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Subarctic

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Region in the Northern Hemisphere immediately south of the true Arctic
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See caption
Global map of the subarctic region

Thesubarctic zone is a region in theNorthern Hemisphere immediately south of the trueArctic, north ofhemiboreal regions and covering much ofAlaska,Canada,Iceland, the north ofFennoscandia,Northwestern Russia,Siberia, and theCairngorms. Generally, subarctic regions fall between 50°N and 70°Nlatitude, depending on local climates. Precipitation is usually low, and vegetation is characteristic of thetaiga.

Daylight at these latitudes is quite extreme between summer and winter due to its high latitude. Near the summersolstice for instance, subarctic regions can experience an all-night period of either civil, nautical, or astronomical twilight (or in the northern reaches full daylight), since the sun never dips more than 18 degrees below the horizon.Noctilucent clouds are best observed within this range of latitude.

Climate and soils

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Subarctic vegetation in Canada (Larix laricina)

Subarctic temperatures are above 10 °C (50 °F) for at least one and at most three months of the year. Precipitation tends to be low due to the low moisture content of the cold air but isn't to the point tosemiarid regions. Precipitation is typically greater in warmer months, with a summer maximum ranging from moderate inNorth America to extreme in theRussian Far East. Except in the wettest areas glaciers are not large because of the lack of winter precipitation; in the wettest areas, however, glaciers tend to be very abundant andPleistoceneglaciation covered even the lowest elevations.Soils of the subarctic are in which leaching of nutrients takes place even in the most heavily glaciated regions. The dominant soil orders arepodsols[1] and, further north,gelisols.

Subarctic regions are often characterized bytaiga forest vegetation asdeciduous trees can't withstand the long winters, though where winters are relatively mild, as innorthern Norway,broadleaf forest may occur—though in some cases soils remain too saturated almost throughout the year to sustainanytree growth and the dominant vegetation is a peaty herbland dominated bygrasses andsedges. Typically, there are only a few species of large terrestrialmammals in the subarctic regions, the most important being elk,moose (Alces alces),bears,reindeer (Rangifer tarandus), andwolves (Canis lupus).Agriculture is mainly limited toanimal husbandry as many crops can't be grown here, though in some areasbarley can be grown.Canada andSiberia are very rich in minerals, notablynickel,molybdenum,cobalt,lead,zinc anduranium, whilst theGrand Banks andSea of Okhotsk are two of the richestfisheries in the world and provide support for many small towns.

Except for those areas that are well-drained or adjacent to warmocean currents, there is almost always continuouspermafrost due to the very cold winters and short summers.[2] This means that building in most subarctic regions is very difficult and expensive: cities are very few (Murmansk being the largest) and generally small, whilstroads are also few. Subarctic rail transport only exists inEurope (lines toNarvik and Murmansk) and theNorilskDudinka line in northernSiberia, as well as theAlaska Railroad in Alaska and short sections of rail lines in Canada reaching northward into the lower subarctic. An important consequence is that transportation usually tends to be restricted to"bush" planes,helicopters and, in summer,riverboats. In areas that receive lower rainfall they tend to be covered bygrasslands.

Economy

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InFennoscandia and northwesternRussia, oceanic influences soften winter temperatures; the lack of permafrost allow agriculture and infrastructure.Senja Municipality, Norway, at 69°N.
Images taken nearUnalakleet show very few trees, reflecting the subarctic and polar boundaries.

Except for a few parts ofEurope where the winters are relatively mild due to prevailing wind and ocean current patterns, subarctic regions were not explored until the 18th and 19th centuries. Even then, the difficulty of transportation ensured that few settlements (most of them are created formining) lasted long—such as the abandoned, once-thriving cities of theYukon,Northwest Territories[3] and increasingly Siberia illustrate this.

TheTrans-Siberian Railway, which skirts the edge of the region, provided a major boost to Russian settlement in the subarctic, as did the intensive industrialization underJoseph Stalin that relied on the enormous mineral resources of theCentral Siberian Plateau. Today, many towns in subarctic Russia are declining precipitously as mines close. In Canada, after the early minerals ran out, development stalled untilhydroelectric development occurred in the 1950s and 1960s.Hydro-Quebec in particular has carried out many engineering works in regions of near-continuous permafrost, but these have never supported a significant population and have only mainly served densely populated southernQuebec.

Tourism in recent years has become a major source of revenue for most countries of the subarctic due to the beautiful, generally glacial landscapes so characteristic of the region. Most areas in the subarctic are among the most expensive places in the world to visit, due to both high costs of living and transportation inaccessibility. Nonetheless, the great opportunities foroutdoor recreation lure an ever-increasing number of travelers. At the same time, the older industries of the subarctic (fishing, mining, hydroelectric power) are being threatened by bothenvironmental opposition andoverfishing leading to depleted stocks of commercially important species living in this region.

See also

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References

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  1. ^"Podzol | Encyclopedia.com".www.encyclopedia.com. Retrieved24 March 2022.
  2. ^Pettapiece, W. W. (1975)."Soils of the Subarctic in the Lower Mackenzie Basin".Arctic.28 (1):35–53.doi:10.14430/arctic2812.ISSN 0004-0843.JSTOR 40509243.
  3. ^"Fort Yukon | historical settlement, North America | Britannica".www.britannica.com. Retrieved24 March 2022.

External links

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  • "Subarctic climate" in: Ritter, Michael E.The Physical Environment: an Introduction to Physical Geography. 2006.
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