Climatic map of the Russian Plain. East European Plain: climate, natural areas, geographical location. Northern climatic region
The East European Plain is located in the eastern part of Europe, and there are 10 countries on its territory, but most of it is located in the west of Russia, which is why its second name is the Russian Plain. The climate of the Russian Plain depends on several factors: geographical position, relief, proximity to the ocean. So in what climatic zones is the Russian Plain located?
general information
The East European Plain is one of the largest plains on the planet. Its area occupies more than 4 million square meters. km. The Russian Plain is bounded in the north by the Arctic Ocean, in the south by the Caspian and Black Seas, the Caucasus Mountains, in the east by the Urals, in the west by the state border of Russia. The whole plain can be divided into 3 parts: central, southern and northern. The central strip is distinguished by large uplands and lowlands. So, for example, the Bugulma-Belebeevskaya Upland, located just in the central part, is the highest point of the plain. Its height is 479 meters.
Rice. 1. Bugulma-Belebeevskaya upland.
Of all the plains of Russia, only the Russian Plain has access to two oceans at once - the Arctic and the Atlantic.
Climate of the East European Plain
Most of the plain lies in the temperate climate zone. It is formed under the influence of air masses brought from the Atlantic Ocean. This type of climate of the East European Plain is characterized by rather cold winters and warm summer. Depending on the area, the average temperature in summer varies from +12 degrees (for example, the coast of the Bering Sea) to +24 (for example, in the Caspian lowland). The average January temperature varies from -8 degrees in the western part to -16 degrees in the Cis-Urals.
Rice. 2. East European Plain on the map.
The Russian Plain is subject to the western transfer of air masses. Due to the smooth relief of the plain, the transfer of air masses occurs freely. Westward air mass transfer is the movement of air from west to east. The Atlantic air brings coolness and rainfall in summer, and warmth and rainfall in winter.
A frequent occurrence in the cold season is the arrival of cyclones. During this time, from 8 to 12 cyclones can come to the Russian Plain.
TOP 4 articleswho read along with this
Precipitation is unevenly distributed across the plain. The most humid are the Valdai and Smolensk-Moscow Uplands.
Rice. 3. Valdai Hills.
A characteristic feature of the East European Plain is a clear manifestation of latitudinal zonality (a successive change of zones from tundra to semi-deserts). the average annual precipitation here is 700 mm.
Snow cover is characteristic of the entire territory of the Russian Plain. The duration of snow in the north can be 220 days a year, and in the south - 60 days.
What have we learned?
The East European Plain is characterized by a temperate continental climate. That is, in most of the territory, winters are cold, and summers are warm. The plain is characterized by cyclones, and it is also subject to the influence of western transport.
Topic quiz
Report Evaluation
Average rating: 3.9. Total ratings received: 262.
The climate is one of the most important physical and geographical characteristics of the territory. Climate is a long-term weather pattern characteristic of a particular area on Earth. In this case, the multi-year regime is understood as the totality of all weather conditions in a given area over a period of several decades; typical annual change of these conditions and possible deviations from it in individual years; weather combinations characteristic of its various anomalies (droughts, rainy periods, cooling, etc.).
The climate of the East European Plain is influenced by its position in temperate and high latitudes, as well as by the connection of the territory ( Western Europe and North Asia) and water areas (Atlantic and Arctic Oceans) (Appendix 4).
The Russian Plain is located in temperate and high latitudes, where seasonal differences in the arrival of solar radiation are especially large. The distribution of radiation over the territory of the plain changes dramatically with the seasons. In winter, radiation is much less than in summer, and more than 60% of it is reflected by the snow cover. The radiation balance in winter, with the exception of the extreme southern regions, is negative. It falls in the direction from the southwest to the northeast and depends mainly on the amount of cloudiness. In summer, the radiation balance is positive everywhere. It reaches its greatest value in July in the south of Ukraine, in the Crimea and the Sea of Azov. The total solar radiation increases from north to south from 66 to 130 kcal/cm2 per year. In January, the total solar radiation at the latitude of Kaliningrad-Moscow-Perm is 50, and the Ciscaucasia and the southeast of the Caspian lowland is about 150 MJ/m 2 .
All year round over the East European Plain, the western transport of air masses dominates, and the Atlantic air of temperate latitudes brings coolness and precipitation in summer, and warmth and precipitation in winter. When moving to the east, it transforms: in summer it becomes warmer and drier in the surface layer, and colder in winter, but also loses moisture. During the cold season, from 8 to 12 cyclones come from different parts of the Atlantic to the East European Plain. When they move to the east or northeast, there is a sharp change in air masses, contributing to either warming or cooling. With the arrival of southwestern cyclones (Atlantic-Mediterranean), and there are up to six of them in a season, warm air of subtropical latitudes invades the south of the plain. Then in January the air temperature can rise to +5° - 7°C and, of course, thaws come.
The arrival of cyclones from the North Atlantic and the southwestern Arctic to the Russian Plain is associated with the intrusion of cold air. Anticyclones often recur in the southeast of the plain, due to the influence of the Asian High.
In the warm period of the year, from April, cyclonic activity proceeds along the lines of the Arctic and Polar fronts, shifting to the north. Cyclonic weather is most typical for the northwest of the plain, so cool sea air from temperate latitudes often comes to these areas from the Atlantic. It lowers the temperature, but at the same time it heats up from the underlying surface and is additionally saturated with moisture due to evaporation from the moistened surface.
Cyclones contribute to the transfer of cold air, sometimes arctic, from the north to more southern latitudes and cause cooling, and sometimes frost on the soil.
The distribution of precipitation over the territory of the Russian Plain is primarily dependent on circulation factors. Cyclonic activity is observed mainly in the west, in the area of the Barents Sea. On the mainland Atmosphere pressure It is distributed in such a way that Arctic and Atlantic air flows into the plain, with which large clouds and significant precipitation are associated. The western transfer of air masses prevailing here is intensified due to the frequent recurrence of cyclones of the Arctic and Polar fronts. Especially often cyclones move from west to east between 55-60°N. sh. (Baltic, Valdai, upper reaches of the Dnieper). This strip is the most humid part of the Russian Plain: the annual amount of precipitation here reaches 600-700 mm. in the west and 500-600 mm in the east.
Winter cyclonic precipitation forms a snow cover with a height of 60-70 cm, which lies up to 220 days a year, to the south-west, the duration of the snow cover is reduced to 3-4 months a year, and its average long-term height is reduced to 10-20 cm. As we move deeper into the mainland, cyclonic activity and the associated western transport in the south of the East European Plain weakens. Instead, the frequency of anticyclones increases. Under the conditions of stable anticyclones, the processes of transformation of air masses intensify, as a result of which humid western air is quickly transformed into continental air. Because of this, precipitation in the southern part of the plain falls 500-300 mm per year, and their amount rapidly decreases in the southeast direction to 200 mm. and sometimes less. The snow cover is thin and lies for a short time: 2-3 months in the southwest. Relief influences the increase in annual precipitation. For example, in the Donetsk ridge falls 450 mm. precipitation, and in the surrounding steppe - 400 mm. The difference in the annual amount of precipitation between the Volga Upland and the low-lying Trans-Volga region is about 100 mm. In the southern half of the plain, the maximum precipitation occurs in June, and in the middle lane - in July. The southern half is characterized by the lowest, and the northern half by the highest relative humidity. The moisture index in the north of the territory is more than 0.60, and in the south 0.10.
Precipitation practically falls from all air masses, but most of it is associated with the Atlantic air of temperate latitudes. Tropical air brings a lot of moisture to the southwest. Precipitation is mainly due to the circulation of air masses on the Arctic and Polar fronts, and only 10% of them are produced by intramass processes in the summer.
The degree of moistening of the territory is determined by the ratio of heat and moisture. It is expressed in different quantities:
- a) moisture coefficient. On the East European Plain, it reaches values from 0.55 (the Crimean plains) to 1.33 or more (in the Pechora lowland);
- b) dryness index - from 3 (in the deserts of the Caspian lowland) to 0.45 (in the tundra of the Pechora lowland);
- c) the average annual difference in precipitation and evaporation (mm).
In the northern part of the plain, moisture is excessive, since precipitation exceeds evaporation by 200 mm or more. In the zone of transitional moisture from the upper reaches of the Dniester, Don and the mouth of the Kama, the amount of precipitation is approximately equal to evaporation, and the further south from this zone, the more and more evaporation exceeds precipitation (from 100 to 700 mm), i.e. insufficient moisture sets in.
Differences in the climate of the East European Plain affect the nature of the vegetation and the presence of a fairly clearly expressed soil-vegetation zonality.
B.P. Alisov, taking into account the radiation balance and atmospheric circulation (transport of air masses, their transformation, cyclonic activity), distinguishes three climatic regions in the European part:
- 1) northern Atlantic-Arctic;
- 2) the middle Atlantic-continental region;
- 3) southern continental region.
THE EAST EUROPEAN PLAIN, The Russian Plain, one of the largest plains in the world, within which are the European part of Russia, Estonia, Latvia, Lithuania, Belarus, Moldova, as well as most of Ukraine, West Side Poland and the eastern part of Kazakhstan. The length from west to east is about 2400 km, from north to south - 2500 km. The area is over 4 million km 2. In the north it is washed by the White and Barents Seas; in the west it borders on the Central European Plain (approximately along the valley of the Vistula River); in the southwest - with the mountains of Central Europe (Sudet and others) and the Carpathians; in the south it goes to the Black, Azov and Caspian seas, to the Crimean mountains and the Caucasus; in the southeast and east, it is bounded by the western foothills of the Urals and Mugodzhary. Some researchers include V.-E. R. the southern part of the Scandinavian Peninsula, the Kola Peninsula and Karelia, others refer this territory to Fennoscandia, the nature of which differs sharply from the nature of the plain.
Relief and geological structure
V.-E. R. geostructurally corresponds in general to the Russian plate of the ancient East European platform, in the south - northern part of the young Scythian platform, in the northeast - southern part of the young Barents-Pechora platform .
Complex relief V.-E. R. characterized by small fluctuations in altitude (average height is about 170 m). The highest heights are noted on the Podolsk (up to 471 m, Mount Kamula) and Bugulma-Belebeevskaya (up to 479 m) uplands, the lowest (about 27 m below sea level - the most low point Russia) is located on the Caspian lowland, on the coast of the Caspian Sea.
On V.-E. R. two geomorphological regions are distinguished: the northern moraine with glacial landforms and the southern extra-morainic with erosion landforms. The northern moraine region is characterized by lowlands and plains (Baltic, Upper Volga, Meshcherskaya, etc.), as well as small uplands (Vepsovskaya, Zhemaitskaya, Khaanya, etc.). To the east is the Timan Ridge. The far north is occupied by vast coastal lowlands (Pechora and others). There are also a number of large uplands - the tundra, among them - the Lovozero tundra, etc.
In the northwest, in the area of the Valdai glaciation, accumulative glacial relief prevails: hilly and ridge-moraine, depression with flat lacustrine-glacial and outwash plains. There are many swamps and lakes (Chudsko-Pskovskoye, Ilmen, Upper Volga lakes, Beloe, etc.), the so-called lake area. To the south and east, in the area of distribution of the more ancient Moscow glaciation, smoothed undulating secondary moraine plains, reworked by erosion, are characteristic; there are basins of lowered lakes. Moraine-erosion uplands and ridges (Belarusian Ridge, Smolensk-Moscow Upland, and others) alternate with moraine, outwash, lacustrine-glacial, and alluvial lowlands and plains (Mologo-Sheksninskaya, Upper Volga, and others). In some places, karst landforms are developed (the White Sea-Kuloi plateau, etc.). Ravines and gullies are more common, as well as river valleys with asymmetric slopes. Along the southern border of the Moscow glaciation, woodlands (Polesskaya lowland, etc.) and opolye (Vladimirskoye, Yuryevskoye, etc.) are typical.
In the north, insular permafrost is widespread in the tundra, in the extreme northeast - continuous permafrost up to 500 m thick and with temperatures from -2 to -4 °C. To the south, in the forest-tundra, the thickness of permafrost decreases, its temperature rises to 0 °C. Permafrost degradation, thermal abrasion on sea coasts with destruction and retreat of coasts up to 3 m per year is noted.
For the southern extra-morainic region V.-E. R. characterized by large uplands with erosion ravine-gully relief (Volyn, Podolsk, Pridneprovsk, Azov, Central Russian, Volga, Ergeni, Bugulma-Belebeevskaya, General Syrt, etc.) and outwash, alluvial accumulative lowlands and plains belonging to the area of the Dnieper and Don glaciation (Pridneprovskaya, Oksko-Donskaya, etc.). Wide asymmetric terraced river valleys are characteristic. In the southwest (the Black Sea and Dnieper lowlands, the Volyn and Podolsk uplands, etc.) there are flat watersheds with shallow steppe depressions, the so-called "saucers", formed due to the widespread development of loess and loess-like loams. In the northeast (High Trans-Volga, General Syrt, etc.), where there are no loess-like deposits and bedrocks come to the surface, the watersheds are complicated by terraces, and the peaks are weathering remnants of bizarre shapes - shikhans. In the south and southeast, flat coastal accumulative lowlands are typical (Black Sea, Azov, Caspian).
Climate
Far North V.-E. The river, which is located in the subarctic zone, has a subarctic climate. Most of the plain, located in the temperate zone, is dominated by a temperate continental climate with the dominance of western air masses. As the distance from the Atlantic Ocean to the east increases, the continentality of the climate increases, it becomes more severe and dry, and in the southeast, in the Caspian Lowland, it becomes continental, with hot, dry summers and cold winters with little snow. The average January temperature ranges from -2 to -5 °C in the southwest and drops to -20 °C in the northeast. The average temperature in July increases from north to south from 6 to 23–24 °C and up to 25.5 °C in the southeast. The northern and central parts of the plain are characterized by excessive and sufficient moisture, the southern part - insufficient and meager, reaching arid. The most humid part of V.-E. R. (between 55–60°N) receives 700–800 mm of precipitation per year in the west and 600–700 mm in the east. Their number decreases to the north (up to 300–250 mm in the tundra) and to the south, but especially to the southeast (up to 200–150 mm in the semi-desert and desert). The maximum precipitation occurs in summer. In winter, snow cover (10–20 cm thick) lies from 60 days a year in the south to 220 days (60–70 cm thick) in the northeast. In the forest-steppe and steppe, frosts are frequent, droughts and dry winds are characteristic; in the semi-desert and desert - dust storms.
Inland waters
Most of the rivers V.-E. R. belongs to the basins of the Atlantic and North. Arctic Oceans. The Neva, Daugava (Western Dvina), Vistula, Neman, etc. flow into the Baltic Sea; the Dnieper, Dniester, Southern Bug carry their waters to the Black Sea; in the Sea of Azov - Don, Kuban, etc. The Pechora flows into the Barents Sea; to the White Sea - Mezen, Northern Dvina, Onega, etc. The Volga belongs to the basin of internal flow, mainly the Caspian Sea - largest river Europe, as well as the Urals, Emba, Big Uzen, Small Uzen, etc. All rivers are predominantly snow-fed with spring floods. In the southwest of the E.-E.r. rivers do not freeze every year; in the northeast, freeze-up lasts up to 8 months. The long-term runoff modulus decreases from 10–12 l/s per km2 in the north to 0.1 l/s per km2 or less in the southeast. The hydrographic network has undergone strong anthropogenic changes: a system of canals (Volga-Baltic, White Sea-Baltic, etc.) connects all the seas washing the East-E. R. The flow of many rivers, especially those flowing south, is regulated. Significant sections of the Volga, Kama, Dnieper, Dniester, and others have been transformed into cascades of large reservoirs (Rybinsk, Kuibyshev, Tsimlyansk, Kremenchug, Kakhovskoe, and others).
There are numerous lakes of various genesis: glacial-tectonic - Ladoga (area with islands 18.3 thousand km 2) and Onega (area 9.7 thousand km 2) - the largest in Europe; morainic - Chudsko-Pskovskoye, Ilmen, Beloe, etc., estuary (Chizhinsky floods, etc.), karst (Okonskoe Vent in Polissya, etc.), thermokarst in the north and suffusion in the south of V.-E. R. Salt tectonics played a role in the formation of salt lakes (Baskunchak, Elton, Aralsor, Inder), since some of them arose during the destruction of salt domes.
natural landscapes
V.-E. R. - a classic example of a territory with a clearly defined latitudinal and sublatitudinal zonality of natural landscapes. Almost the entire plain is located in the temperate geographical zone, and only the northern part is in the subarctic zone. In the north, where permafrost is common, small areas with expansion to the east are occupied by the tundra zone: typical moss-lichen, grass-moss-shrub (lingonberries, blueberries, crowberries, etc.) and southern shrubs (dwarf birch, willow) on tundra- gley and bog soils, as well as on dwarf illuvial-humus podzols (on sands). These are landscapes that are uncomfortable for living and have a low ability to recover. To the south, a forest-tundra zone with undersized birch and spruce sparse forests stretches in a narrow strip, in the east - with larch. This is a pasture zone with technogenic and field landscapes around rare cities. About 50% of the territory of the plain is occupied by forests. Zone of dark coniferous (mainly spruce, and in the east - with the participation of fir and larch) European taiga, swampy in places (from 6% in the southern to 9.5% in the northern taiga), on gley-podzolic (in the northern taiga), podzolic soils and the podzols are expanding towards the east. To the south there is a subzone of mixed coniferous-broad-leaved (oak, spruce, pine) forests on soddy-podzolic soils, which extends most widely in the western part. Pine forests on podzols are developed along the river valleys. In the west, from the coast of the Baltic Sea to the foothills of the Carpathians, a subzone of broad-leaved (oak, linden, ash, maple, hornbeam) forests stretches on gray forest soils; forests wedged out to the Volga valley and have an insular distribution in the east. The subzone is represented by forest-field-meadow natural landscapes with a forest cover of only 28%. Primary forests are often replaced by secondary birch and aspen forests, which occupy 50–70% of the forest area. The natural landscapes of the opal areas are peculiar - with plowed flat areas, the remains of oak forests and a ravine-beam network along the slopes, as well as woodlands - swampy lowlands with pine forests. From the northern part of Moldova to Southern Urals a forest-steppe zone stretches with oak forests (mostly cut down) on gray forest soils and rich forb-grass meadow steppes (some sections are preserved in reserves) on chernozems, which make up the main fund of arable land. The share of arable land in the forest-steppe zone is up to 80%. Southern part of V.-E. R. (except the southeast) is occupied by forb-feather grass steppes on ordinary chernozems, which are replaced to the south by dry fescue-feather grass steppes on dark chestnut soils. Most of the Caspian lowland is dominated by grass-wormwood semi-deserts on light chestnut and brown desert-steppe soils and wormwood-saltwort deserts on brown soils in combination with solonetzes and solonchaks.
Ecological situation
V.-E. R. has been mastered for a long time and significantly changed by man. Many natural landscapes are dominated by natural-anthropogenic complexes, especially in the steppe, forest-steppe, mixed and broad-leaved forests (up to 75%). Territory V.-E. R. highly urbanized. The most densely populated areas (up to 100 people/km 2) are the zones of mixed and broad-leaved forests of the Central region of V.-E. r., where territories with a relatively satisfactory or favorable ecological situation occupy only 15% of the area. Particularly tense ecological situation in major cities and industrial centers (Moscow, St. Petersburg, Cherepovets, Lipetsk, Voronezh, etc.). In Moscow, emissions in atmospheric air amounted (2014) to 996.8 thousand tons, or 19.3% of the emissions of the entire Central Federal District (5169.7 thousand tons), in the Moscow Region - 966.8 thousand tons (18.7%); in Lipetsk region emissions from stationary sources reached 330 thousand tons (21.2% of the district's emissions). In Moscow, 93.2% are emissions from road transport, of which carbon monoxide accounts for 80.7%. The largest number emissions from stationary sources were noted in the Komi Republic (707.0 thousand tons). The share of residents (up to 3%) living in cities with high and very high levels of pollution is decreasing (2014). In 2013, Moscow, Dzerzhinsk, Ivanovo were excluded from the priority list of the most polluted cities of the Russian Federation. The centers of pollution are typical for large industrial centers, especially for Dzerzhinsk, Vorkuta, Nizhny Novgorod and others. Oil products polluted (2014) soils in the city of Arzamas (2565 and 6730 mg/kg) of the Nizhny Novgorod region, in the city of Chapaevsk (1488 and 18034 mg/kg) of the Samara region, in the regions of Nizhny Novgorod (1282 and 14000 mg /kg), Samara (1007 and 1815 mg/kg) and other cities. Spills of oil and oil products as a result of accidents at oil and gas production facilities and main pipeline transport lead to a change in soil properties - an increase in pH to 7.7–8.2, salinization and the formation of technogenic solonchaks, and the appearance of microelement anomalies. In agricultural areas, soils are contaminated with pesticides, including banned DDT.
Numerous rivers, lakes, and reservoirs are heavily polluted (2014), especially in the center and south of East-East. r., including the rivers Moscow, Pakhra, Klyazma, Myshega (Aleksin), Volga, etc., mainly within the cities and downstream. Fence fresh water(2014) in the Central Federal District amounted to 10,583.62 million m 3; the volume of household water consumption is the largest in the Moscow region (76.56 m 3 / person) and in Moscow (69.27 m 3 / person), the discharge of polluted wastewater is also maximum in these subjects - 1121.91 million m 3 and 862 .86 million m 3, respectively. The share of polluted wastewater in the total volume of discharges is 40–80%. The discharge of polluted waters in St. Petersburg reached 1054.14 million m 3 or 91.5% of the total volume of discharges. There is a shortage of fresh water, especially in the southern regions of V.-E. R. The problem of waste disposal is acute. In 2014, 150.3 million tons of waste were collected in the Belgorod Region - the largest in the Central Federal District, as well as disposed waste - 107.511 million tons. Leningrad region over 630 quarries with an area of more than 1 hectare. Large quarries remain in the Lipetsk and Kursk regions. The main areas of logging and timber processing industry are located in the taiga, which are powerful pollutants of the natural environment. There are clear cuttings and over-cutting, littering of forests. The share of small-leaved species is growing, including in the place of former arable lands and hay meadows, as well as spruce forests, which are less resistant to pests and windblows. The number of fires has increased, in 2010 more than 500 thousand hectares of land burned. Secondary swamping of territories is noted. The number and biodiversity of the animal world is declining, including as a result of poaching. In 2014, 228 ungulates were poached in the Central Federal District alone.
For agricultural lands, especially in the southern regions, soil degradation processes are typical. The annual washout of soils in the steppe and forest-steppe is up to 6 t/ha, in some places 30 t/ha; the average annual loss of humus in soils is 0.5–1 t/ha. Up to 50–60% of the lands are prone to erosion, the density of the ravine network reaches 1–2.0 km/km2. The processes of siltation and eutrophication of water bodies are growing, and the shallowing of small rivers continues. Secondary salinization and flooding of soils is noted.
Specially protected natural areas
Numerous nature reserves, national parks and reserves have been created to study and protect typical and rare natural landscapes. In the European part of Russia there are (2016) 32 reserves and 23 national parks, including 10 biosphere reserves (Voronezh, Prioksko-Terrasny, Central Forest, etc.). Among the oldest reserves: Astrakhan Nature Reserve(1919), Askania-Nova (1921, Ukraine), Bialowieza Forest(1939, Belarus). Among the largest reserves is the Nenets Reserve (313.4 thousand km 2), and among national parks- Vodlozersky National Park (4683.4 km 2). Native taiga plots "Virgin Komi Forests" and Belovezhskaya Pushcha are on the list world heritage. There are many nature reserves: federal (Tarusa, Kamennaya steppe, Mshinsky swamp) and regional ones, as well as natural monuments (Irgiz floodplain, Rachey taiga, etc.). Natural parks have been created (Gagarinsky, Eltonsky, etc.). The share of protected areas in different subjects varies from 15.2% in the Tver region to 2.3% in the Rostov region.
RUSSIAN PLAIN
2. CLIMATIC FEATURES OF NATURAL ZONES
RUSSIAN PLAIN
CONCLUSION
BIBLIOGRAPHY
INTRODUCTION
The East European (Russian) Plain occupies the eastern part of Europe. This is one of the largest plains in the world in terms of area: from north to south, it occupies the space between the coast of the Arctic Ocean and the coast of the Black and Caspian Seas. From west to east, it extends from the western state border to the Urals. On the surface of the plain there is a significant part of the Russian Federation, Ukraine, Moldova, Belarus, Lithuania, Latvia and Estonia, as well as the western part of Kazakhstan.
Among all the plains of our country, only it goes to two oceans. It belongs to the large natural-territorial complexes of Eurasia, located within Russia.
Researchers define the Russian Plain as a physical and geographical country (4;120). The basis for its determination in such a rank are:
hilly, elevated, stratified plain formed on the plate of the ancient East European platform;
Atlantic-continental, predominantly moderate and insufficiently humid climate, formed largely under the influence of the Atlantic and Arctic Oceans;
clearly defined natural areas, whose structures were influenced by the flat relief and neighboring territories - Central Europe, North and Central Asia.
The climate is one of the most important physical and geographical characteristics of the territory. Climate is a long-term weather regime characteristic of a particular area on Earth. (2; 305) At the same time, a long-term regime is understood as the totality of all weather conditions in a given area over a period of several decades; typical annual change of these conditions and possible deviations from it in individual years; weather combinations characteristic of its various anomalies (droughts, rainy periods, cooling, etc.).
1.GENERAL CHARACTERISTICS OF THE CLIMATE
RUSSIAN PLAIN
The climate of the Russian Plain is influenced by its position in temperate and high latitudes, as well as by the connection of the territory (Western Europe and North Asia) and water areas (the Atlantic and Arctic oceans). (4; 128)
The East European Plain is located in temperate and high latitudes, where seasonal differences in the arrival of solar radiation are especially large. The distribution of radiation over the territory of the plain changes dramatically with the seasons. In winter, radiation is much less than in summer, and more than 60% of it is reflected by the snow cover. The radiation balance in winter, with the exception of the extreme southern regions, is negative. It falls in the direction from the southwest to the northeast and depends mainly on the amount of cloudiness. In summer, the radiation balance is positive everywhere. It reaches its greatest value in July in the south of Ukraine, in the Crimea and the Sea of Azov. The total solar radiation increases from north to south from 66 to 130 kcal/cm2 per year. In January, the total solar radiation at the Kaliningrad-Moscow-Perm latitude is 50, and the Ciscaucasia and the southeast of the Caspian lowland are about 150 MJ/m2.
All year round, the western transport of air masses dominates over the East European Plain, and the Atlantic air of temperate latitudes brings coolness and precipitation in summer, and warmth and precipitation in winter. When moving east, it transforms: in summer it becomes warmer and drier in the surface layer, and colder in winter, but also loses moisture. During the cold season, from 8 to 12 cyclones come from different parts of the Atlantic to the East European Plain. When they move to the east or northeast, there is a sharp change in air masses, contributing to either warming or cooling. With the arrival of southwestern cyclones (Atlantic-Mediterranean), and there are up to six of them in a season, warm air of subtropical latitudes invades the south of the plain. Then in January the air temperature can rise to +5 ° -7 ° С and, of course, thaws come.
The arrival of cyclones from the North Atlantic and the southwestern Arctic to the Russian Plain is associated with the intrusion of cold air. It enters at the rear of the cyclone, and then the arctic air penetrates far to the south of the plain. Arctic air enters freely over the entire surface and along the eastern periphery of anticyclones moving slowly from the northwest. Anticyclones often recur in the southeast of the plain, due to the influence of the Asian High. They contribute to the intrusion of cold continental air masses of temperate latitudes, the development of radiative cooling in cloudy weather, low air temperatures, and the formation of a thin, stable snow cover.
In the warm period of the year, from April, cyclonic activity proceeds along the lines of the Arctic and Polar fronts, shifting to the north. Cyclonic weather is most typical for the northwest of the plain, so cool sea air from temperate latitudes often comes to these areas from the Atlantic. It lowers the temperature, but at the same time it heats up from the underlying surface and is additionally saturated with moisture due to evaporation from the moistened surface.
Cyclones contribute to the transfer of cold air, sometimes arctic, from the north to more southern latitudes and cause cooling, and sometimes frost on the soil.
mi (6-12 per season) is associated with the invasion of the plain of humid warm tropical air, which penetrates even into the forest zone. Very warm but dry air is formed in the cores of the spur of the Azores High. It can contribute to the formation of arid types of weather and droughts in the southeast.
The position of the January isotherms in the northern half of the Russian Plain is almost meridional, and in the southeastern part they deviate to the southeast. In winter, heat comes from the Atlantic Ocean and therefore the differences in the climate of the northern and southern parts the plains are smaller than in the western and eastern. Within the northern half of the European part of Russia, the average January temperature varies from west to east from -10 to -20°C, and the deviation of isotherms to the north is mainly due to cyclonic activity, during which Atlantic air is transported to the mainland. In the southern half, the isotherms deviate less from the parallels and the temperature gradient is directed to the northeast. The winter temperature here is much higher than in the north, but it also decreases from west to east: from 5 to -15°C. In summer, almost everywhere on the plain, the most important factor in the distribution of temperature is solar radiation, so isotherms, unlike winter, are located mainly in accordance with geographical latitude. In the Far North, the average July temperature rises to +8°C, which is associated with the transformation of the air coming from the Arctic. The average July isotherm + 20 ° С goes south of Kyiv, through Voronezh to Cheboksary, approximately coinciding with the border between the forest and the forest-steppe, and the isotherm + 24 ° С crosses the Caspian Lowland.
The distribution of precipitation over the territory of the Russian Plain is primarily dependent on circulation factors. Cyclonic activity is observed mainly in the west, in the area of the Barents Sea. On the mainland, atmospheric pressure is distributed in such a way that Arctic and Atlantic air flows into the plain, with which large clouds and significant precipitation are associated. The western transfer of air masses prevailing here is intensified due to the frequent recurrence of cyclones of the Arctic and Polar fronts. Especially often cyclones move from west to east between 55-60°N. sh. (Baltic, Valdai, upper reaches of the Dnieper). This strip is the most humid part of the Russian Plain: the annual precipitation here reaches 600-700 mm in the west and 500-600 mm in the east.
Winter cyclonic precipitation forms a snow cover 60-70 cm high, which lies up to 220 days a year, to the south-west, the duration of snow cover is reduced to 3-4 months a year, and its average long-term height is reduced to 10-20 cm. as we move deeper into the mainland, cyclonic activity and the western transport associated with it in the south of the East European Plain weakens. Instead, the frequency of anticyclones increases. Under the conditions of stable anticyclones, the processes of transformation of air masses intensify, as a result of which humid western air is quickly transformed into continental air. Because of this, precipitation in the southern part of the plain falls 500-300 mm per year, and their amount rapidly decreases in the southeast direction to 200 mm and in some places less. The snow cover is thin and lies for a short time: 2-3 months in the southwest. Relief influences the increase in annual precipitation. For example, 450 mm of precipitation falls in the Donetsk Ridge, and 400 mm in the surrounding steppe. The difference in the annual amount of precipitation between the Volga Upland and the low-lying Trans-Volga region is about 100 mm. In the southern half of the plain, the maximum precipitation occurs in June, and in the middle lane - in July. The southern half is characterized by the lowest and the northern half by the highest relative humidity. The moisture index in the north of the territory is more than 0.60, and in the south 0.10.
Precipitation practically falls from all air masses, but most of it is associated with the Atlantic air of temperate latitudes. Tropical air brings a lot of moisture to the southwest. Precipitation is mainly due to the circulation of air masses on the Arctic and Polar fronts, and only 10% of them are produced by intramass processes in the summer.
The degree of moistening of the territory is determined by the ratio of heat and moisture. It is expressed by various values: a) moisture coefficient. On the East European Plain, it reaches values from 0.55 (the Crimean plains) to 1.33 or more (in the Pechors-
which lowlands); b) dryness index - from 3 (in the deserts of the Caspian lowland) to 0.45 (in the tundra of the Pechora lowland); c) the average annual difference in precipitation and evaporation (mm). In the northern part of the plain, moisture is excessive, since precipitation exceeds evaporation by 200 mm or more. In the zone of transitional moisture from the upper reaches of the Dniester, Don and the mouth of the Kama, the amount of precipitation is approximately equal to evaporation, and the further south from this zone, the more and more evaporation exceeds precipitation (from 100 to 700 mm), i.e. insufficient moisture sets in.
B. P. Alisov, taking into account the radiation balance and atmospheric circulation (transport of air masses, their transformation, cyclonic activity), distinguishes three climatic regions in the European part:
northern Atlantic-Arctic. The influence of the Atlantic Ocean and the Arctic is most noticeable in the region. The southern border runs from Lake Ladoga to the upper reaches of the Pechora. In winter, this territory is characterized by the transfer of air masses and cyclonic activity on the Arctic front. In summer, the arctic air gradually warms up and transforms. In winter, the north of the East European Plain is filled with predominantly continental air. The weather in continental air is frosty (-15°C and below), cloudy, no precipitation. However, in the first half of winter, the Atlantic air prevails, and in the second - the Arctic, so February and March are often colder than January. Summer - July and August; during these months, the arctic sea air, warming up and moistening, transforms into continental air;
middle atlantic-continental region. This area is characterized by cyclonic activity and associated occurrences of Atlantic air masses that transform into continental air. The southern border of the region goes from the middle reaches of the Dniester to the middle Volga. In winter, the transport of Atlantic air dominates. Therefore, winter isotherms are located perpendicular to warm currents, i.e., from northwest to southeast. Arctic air intrusions are observed twice as rarely as in the northern region. In winter, it is usually frosty, somewhat windy, overcast or cloudy. Atlantic air brings a sharp warming, sometimes to a thaw, continuous low clouds and precipitation. Summer, lasting three months (June, July, August), is moderately warm; dominated, as a rule, continental air;
southern continental region. This is the area of transformation of air masses. In winter, continental air is formed here from the Atlantic and Arctic air masses, in summer - warm continental air. The region has the most continental climate in winter: when the spur of the Asian anticyclone spreads, East European continental air forms here. The January isotherms in the southern continental region deviate less from the latitudinal position compared to the first two regions. In summer, the continental region is often located in the zone of high pressure of the spur of the Azores anticyclone. The region is characterized by droughts and dry winds. Drought is a prolonged hot period, characterized by the absence or lack of precipitation necessary for the flow of water from the soil into the plants. Droughts are the result of warming and drying of the air during the transformation of the Arctic air masses over the continent. In many cases, droughts begin in May and take over the entire growing season.
The fight against drought and dry winds provides for a system of agrotechnical measures to improve the structure of the soil and increase the moisture reserves in the soil through snow retention. The planting of forest belts leads to a weakening of drought and dry winds. Forest belts slow down surface runoff, promote snow retention, weaken wind speed and thereby reduce evaporation of moisture from the surface of plants and soil. In addition, forest strips give a significant increase in timber. When planting forest strips, it must be taken into account that their incorrect location leads to large snow accumulation within the forest strip and to dehydration of the fields between the strips.
The construction of ponds and reservoirs, as well as large hydraulic structures, provides irrigation and water supply to areas subject to drought.
B. P. Alisov subdivides the listed regions in the meridional direction into western and eastern regions. AT western regions processes associated with the Atlantic predominate, in the eastern regions the influence of the continent manifests itself. The border runs along the meridian of the Northern Dvina - the upper reaches of the Volga - the mouth of the Dnieper.
2. CLIMATIC FEATURES OF NATURAL ZONES
RUSSIAN PLAIN
Natural zones are clearly expressed on the Russian Plain: tundra and forest-tundra, forest, forest-steppe, steppe, semi-desert and desert.
Tundra and forest-tundra zones - humid, moderately cold - occupy the coast of the Barents Sea, on the moraine-sea plain in the subarctic climate zone. The entire Kanin Peninsula is covered by tundra south to 67°N. sh. Further, the border goes to Naryan-Mar and to the Polar Urals. To the south, a narrow strip (30-40 km) of forest-tundra stretches.
The European tundra and forest tundra are the warmest and wettest in Russia, because they are influenced by the Atlantic Ocean, the non-freezing part of the Barents Sea, the spur of the Icelandic Low in winter and frequent cyclones. This is reflected in the distribution of winter temperatures (the average January temperature near the Kanin Peninsula is -10 °С, and near the Yugorsky Peninsula -20 °С), annual precipitation (600 mm in the west of the tundra, and 600-500 mm in the east), and the duration of freeze-up ( 6-7 months), the highest temperatures of permafrost (from 0° to -3°), which was formed later in the already accumulated marine, glacial, water-glacial, delta, river and lake sediments.
The forest zone is excessively and moderately humid, moderately warm. To the south of the forest-tundra, a forest zone extends in a strip of 1000-1200 km. Its southern border runs approximately north of Lvov to Zhitomir - Kyiv - Kaluga - Ryazan - Kazan - Saratov. The forest zone of the East European Plain is divided into two subzones: taiga and mixed forests. The border between them is drawn along the line St. Petersburg - Novgorod - Yaroslavl - Gorky-Kazan. In the southwest, the taiga merges with the subzone of mixed forests, and in the southeast, with the forest-steppe zone.
The taiga of the Russian Plain differs from the Siberian taiga in its geographical position and history of the development of the territory. The proximity to the Atlantic Ocean and the warmest sector of the Arctic predetermined the development of the Pleistocene powerful multiple ice sheet, a temperate continental climate, which promotes the spread of both more heat-loving - European plants and animals, and more cold-loving - Siberian. The European taiga receives more precipitation than the West Siberian taiga. Their annual number on the plains is more than 600 mm, and on the uplands - up to 800 mm. The entire subzone of excessive moisture, since precipitation exceeds evaporation by 200 mm.
The European taiga is divided into northern taiga, middle taiga and southern taiga forests.
The northern taiga is characterized by excessive moisture. In its western part, winters are snowy and moderately cold, and in its eastern part, winters are cold and quite snowy. The agro-climatic characteristics are as follows: the depth of soil freezing is 120 cm, the duration of the growing season above + 10 ° is 65 days, the sum of active temperatures is 800-1200 ° C, i.e. this is an agro-climatic territory of early vegetable crops with reduced heat requirements.
The middle taiga is characterized by excessive moisture, moderately cold and cold snowy winters. The agro-climatic characteristics of the territory are as follows: the duration of the growing season is 100 days, the depth of soil freezing is 70 cm, the sum of active temperatures is 1200-1500 ° C, which corresponds to the early crops of the temperate zone (gray bread, legumes, potatoes, flax, and other crops).
The southern taiga is also quite humid, but has significant differences in winter temperatures (the average January temperature in the west is -6 ° C, and in the east -13 ° C), soil freezing in the west is 30 cm, and in the east 60 cm or more. The sum of active temperatures is 1900-2400°C.
The climate becomes warmer to the south, the amount of precipitation is almost equal to evaporation and therefore the moisture coefficient approaches unity, coniferous trees become rare and give way to broad-leaved trees.
The agro-climatic characteristic of the western part of moist broad-leaved forests is as follows: the sum of active temperatures is 2200 - 2800 ° C, i.e., this is the territory where crops of the temperate zone are cultivated (corn for grain, sunflower for seeds, soybeans, rice, sugar beet).
On the Central Russian Upland and in Meshchera, the climate is more continental: winters are colder and longer, the occurrence and depth of snow cover increase, and summers are warmer and drier.
Forest-steppe zone - moderately humid and moderately warm located in the south of the Atlantic-continental climatic region
temperate zone of the East European Plain. Its southern border runs approximately from Chisinau to Dnepropetrovsk, south of Kharkov - Saratov to the Samara valley. South of this line, among the steppes, there are "islands" of forests. They arose in elevated moist areas - this is the Donetsk ridge among the steppes of Ukraine, forest Codri among the steppes of Moldova. So, for example, Kodry has a height of more than 400 m, and precipitation is 500 mm (100-150 mm more than the Belets meadow steppe, located to the north).
The forest-steppe stretches from the southwest to the northeast and, consequently, occupies the southernmost position among all zones in the west of the plain. This determined its bioclimatic features: in the western part to the meridian of Voronezh, it belongs to a semi-humid, and to the east - to a semi-arid climate with a depleted vegetation cover. Winter here is moderately cold, snowy, the average temperature is 10-12° lower than in Ukraine.
Summer can be very warm and even hot, the maximum temperature reaches + 40 °, there is little precipitation, droughts and dry winds develop. This type of weather has a detrimental effect on the development of natural and cultivated vegetation. Summer can be moderately warm with sufficient moisture, when annual precipitation can reach up to 800 mm. In the forest-steppe there is an important bioclimatic zero zone of the ratio of precipitation and evaporation: to the north of it, precipitation is 100-200 mm more than evaporation, and to the south - 100-200 mm less than evaporation.
The steppe zone - not sufficiently humid and very warm - extends from the forest-steppe to the Black Sea-Azov coast and then goes to the foothills of the Crimea and the Caucasus. It reaches its greatest width in the middle part of the East European Plain, near the 40th meridian. Its northern border in the west descends far to the south, and in the east it rises sharply to the north.
There is a lot of heat in the steppe in summer: the average temperature in July is everywhere 21-23 ° C, the sum of air temperatures above + 10 ° reaches 2600-3200 °. In winter, there are big differences in weather types and temperatures in the west and east: the average January temperature in the warm Ukrainian and Moldavian steppes is only 2-4 °C. Mediterranean cyclones are frequent there, and they bring tropical air with a temperature of -2 ° -6 ° С. The eastern, trans-Volga, steppes are cold in winter, as anticyclonic weather prevails here and the average January temperature reaches -14 -16 ° С. Therefore, the sum of negative temperatures during the snow cover in the west is only 200-400 ° C, and in the east it increases to 1000-1500 °. Moisture in the steppes is not enough: the western steppes receive 600 mm of annual precipitation, and 500 mm in the Middle Volga region. But at high temperature air evaporation in the steppes exceeds the amount of precipitation by 200-400 mm, which leads to insufficient moisture. In addition, dry winds are frequent (in the west their number reaches 10-15, and in the east - 20-30).
The northern steppes are less warm, but more humid than the southern ones.
Semi-desert and desert zones of the Russian Plain - moderately dry and very warm - are located in the lower reaches of the Volga, and beyond the Volga stretch to Aktyubinsk. The continental East European climatic region is the westernmost desert region. It is characterized by an annual radiation balance of 1800 - 2000 MJ / m2, annual precipitation - 300-400 mm, evaporation exceeds precipitation by 400-700 mm, the sum of active temperatures - 2800-3400 C. All these climatic values confirm the dryness and warmth of the territory. Winters are cool - negative temperatures prevail: the average January temperature in the southwest is - 7 C, and in the northeast ---15 C, the duration of the snow cover is 60 and 120 days, respectively, and during this time the sum of negative temperatures is about 300 C in the southwest and 1400 C - in the northeast of the European semi-desert. With such a reserve of winter cold, the soil freezes in the semi-desert and desert to a depth of 80 cm (approximately the same amount as in the middle taiga).
CONCLUSION
Thus, as a result of our study, we can draw the following conclusions.
Taking into account the peculiarities of the radiation regime and atmospheric circulation (transport of air masses, their transformation, cyclonic activity), two climatic zones should be distinguished on the territory of the Russian Plain - subarctic and temperate, and within them - five climatic regions. In all areas there is an increase in the continentality of the climate to the east. This is due to the fact that processes associated with the Atlantic and more active cyclogenesis predominate in the western regions, while the influence of the continent affects the eastern regions. This regularity in climate change is a manifestation of sectorality.
Differences in the climate of the East European Plain affect the nature of the vegetation and the presence of a fairly clearly expressed soil-vegetation zonality.
BIBLIOGRAPHY:
1. Alisov B.P. Climate of the USSR. M., 1969.
2. Great Soviet Encyclopedia. T. 12. M., 1973. Article "Climate".
3. Gvozdetsky N.A., Mikhailov N.I. Physical geography of the USSR. M.: 1982.
4 . Davydova M.I., Rakovskaya E.M., Tushinsky G.K. Physiography THE USSR. M., 1989.
5. Makunina A.A. Physical geography of the USSR. M., 1985.
6. Myachikova N.A. Climate of the USSR. M.: 1983.
7. Tushinsky G.K., Davydova M.I. Physical geography of the USSR. M., 1976.
The relief of the Russian Plain is more diverse in the northwest, in the region of the last glacier. The main terminal moraine belt enters here from the southwest. It stretches to Lake Onega and further - to the lower reaches of the Northern Dvina and to the Mezen Bay. It is characterized by a hilly-morainic relief with many lakes. The heights of the Valdai, Veps and other uplands of the main belt in the Carboniferous Plateau reach 300 m.
To the west of the main belt, moraine ridges are located in the form of discontinuous hills; characteristic are kams and flat low-lying plains - Volkhovsko-Ilmenskaya and others. During the retreat of the glacier, huge dammed lakes formed in these areas. The deepest sections of the ancient lake basins are now occupied by large lakes - Ilmen, Chudskoye and Pskovskoye. A flat limestone Ordovician plateau stretches along the Gulf of Finland and Lake Ladoga, on which karst is developed.
A different relief was formed in the area between the main terminal moraine belt and Timan. The landforms created here by the early glaciations are eroded. Interfluve plateaus have a flat and undulating surface. Spacious lowlands with river valleys of the Northern Dvina and other rivers, dividing the plateau, merge in the north with the coastal lowland. The ancient Timan ridge is poorly expressed in the relief: it consists of several flat ridges - "stones" with hilly remnants of hard rocks. The northwestern extension of Timan is the low and flat Pae Range on the Kanin Peninsula. In the southeast, Timan comes close to the spurs of the Urals - Polyudov stone. The Pechora basin between the Timan and the Urals is characterized by undulating, in places hilly plains, dissected by lowlands with river valleys. On the Bolshezemelskaya and Malozemelskaya plains there are moraine hills and ridges - Musyurs.
The relief of the Polar and Northern Urals is extremely diverse. Mountain ranges and massifs are separated there by deep tectonic depressions and river valleys. Glaciation in the Urals was accompanied by the formation of pointed ridges, troughs, the accumulation of moraine and water-glacial deposits in valleys and at the foot of mountains, and the smoothing of slopes.
The highest peaks of the Northern Urals are characterized by sharp (alpine) forms: narrow ridges, peaks. As a result of frosty weathering, placers (kurums) of large stone blocks and rock fragments near the peaks and on the slopes of high ridges are very typical for the Ural Mountains. There are no sharp fluctuations in elevation on the western slope of the Urals, the summit surfaces are wavy in nature, descending, the mountains are replaced in the foothills by wide quartzite uplands - parmas.
The climate features of the European North are primarily due to the position of the region in the temperate and cold zones in the north-west of Eurasia and the large extent of the region from south to north, as well as from east to west on both sides of the Arctic Circle.
From south to north, according to the seasons, lighting and heating conditions change especially strongly in the European North. earth's surface sunbeams- the length of the day and the height of the sun above the horizon, which determine the influx of solar energy (radiation). The midday height of the sun above the horizon on the southern edge of the European North reaches on the day of the summer solstice, June 22, almost 58 °, and the duration of the day is 18 hours. To the north of here, the sun's height decreases, and the length of the day increases, the nights become shorter. Approximately from the latitude of Leningrad, the sun hides behind the horizon shallowly and for a short time, so that the evening dawn merges with the morning one, and white nights reign from late April to mid-August.
At the Arctic Circle on June 22, the day lasts around the clock. Under 70 ° with. sh. the sun does not set from May 20 to July 23, and on Franz Josef Land - over four months. During this period of the polar day, the sun here, not rising high above the horizon, "walks in a circle."
The polar day and beyond the polar circle are preceded by bright, twilight nights; at 70° N sh. they start already on March 30, and after the polar day they continue until September 12.
With the end of bright nights, the days become shorter and the height of the midday sun decreases. In the middle of winter, even in the south of the region, the sun rises only to 11 °, and the day lasts only 6 hours and 30 minutes.
At the Arctic Circle and north of it, the sun does not appear above the horizon at all.
The duration of the polar night, as well as the polar day, is not the same in different latitudes (at the Arctic Circle - 24 hours, at 70 ° N - 64 days, on Franz Josef Land - more than 130 days). In the winter months, the influx of solar heat in the European North is small everywhere, and where the polar night reigns, its flow completely stops.
In general, for the year at the southern border of the European North, the influx of solar energy by "/h, on the coast of the Barents Sea is almost half and in the Far North in the Arctic almost 2 times less than in the south of the Russian Plain, off the coast of the Black Sea.
Atmospheric circulation has a great influence on the climate. In the European North, these influences are very pronounced due to the position of the territory in the north-west of Eurasia - in the zone of active cyclonic activity and frequent changes in air masses, different in their place of formation, temperature and humidity.
Throughout the year, western air currents prevail here. Cyclones move mainly from the North Atlantic to the Barents Sea. Cyclonic activity is especially intense in autumn and winter. In winter, the entry of warm and humid Atlantic air is accompanied by warming, snowfalls, and during thaws, sometimes rain. In summer, when cool air comes in from the west, temperatures drop, cloudiness increases, and heavy rains fall. Moving over land further to the east, humid Atlantic air is converted into continental air (it cools in winter and warms up in summer).
From the northeast, from the side of the Kara Sea, less often from the northwest or from the north, Arctic air invades the territory of the European North. Arctic air coming from the northeast forms above the ice. This "Kara" Arctic air is much colder and drier than the Arctic air coming from the northwest and passing a long way over the relatively warm waters of the ocean. The intrusion of arctic air occurs more often in summer, but it brings strong drops in air temperature in winter, especially in the second half and at the end of winter. With the advent of arctic air, frosty weather sets in in winter, and cool in summer.
Moving inland, the Arctic air warms up and transforms into continental air. In winter from the east, and in summer from the southeast, continental air from temperate latitudes enters the European North. In winter it is very cold and dry, in summer it is dry and warm.
Spreading, it brings clear, frosty weather in winter, dry and warm in summer.
Sometimes in summer, from the southwest, maritime subtropical air, warm and very humid, spreads to the territory of the European North. It covers mainly only the southwestern regions. With the advent of this air, heavy rains fall, but then, usually for a short time, clear, warm or even hot weather sets in. Even rarer and only in summer Central Asia and other southeastern regions comes continental dry and hot tropical air.
It brings briefly very warm, dry, windless weather.
Huge masses of heat coming with the Atlantic air cause a positive temperature anomaly characteristic of the European North (the average air temperatures here are higher than the average for these latitudes).
Frequent changes in air masses, as well as cyclones, cause unstable weather typical of the European North.
The winds here are also changeable. In the northern strip of this region, northern winds dominate in summer, and southern and southwestern winds dominate in winter.
The coldest month almost everywhere in the European North is January (in the southwest and extreme northwest - February). The lowest average January temperatures (-22°) are observed in the northeast of the mainland of the European North and on the eastern side of Novaya Zemlya, the highest (-6°) and slightly higher - in the southwestern regions and under the warming influence of the sea in the far north -west, in the coastal strip of the Kola Peninsula.
The absolute minimum temperature in areas far from the sea reaches -55° in the European North and is below -35, -40° everywhere.
The warmest month in the European North is July. The average July temperatures are highest in the south (+18, +19°), the lowest - in the northeast of the continental part of the European North (+8°). Temperatures are even lower on the islands of Novaya Zemlya (+5°) and on Franz Josef Land (0°). The highest (maximum) daily temperatures (above +36°) were observed in July in different parts of the European North.
The duration of the period with stable temperatures above +5°, which determine the timing of sowing and harvesting crops, within the temperate zone varies in the European North from 180-150 days in the south, to 110-80 days in the north. The possibilities of growing agricultural plants also depend on the availability of heat during the growing season.
The indicator of security is the sum of stable average temperatures above 10 °. In the southern regions of the European North, the sums of temperatures above +10° reach almost 2000°, which is sufficient for ripening even late varieties of wheat, potatoes, tomatoes, and flax for fiber. In the northern zone, the sum of temperatures drops to 750-500 °, however, it makes it possible to grow potatoes, vegetables and some grains.
Atlantic air coming from the west brings not only heat, but also a lot of moisture. The annual amount of precipitation on the plains of the European North reaches an average of 500 - 700 mm, in the extreme northeast - only 300 mm, in the mountains of the Urals - more than 800 mm.
Rains and snowfalls are frequent - up to 160 - 200 days a year. Rains are predominantly heavy, drizzling. Summer showers are rare. Although precipitation occurs most often in autumn and winter, most of it occurs during the warm season.
Snow cover within the European North is long, on average 120 days, and in the northeast even 250 days. In the mountains of the Kola Peninsula and the Urals, snow spots remain for several years.
The northern island of Novaya Zemlya, the islands of Franz Josef Land and Victoria Land are almost entirely covered with a thick layer of ice and snow. There are also small glaciers in the Urals.
In the western regions of the European North, due to thaws, the snow is compacted and the thickness of the snow cover is less (30 cm) than in the east (70 - 100 cm).
Due to the considerable thickness of the snow cover, the soils of the European North do not freeze deeply and not strongly, the temperatures of frozen soils are usually only slightly below 0 °. Nevertheless, in the Far North, a layer of permafrost lies already at an insignificant depth. It is more widespread in the east, where the continentality of the climate increases, and less in the west, but nowhere does it form a continuous shell.
A characteristic feature of the climate of the European North is the constant high relative humidity of the air (average 75 - 90%). At low air temperatures and high humidity, evaporation is low everywhere.
Differences in the climate of the European North are reflected in the timing of the onset, duration and temperatures of the seasons.
Winter is the time of the year with daily air temperatures below -5°, stable snow cover.
It begins first in the northeast (at the end of October), and later in the southwest (on average, in the first half of November); winter in the west, and especially in the southwest, is usually mild, with thaws, cloudy, less often frosty, in the east it is more stable, cold and clear, and beyond the Arctic Circle it is dark and twilight, with strong winds and frequent blizzards, with storms at sea . In the extreme northeast, there are up to 100 days with snowstorms. Winds and blizzards are also common in other parts of the European North during intrusions of arctic air masses, when mild cyclonic weather often changes to a thaw, anticyclonic clear, sunny, bright from shining snow, windless and cold weather.
But it doesn’t happen year after year: some winters were with long frosty weather, others with frequent thaws.
Spring begins in the European North almost everywhere in March, in the Far North - in April, and in the northeast - even at the end of April. In March (to the north - in April), announcing the onset of spring, rooks are the first to arrive, in the Far North - snow bunting. In April, a bear leaves its den, waterfowl arrive, and a stork comes to the south-west. In April (to the north - in early May), the first butterflies fly out - urticaria, snowdrops bloom - blueberry, anemone; in the south-west at the beginning of May (in the east - at the end) the first cuckoo is heard, the birch begins to turn green (in the Far North in June), the first song of the nightingale is heard; in the south-west in May (to the north - in June), bird cherry, lilac bloom, winter rye begins to ear. In spring, the influence of the Atlantic weakens, cloudiness decreases, the day becomes longer, the sun rises higher, shines brighter.
With the heating of surface air during the day above zero degrees, there are thaws, and at night it freezes and the snow freezes, an ice crust forms on it - crust. Arctic air intrusions become more frequent, especially in May. In this regard, there are returns of cold weather, when frosts are possible.
The northern spring is protracted and proceeds in different ways. There were years when in Leningrad, for example, on May 1, people went to a festive demonstration in summer clothes, but it happened that on that day the temperature dropped below 0 ° C or a gale was blowing, it was sleet and raining.
Only in June (south of 65 ° N) and July (north of this parallel) does summer come, moderately warm or cool. At this time, lilac blossoms in the southwestern regions of the European North.
The real, full summer comes later, in the second half of June - early July, when the average daily temperatures rise above -15 °, blueberries and raspberries ripen, and the number of edible mushrooms, is haymaking. But north of the 65th parallel, summer is very cool and there is no period with temperatures above 15 ° at all.
In the extreme northeast and on the polar islands, the average air temperature in all summer months is below -\-10 °.
The entry of warm air from the south sometimes raises the temperature to +30. + 35 ° (even on Novaya Zemlya it is above + 20 degrees). On the contrary, the entry of arctic air greatly lowers the temperature (to -2°, in the northeast to -5°).
Frosts are possible almost everywhere in June and August, and in the east, in the northern strip, even in July. Cyclones in summer come more often than in spring, cloudiness increases (especially in the second half), the amount of precipitation increases, there are thunderstorms and showers.
A sign of autumn - yellowing of birch leaves - everywhere in the European north is already noticeable at the end of August. But autumn really comes in September. Arctic air comes less often in autumn, but it gets colder; cyclonic activity intensifies, cloudiness increases. During the period of golden autumn, in September and in the first half of October, with the entry of warm air, "Indian summer" is briefly established - dry, sunny, warm weather.
In deep autumn, until the first snow, the days quickly shorten, cloudiness increases even more, rainy weather happens more often, the departure of waterfowl ends, and rooks fly away. Drizzling rains are replaced by snowfalls, and before the beginning of winter, during the "pre-winter" period, in November, snow cover appears and disappears again.
But in other years already in September (and in some areas in the north and east in August) there were frosts up to -6 ° in the southwest and -18 ° in the east.
