Concept
The subarctic zone is a region in the Northern Hemisphere immediately south of the true Arctic, north of humid continental regions and covering much of Alaska, Canada, Iceland, the north of Scandinavia, Siberia, and the Cairngorms. Generally, subarctic regions fall between 50°N and 70°N latitude, depending on local climates. Precipitation is usually low, and vegetation is characteristic of the taiga. Daylight at these latitudes is quite extreme between summer and winter due to its high latitude. Near the summer solstice for instance, subarctic regions can experience an all-night period of either civil, nautical, or astronomical twilight (or in the northern reaches full daylight), but without true night, since the sun never dips more than 18 degrees below the horizon. Noctilucent clouds are best observed within this range of latitude. Subarctic temperatures are above 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 to semiarid regions. Precipitation is typically greater in warmer months, with a summer maximum ranging from moderate in North America to extreme in the Russian 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 and Pleistocene glaciation 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 are podsols and, further north, gelisols. Subarctic regions are often characterized by taiga forest vegetation as deciduous trees can't withstand the long winters, 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.