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The Subarctic is a region in the Northern Hemisphere immediately south of the true Arctic and covering much of Canada and Siberia, the north of Scandinavia, northern Mongolia and the Chinese province of Heilongjiang. Generally, subarctic regions fall between 50°N and 70°N latitude, depending on local climates.

In the Köppen climate classification system it is defined as the region where mean monthly temperatures are above 10 °C for at least one and at most three months of the year. This corresponds to Köppen climate types Cfc, Dfc, Dfd, Dwc and Dwd. In most subarctic climates, aside from the maritime Cfc, precipitation tends to be low due to the low moisture content of the cold air. Typically there is a summer maximum in precipitation ranging from moderate in North America to extreme in the Russian Far East. Except in the wettest areas, glaciers are largely absent because of the lack of winter precipitation; in the wettest areas, however, glaciers tend to be very abundant and Pleistocene glaciation covered even the lowest elevations. Soils of the subarctic are generally very acidic largely because of the influence of the vegetation both in the taiga and in peaty bogs, which tends to acidify the soil, as well as the extreme ease with which leaching of nutrients takes place even in the most heavily glaciated regions. The dominant orders are Spodosols and further north Gelisols.

Subarctic regions are often characterized by taiga forest vegetation, though where winters are relatively mild, as in northern Norway, broadleaf forest may occur - though in some cases soils remain too saturated almost throughout the year to sustain any tree growth and the dominant vegetation is a peaty herbland dominated by grasses and sedges. Typically, there are only a few species of large terrestrial mammals in the subarctic regions, the most important being moose (Alces alces), bears, reindeer Rangifer tarandus, and the wolf (Canis lupus). Agriculture is mainly limited to animal husbandry, though in some areas barley can be grown. Canada and Siberia are very rich in minerals, notably nickel, molybdenum. cobalt, lead, zinc and (since the 1940s) uranium, whilst the Grand Banks and Sea of Okhotsk are two of the richest fisheries in the world and provide support for many small towns.

Except for those areas adjacent to warm ocean currents, there is almost always continuous permafrost due to the very cold winters. This means that building in most subarctic regions is very difficult and expensive: cities are very few (Murmansk being the largest) and generally small, whilst roads are few and railways non-existent. An important consequence is that transportation tends to be restricted to "bush" planes, helicopters and, in summer, river boats.

Except for a few parts of Europe where the winters are relatively mild due to prevailing wind patterns, subarctic regions were not explored until the eighteenth and nineteenth centuries. Even then, the difficulty of transportation ensured that few settlements (most of them created for mining) lasted long - the ghost towns of the Yukon, Northwest Territories and increasingly Siberia illustrate this.

The Trans-Siberian Railway, which skirts the edge of the region, provided a major boost to Russian settlement in the subarctic, as did the intensive industrialisation under Stalin that relied on the enormous mineral resources of the Central Siberian Plateau. Today, many towns in subarctic Russia are declining precipitously as former mines close. In Canada, after the early minerals run out, development stalled until hydroelectric development occurred in the 1950s and 1960s. Hydro-Québec in particular has carried out many remarkable engineering works in regions of near-continuous permafrost, but these have never supported a significant population and have mainly served densely populated southern Québec.

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

• Subarctic climate