1.Introduction
Alaska, one of the Pacific coast states, and the northern state of the United States, occupying the north-western extremity of North America. It is bordered on the north by the Arctic Ocean; on the east by Canada (the Yukon Territory and British Columbia); on the south-east, south, and south-west by the Pacific Ocean; and on the west by the Bering Sea, Bering Strait, and Arctic Ocean. The state includes two major island groups: the Aleutian Islands, which extend in an arc west from the south-western corner of the mainland, and the Alexander Archipelago, adjacent to the south-eastern coast of the mainland.
Sometimes known as the “Last Frontier”, Alaska entered the Union on January 3, 1959, as the 49th state. The wild grandeur of the state has fascinated people for several hundred years. Its economy, traditionally dominated by the exploitation of natural resources, entered a new phase in 1977, when oil production began at the vast Prudhoe Bay oilfield on the Arctic coast. The name of the state is derived from an Aleut word meaning “mainland”. Its major cities are Juneau* , Anchorage**, Fairbanks, Sitka, and Ketchikan.
*Juneau,a port town and the capital of Alaska, is the commercial and distribution centre for the panhandle region of the state. Industries include fishing and fish processing, logging, mining, and tourism. Transport to and from the town is principally by boat or aeroplane.
Juneau is the site of the Alaska State Museum, the Last Chance Mining Museum, and the University of Alaska Juneau. Mendenhall Glacier and Glacier Bay National Park are located nearby.
In 1880 Joseph Juneau and Richard Harris discovered gold in the area, which led to the development of the settlement as a gold-mining town. In 1970 Juneau’s boundaries were greatly extended, making it one of the largest communities in area in the United States.
**A seaport on the Knik Arm of Cook Inlet in southern Alaska, the city of Anchorage serves as the transport and commercial centre for much of the central and western parts of the state. Established in 1914 as the main supply base for the Alaska Railroad to Fairbanks, Anchorage grew significantly during World War II with the construction of two United States military bases—Fort Richardson and Elmendorf Air Force Base. Now Anchorage is the largest city in the state and a major international centre for air freight. The city’s economy depends on the exploitation of Alaska’s natural resources: petroleum, natural gas, and fish.
Anchorage underwent major expansion during the 1980s when the Museum of Art and History, a sports arena, a convention centre, and the Alaska Center for the Performing Arts were constructed.
2. Land and Resources
With a total area of 1,593,438 sq km , Alaska is the largest state in the United States, with an area equal to about one fifth of that of the contiguous 48 states. About 81 percent of the land is owned by the federal government. The state is roughly square in shape with two major projections: the Alaska Peninsula, with its geographical extension, the Aleutian Islands; and the Panhandle, which extends from the south-eastern body of the state along the border of British Columbia, Canada. Its extreme dimensions are about 2,240 km from north to south and about 3,550 km from east to west. Alaska has the greatest relief range of any state; elevations begin at sea level and extend up to 6,194 m
in Mount McKinley , the highest peak in North America. The approximate mean elevation is 580 m . Alaska has about 8,980 km of shoreline on the Pacific Ocean and 1,706 km of shoreline on the Arctic Ocean.
3. Physical Geography
Alaska is divided into three main regions: the Pacific Mountains along the entire southern coastal area; the Interior, a central belt of plateaux and plains; and the Alaska North Slope, or Arctic Slope.
The Pacific Mountain system is a group of ranges set in a geologically unstable belt surrounding the Pacific Ocean. Volcanic and earthquake activity is much in evidence here. The south-eastern part of the Pacific mountain system, or Panhandle, is a region of fiords and glaciers comprising the rugged Boundary Range and the offshore Alexander Archipelago, which in turn contains the sheltered Inside Passage - one of the most scenic natural waterways in the world.
At the north-western corner of the Panhandle is the St Elias Range, with some of the highest peaks on the continent, largely covered with ice and snow and containing the spectacular Malaspina Glacier, the largest in the state. Just north of the St Elias Mountains are the volcanic Wrangell Mountains, which include Mount Wrangell, Mount Sanford, and Mount Drum. Other ranges in the Pacific Mountains include the arc-shaped Alaska Range, which includes Mount McKinley, and the Chugach and Kenai mountains.
The Interior comprises the Brooks Range*** a complexly folded sedimentary mass extending across the entire width of Alaska the Tanana Hills and Kuskokwim Mountains, and the wide flat valley and delta of the Yukon River.
The Alaska North Slope, also known as the Arctic Lowland or Arctic Plain, slopes gradually downwards from the base of the Brooks Range to the Arctic Ocean. In the south, where elevations exceed 610 m , drainage is good. In the north, however, are many hundreds of undrained ponds.
Alaska's major river, the Yukon, is one of the longest on the North American continent; it flows across the state from east to west, emptying into the Bering Sea. About two thirds of its 3,185 km course lies within Alaska. The Yukon's tributaries include the Porcupine, Koyukuk, and Tanana rivers. The state has thousands of small lakes, of which the largest (Iliamna, Becharof, and Ugashik) are located on the Alaska Peninsula.
***The Coast Ranges include geologically dissimilar sections that are nevertheless grouped together as a system because of their geographic location along the Pacific Coast from southern Alaska to Baja California. The loftiest elevations of the Coast Ranges are in the north, especially in the St Elias Mountains, which include Mount Logan (6,050 metres/19,850 feet), the second highest peak in North America, and Mount St Elias (5,489 metres/18,008 feet). The Coast Ranges have a wide variety of climate and vegetation. Sections in southern California and Mexico receive little precipitation and have few stands of large trees. Well-watered regions in northern California, Oregon, and Washington and on Vancouver Island, however, contain dense softwood forests,where logging is an important economic activity.
4. Climate
Alaska can be divided into three major climate zones: a region of maritime influences (a marine west coast climate), a region of continental (or subarctic) climate, and a region of tundra (or arctic) climate.
The region of maritime climate comprises the Panhandle, the coast of the Gulf of Alaska, and the Aleutian Islands. Grey skies, successive wet days, dampness, fogginess, and occasional gales are characteristic here, and the abundant snowfall provides the source for many glaciers. Summers are cool, and winters relatively mild.
The region of continental climate comprises Interior Alaska, the area north of the Alaska Range and south of the Brooks Range, where there are mild, brief summers and harsh winters. The average January temperature is -22.8° C , with extremes of -51.1° C or colder. A record low temperature of -62.2° C was measured at Prospect Creek Camp, in north-western Alaska, in 1971.
The area north of the Brooks Range has an arctic climate, with weeks of continuous darkness in winter and of daylight in summer.
5. Plants and Animals
Vegetation ranges from lush coniferous forests, located in the Panhandle and on the coast of the Gulf of Alaska, dominated by hemlock, spruce and birch trees, to a treeless tundra. Much of the interior is covered by taiga, or northern forest, consisting largely of spruce and birch. Alaska's many flowers include fireweed, lupine, and the state flower, forget-me-not.
Alaska has a rich and diverse fauna. Surrounding waters are renowned for whale, fur seal, walrus, and sea otter, as well as salmon, halibut, crab, shrimp, and other marine life. Bears, including polar, brown, and black, are well represented. Great herds of caribou still migrate across the Brooks Range, followed by packs of wolves.
Other mammals include moose, as well as beaver, wolverine, mink, otter, and muskrat. Several species of ptarmigan are widespread, and large numbers of ducks and geese spend summers on the Arctic slope. Mosquitoes swarm in vast numbers in summer; also present are flies and “no-see-ums”, as the biting midges are known.
6. Resources, Products, and Industries
Oil from the vast Prudhoe Bay oil field (via the Trans-Alaska Pipeline, opened in 1977) and natural gas are by far Alaska's most important mineral resources. Oil revenues have enabled the state to abolish its personal income tax and to distribute annual cash dividends to all state residents. However, oil production is now declining steadily, falling from a peak of 2 million barrels a day to 1.4 million in the mid-1990s as the Prudhoe Bay fields near depletion. In the early 1990s Alaska produced about 12.2 billion cu m of natural gas each year. Other minerals include copper, gold, coal, sand, molybdenum, gravel, stone, and clay. Forestry is important to the economy, the principal trees being western hemlock, Sitka spruce, cedar, and other softwoods, which are used for timber and paper-making. Fishing is also a thriving industry, with salmon accounting for a major share of the value of the annual catch. In the early 1990s the total catch in the state was 2.6 million tonnes, valued at US$1.6 billion. Farming accounts for less than 1 percent of the annual gross state product. Greenhouse products, dairy products, potatoes and cattle dominate agricultural output. Leading manufacturing industries are food processing and fish-processing, timber and wood products, and printing and publishing.
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