsam poplar (Populus balsamifera) are found throughout the territory. Although relatively uncommon, the Alaska birch (Betula neoalaskana) is also found in most areas. The Lodgepole Pine (Pinus contorta) reaches its northern extreme the south-central part of the territory, while Tamarack (Larix laricina) is found in the southeast and the Sub-Alpine fir (Abies lasiocarpa) is found at higher elevations in the southern part of the Territory.

[edit] Fauna

The large mammals found throughout the territory include Caribou (Rangifer tarandus, both barren-ground and woodland), Moose (Alces alces), Wolves (Canis lupus), Grizzly bears (Ursus arctos horribilis) and American black bears (Ursus americanus). Higher elevation have Dall sheep (Ovis dalli) and, in the south, Rocky Mountain Goat (Oreamnos americanus). Polar Bears (Ursus maritimus) are found on the Arctic coast. The Mule deer (Odocoileus hermionus) and its predator, the Cougar (Puma concolor), are becoming increasingly common in the south, and Coyotes (Canis latrans) are increasing their range to the northern Yukon. Elk and Bison have been introduced.

There are many species of rodents, including Squirrels, Ground squirrels, Lemmings, Pikas, Beavers, various Voles, Porcupines, Muskrats, etc. Mustelids are also well represented and include the Wolverine (Gulo gulo), Marten (Martes Americana), Ermine (Mustela erminea), Least Weasel (Mustela nivalis), American Mink (Mustela vison), and the River Otter (Lontra Canadensis). Other small carnivores present are the Lynx (Lynx canadensis), Red Fox ( Vulpes vulpes) and Arctic Fox (Alopex lagopus) along the northern coast.

More than 250 species of birds have been sighted in the Yukon. The Common Raven (Corvus corax) is the territorial bird and is common everywhere. Other common resident birds include Bald Eagles (Haliaeetus leucocephalus), Golden Eagles (Aquila chrysaetos), Gyrfalcon (Falco rusticolus) and Peregrine falcon (Falco peregrinus), five species of grouse (Spruce Grouse, Blue Grouse, Ruffed Grouse, Ptarmigan, and White-tailed Ptarmigan). Many migratory birds breed in the Yukon, as it is at the northern end of the Pacific Flyway.

Other than the Burbot and Northern Pike, most of the large fish found in Yukon rivers, lakes and streams are Salmonids. Four species of Pacific salmon (Chinook, Sockeye, Coho and Chum) breed in Yukon rivers and lakes in the Pacific and Yukon River watersheds. The Yukon River has the longest freshwater migration route of any salmon; Chinook salmon swim over 3,000 kilometres from its mouth in the Bering Sea to spawning grounds upstream of Whitehorse. There are also land-locked kokanee (Sockeye Salmon) and Rainbow trout. Chars are represented by Lake trout present in most large Yukon lakes, as well as Dolly Varden, Bull trout and Arctic char. The Arctic Grayling is ubiquitous, while the lakes have various Whitefish and Inconnu.

There are no reptiles in the Yukon, but a few frogs.

Environment Canada, Pacific and Yukon Region Ecozones and Ecoregions

[edit] Human Geography

The Yukon is sparsely populated, with about 30,000 inhabitants in a territory almost as large as Spain or Sweden. Population density is 0.06 people per km². Close to three quarters of the population is in the Whitehorse area, and the rest live in a number of other communities. All except Old Crow are accessible by road.

The capital, Whitehorse, is also the largest city with more than two thirds of the population; the second largest is Dawson City, (pop. 1800) which was the capital until 1952.

Traditionally, the Yukon was inhabited by nomadic Athapaskan-speaking First Nations people who had established extensive trading networks with the Pacific Coast Tlingit. The interior people traded copper, furs and meat for coastal products such as eulachon oil. About 20% of the Yukon population is of aboriginal origin.

There is no Inuit population in the Yukon, although there was a population along the Arctic Ocean coast within historic times. The Inuit were decimated by disease and disappeared in the 19th century.

The following table presents the population of most Yukon communities. Note that the Census data represents those people who lived within the community boundaries, while the Yukon Bureau of Statistics (YBS) includes everyone with a postal address in the community. Typically, many people live immediately outside the community boundaries, hence the larger YBS numbers.

Population of Yukon Communities
Community 2001
Census		 1996
Census		 June 2005
YBS
Whitehorse (Agglomeration) 23,272 23,272 23,608
Whitehorse (City) 19,157 19,058 23,272
Dawson City 1,251 1,287 1,826
Watson Lake2 1,138 1,148 1,522
    Town of Watson Lake only 912 993 n/a
Haines Junction 531 574 817
Carmacks 431 466 378
Marsh Lake¹ 400 n/a 336
Mt. Lorne¹ 379 399 n/a
Mayo 366 324 378
Ross River 337 352 345
Pelly Crossing 328 238 281
Ibex Valley¹ 315 322 n/a
Faro 313 1,261 381
Old Crow 299 278 259
Teslin3 267 309 417
Tagish 206 164 187
Carcross4 201 292 444
Beaver Creek 88 131 120
Burwash Landing 68 58 89
Destruction Bay 43 34 59
Yukon Total 28,674 30,766 31,222

Notes:
 1 Part of Whitehorse Census Agglomeration
 2 Includes the town and adjoining First Nations settlements of Upper Liard and Two and One-Half Mile Village.
 3 Includes both the Village of Teslin and the adjoining Reserve
 4 Includes both the settlement and the adjoining Reserve

[edit] Natural Resources

The Yukon has abundant mineral resources and mining was the mainstay of the economy until recently. Abundant gold was found in the Klondike region leading to the Klondike Gold Rush of 1898. Placer gold is found in many streams and rivers, and there is an active placer mining industry in the Klondike and many other parts of the Yukon to this day.

Other minerals that have been actively mined include copper in the Whitehorse area, lead and zinc in Faro, silver, zinc and lead in the Mayo/Keno City area, asbestos in Clinton Creek, and copper, gold, and coal in the Carmacks area. The world's largest known deposit of tungsten is in the Macmillan Pass area in the Mackenzie Mountains near the Northwest Territories border. Non-metallic minerals mined have included jade and barite.

The fur trade was very important to the Yukon First Nation economy, but low prices and the impact of animal rights activists have devastated the traditional economy.

There are three hydroelectric generating stations in the Yukon: one at Schwatka Lake in Whitehorse, another near Mayo and a third on Aishihik Lake.

While the Yukon is mostly covered with forests, most of the trees are small and take a long time to grow and regenerate because of the dry cold climate. There is a considerable amount of small scale logging, but the only area that can sustain industrial forestry is in the southeast with its wetter climate. However, distance from markets and fluctuating prices have resulted in a boom-and-bust industry.

A small amount of natural gas is currently produced in the southeast, but little exploration has been done in other parts of the Yukon. It is believed that there are abundant natural gas fields in the Eagle Plains area along the Dempster Highway and possibly in the Whitehorse area, but distance from pipelines has hampered exploration.

[edit] Environmental issues

Global warming is affecting the north more than other parts of the world and the Yukon is no exception. While residents might welcome warmer temperatures, the ultimate effects are not known. Higher temperatures would mean more evaporation and drying out an already dry climate, resulting in more forest fires and reducing the biological productivity of boreal forests, whose growth is limited more by lack of moisture than temperature.

The Yukon is also the recipient of airborne pollutants from other parts of the world, especially Persistent Organic Pollutants. Consumption of the liver of certain wild animals and fish is no longer recommended because of these.

Locally, mine reclamation and dealing with mine tailings that cause acid mine drainage left over from mine closures is a major problem and is likely to cost hundreds of millions of dollars to clean-up.

In an effort to encourage natural resource exploration, the current (2005) Yukon Party government led by Dennis Fentie has suspended the application of the Protected Areas Strategy (established by a previous Yukon New Democratic Party government) and has indicated its intention of not creating additional protected areas or parks.

The Gwichʼin people of Old Crow are dependent on the Porcupine caribou herd for food and clothing, as are others in the Yukon. The Porcupine caribou herd migrates to the coastal plain in the Arctic National Wildlife Refuge (ANWR) in Alaska to give birth. That herd may be seriously threatened by oil-drilling in the ANWR.

[edit] References

[edit] External links

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