Cold temperate climate

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  • Cold temperate ( boreal ) climatic zone of the earth
  • The cold-temperate climate , also known as the boreal coniferous forest climate , snow forest climate or sub-arctic climate (however, this is also the name of the sub- polar climate in the northern hemisphere), is the coldest of the climate types in the temperate zone and largely corresponds to the boreal vegetation zone . This type of climate occurs mainly in the northern hemisphere and there especially in northern Asia and North America . The only larger cold temperate land area in the southern hemisphere is in the south of South America in the Patagonia region . The area with a cold temperate climate is called the cold temperate climate zone .

    definition

    • Average temperature in the warmest month over 10 ° C
    • Average temperature in the coldest month below −3 ° C (according to some definitions below 0 ° C)
    • humid climate without pronounced dry seasons, but with a summer maximum of precipitation
    • Vegetation period approx. 4 months (T> 5 ° C)
    • δT at 39 ° C; δN à95 mm
    • short summer
    • Continental climate

    classification

    description

    The cold, temperate, boreal climate tends to have little precipitation away from the coastal areas, and within continental regions with a summer maximum of precipitation. Because of the low temperatures in winter with little rainfall, the climate can still be described as humid . It is also characterized by extreme temperature fluctuations (up to 100 ° C / a; continental climate). In winter very low temperatures can be observed (down to –40 ° C in January mean), the short summers, on the other hand, are extremely warm and with their temperatures are similar to the conditions of the cool, moderate middle latitudes. However, the daily temperature fluctuations are very small.

    The climate of the cold temperate, boreal zone is continentally influenced. Due to the huge land masses of Asia and North America, this zone is under the influence of a continental cold peak. It is bounded to the north by the subpolar depression . The extreme temperature fluctuations can also be explained by the continental influence of the cold-temperate, boreal climate.

    Geographical classification

    The cold temperate boreal climate stretches in a belt around the entire earth. This is between 1000 and 3500 km wide. On the warm western sides (warm ocean currents, e.g. Gulf Stream) of the continents it extends less far to the south than on the cooler eastern sides. In the south, the boreal zone is bounded by the maritime humid climates of the coastal areas in East Asia , East America and Western Europe. While the boreal climate in the continental part can penetrate beyond the borders of the USA, it is "displaced" further and further north towards the Pacific coast as far as Alaska. On the European mainland it extends almost to the Black Sea and is limited to the east by the 20th degree of longitude, with the exception of Scandinavia, where the boreal climate can penetrate to the west coast. On the Asian continent, the southern limit of the climatic zone runs roughly along the 50th parallel , with the east coast expanding slightly towards the south. To the north, the boreal zone is bounded by the ice climates , in Asia and Europe it extends almost to the Arctic Ocean , in North America the Hudson Bay and the Canadian archipelago are exempt from the cold-temperate, boreal climate, but towards the west coast it shifts again to the north the Beaufort Sea .

    Germany

    Germany lies mostly in the cool temperate zone . There are also areas that have a cold temperate climate due to their altitude. These areas are the Upper Harz , the northern Bavarian Forest as well as the edge of the Alps and the highest areas of the Rothaargebirge .

    Floors

    The predominant soil types in the cold-temperate, boreal zone are Gleye in the north and Podzole (main soil type) in the south . They occur like a band (zonal according to the zonal vegetation ) in an east-west direction.

    Gleye

    From soil water significantly influenced soil ( Vergleyung ), has what a high groundwater level, which until Ah - horizon may be enough. Humous, lime-poor A-horizon , which is approx. 20-30 cm thick. Because of chemical weathering , the subsoil is very rich in clay ( G horizon ). Because of the lack of oxygen caused by the high water level, the iron and manganese compounds are reduced and excreted again at the fluctuating groundwater level . This leads to a mottled Go horizon . The Gr horizon (reduction horizon ) below is crossed by green-blue-gray streaks. Basically, gley soils are difficult to work with, as the plant nutrients are very mobile due to the high water level . They can hardly be used for arable farming.

    Podsole

    Favorable conditions for the formation of Podsolen ( Podsolierung ) are high precipitation, raw humus- forming vegetation and permeable, acidic rock. Because of the scarcely existing soil life, a mighty raw humus layer forms, which forms the Ah horizon . When the humus layer decomposes, humic acids are formed , which promote the weathering of silicate . Almost all existing clay minerals , aluminum, iron and magnesium compounds as well as the nutrients are washed out by the seepage water and washed through to the subsoil. This is why this part of the soil is also called the bleaching horizon ( Ae horizon ). The substances washed out above are stored in the Bs horizon and form a cast stone from the iron, silicon and magnesium compounds , an almost water-impermeable layer of rock, which is practically not penetrable for roots and thus makes the soil unattractive for agricultural use. Only intensive care and possible breaking of the stone, provided that it is not too deep, make this soil halfway productive.

    vegetation

    The potential natural vegetation is a boreal coniferous forest , which merges to the north into a tundra with subpolar woody plants. In the few mountain zones of the cold-temperate, boreal climate, a mountain coniferous forest potentially grows (e.g. Ural , northern Rocky Mountains ). The boreal coniferous forest consists mainly of tall, narrow-crowned and dense firs and spruces . Mosses and berry bushes can be found on the ground . In order to come to terms with the inhospitable climate, the trees grow only very slowly, around 15-20 times slower than the tropical rainforest. The forest is also much more vulnerable than other forests to external interference such as clearing, forest fires or temperature fluctuations.

    Since agriculture is hardly possible in the boreal area due to the poor soil quality and the low temperatures, people in these areas have relied on other sources of income. So the entire boreal space is rich in natural resources. For example, Siberia has the largest natural gas reserves in the world (100 trillion m³), ​​which is one of Russia's most important export goods. Iron ore and coal can also be found here. It looks even better in Canada: Here you have the world's largest uranium and potash deposits. But Canada is also among the best in the world when it comes to nickel, zinc, copper, gold and diamond mining. Problems arise with the exploitation of these mineral resources due to the high use of heavy metals such as arsenic, lead and mercury, which put massive strain on the surrounding soil. Another branch of the economy is the wood industry , which of course is one of the most important industries in the huge forests. This is problematic because, due to the adverse conditions, the boreal coniferous forest is much more sensitive to clearing than other forests and can only regenerate poorly. Fur animals are also hunted and bred in the boreal forests, as the low temperatures make the skins particularly dense and bushy and very popular. This economy is becoming less important as the fur industry's bad reputation makes it difficult to sell fur.

    Individual evidence

    1. Geoclimate 2.1