Factors affecting the climate of the Caucasus. North Caucasus: nature and its description

The Caucasus cannot be attributed to one climatic region. To the north of the axial belt of the Greater Caucasus - a temperate climate, in Transcaucasia - subtropical. Within them there are differences due to the nature of the relief, position in relation to air currents, position relative to the Black and Caspian Seas, and local circulation.

The climate of the Caucasus is changing in three directions:

from west to east - in the direction of increasing continentality,

from north to south - in the direction of increasing amounts of radiative heat

in the high-altitude direction - an increase in precipitation and a decrease in temperatures.

Cloudiness plays a special role - with a rise in the mountains and in the western regions of the Caucasus, due to its increase, annual values solar radiation less than average.

AT summer months radiation balance in the Caucasus, it is close to tropical; local VMs are transformed into tropical ones.

Circulation: continental air of temperate latitudes dominates in the North Caucasus, subtropical in Transcaucasia. Alpine zones under the influence of western directions.

During the winter months the territory is located south of the "major axis"; areas of low pressure are formed over the Black and the south of the Caspian. The result is an outflow of dense cold masses of the "great axis" to the Caucasus. However, the mountain wall prevents penetration to the south, it is still possible to bypass along the coasts of the seas - "nords" and "boron". In the west, there is a lot of snow in the mountains. To the east, the influence of southwestern transport weakens and the influence of the Asian anticyclone intensifies, snowfall decreases. A local anticyclone forms over the Armenian Highlands in winter.

AT summer time over Asia they form an area of low pressure. Strengthening western currents sea air temperate latitudes from the North Atlantic, which capture the Caucasus. They give up precipitation on windward slopes. In the second half, the Azorean maximum shifts to the north and often captures the Caucasus.

The role of foehns, mountain-valley winds and breezes, the formation of a center of low pressure over the Armenian Highlands is noticeable. Sea basins moderate the temperature.

In general, the southern slopes are characterized by higher (summer and winter) temperatures. The annual amount of precipitation increases with elevation to the mountains and decreases at all levels from west to east.

The Caucasus is located on the border of the temperate and subtropical zones. The influx of solar radiation is so significant that in the summer a local center for the formation of tropical air masses is created in Transcaucasia. The boundary of the temperate and subtropical belts runs along the axial part of the Greater Caucasus. Radiation balance 2300 MJ / m 2 / year (west) - 1800 (east) MJ / m 2 / year.

In winter, the continental air of temperate latitudes (CLA) spreads to Ciscaucasia from the Voeikov axis. East and northeast winds prevail. Cold air entering Ciscaucasia lingers on the northern slopes of the Greater Caucasus, not rising above 700-800 m. And only in the northwestern part of the Black Sea chain, where the height of the ridges is less than 1000 m, cold air crosses them. Over the Black Sea in winter, a reduced pressure is established, so cold heavy air rushes to it with high speed, literally falling from the mountains. Strong cold winds arise, the so-called Novorossiysk bora. The air temperature during boron drops to -15...-20°С. Bora is observed in the Anapa-Tuapse section.

The upper parts of the mountains are located in the free atmosphere zone, where the prevailing role belongs to the western winds. In winter, the western transport dominates at an altitude of more than 1.5-2 km, and in summer - 3.5-4 km.

The formation of climatic conditions of the cold period is greatly influenced by cyclonic activity developing on the Mediterranean branch of the polar front. The trajectories of the Mediterranean cyclones are directed to the northeast of the Black Sea and cross the Caucasus in its western part. Their advance through the Caucasus leads to tropical air advection, which causes intense thaws, snow cover snow avalanches in the mountains and the formation of foehns on the northern slopes of the Greater Caucasus. With the development of hair dryers, the air temperature can rise to +15...+20°C. As the height of the mountains increases, the absolute maximum temperature decreases in winter and becomes negative at Elbrus station (-2...-3°C).

Frequent advection of heat and the influence of the sea determine the positive average monthly air temperature on the Black Sea coast of the Caucasus. The average January temperature in Novorossiysk is +2°С, in Sochi +6.1°С. In Ciscaucasia, the average air temperature is -1...-2°C in the western regions, dropping to -4...-4.5°C in the center and again rising to the Caspian Sea to -2...0°C. In the mountains, the temperature decreases with height, reaching -12 ... -14 ° C in the highlands, in the area of \u200b\u200bperpetual snow and glaciers.

When cold air masses break through from the north, the temperature in Ciscaucasia can drop to -30...-36°C. Even in Anapa, the absolute minimum is -26°C, and in Sochi - -15°C.

The intensification of cyclonic activity in the cold season causes the winter maximum precipitation on the Black Sea coast of the Caucasus. In the rest of the territory, the maximum precipitation occurs in the summer.

In winter, snow cover sets in on the plains and in the mountains of the Caucasus. It first appears on the plains with relatively warm winter only in the second half of December. In some winters, stable snow cover does not form. Snow falls repeatedly during cooling and melts during thaws. The thickness of the snow cover on the plains is 10-15 cm. On the southwestern slopes of the Greater Caucasus Mountains (Achishkho), due to the abundance of winter precipitation and the decrease in the frequency of winter thaws, the snow thickness reaches 3-4 m. In the mountains of the eastern part of the Caucasus, it is reduced to 1 m (Myachkova N.A., 1983). The number of days with snow cover on the Stavropol Upland is 70-80, decreasing to the west and east of it to 50-40 and increasing in the mountains to 80-110 days due to the long cold period. On the lower border of the highland zone, snow lies 120 days a year.

In the Javakheti-Armenian Highlands, an area of high pressure is formed at this time. From here, the cold continental air of Asia Minor (temperature -12°C) is taken out, penetrating into the middle part of the Riono-Kura corridor, but quickly transforming as it moves east. Colchis is filled with sea air masses of temperate latitudes, coming here with Mediterranean cyclones (t 4-6o). In winter, they constantly cross the Black Sea, where the pressure is low, and, as it were, fall into a trap between the B. and M. Caucasus ranges. The greatest amount of precipitation falls in late summer (August-September), as well as in late autumn - early winter. In other regions of the Caucasus, there is no precipitation at this time, with the exception of the Kuro-Araks lowland. Here, autumn-winter precipitation and partly spring precipitation are associated with a branch of the Iranian polar front, along the line of which cyclonic activity develops. It increases significantly on the slopes of Talysh and along the outskirts of this lowland.

In summer, the formation of the climate in the Caucasus is significantly affected by the frequency of humid Atlantic air masses and dry continental air masses that form over the spaces of the interior regions of Eurasia and come from the east. In connection with this, the importance of the submeridional climate division (the transverse uplift of the Stavropol Upland - the Central Caucasus) is enhanced. On the Black Sea coast of the Caucasus and in the Western Ciscaucasia, the air warms up to 22-23°C. In the highest parts of the Stavropol Upland and in the Mineralovodsky region average temperature July is 20-21°C. In the east of Ciscaucasia, the air warms up to 24-25°C. In the mountains, the air temperature decreases with height, reaching 10°C at an altitude of about 2500 m and 7°C at an altitude of 3000 m. At the Elbrus station (altitude 4250 m), the average July temperature is only 1.4°C.

In the first half of summer in Ciscaucasia, the influence of Atlantic cyclones, which determine the June maximum precipitation, increases. Later, the transformation of air masses over the southeast of the Russian Plain increases, therefore, already in the middle of summer, the amount of precipitation decreases, and conditions are often created for the formation of dry winds and droughts, the frequency of which increases in the east.

The annual amount of precipitation increases from the foothills to the mountains and with the rise up the slopes, but at the same time it noticeably decreases when moving from west to east. On the Kuban-Azov lowland, the annual amount of precipitation is 550-600 mm, on the Stavropol Upland it increases to 700-800 mm and decreases to 500-350 mm in the Eastern Ciscaucasia. On the Black Sea coast, the amount of precipitation increases rapidly from north to south (from 700 mm northwest of Novorossiysk to 1650 mm in the Sochi region). In the highlands of the western part of the Greater Caucasus, 2000-3000 mm of precipitation falls, and in the eastern part - only 1000-1500 mm. The amount of precipitation also decreases in the depression between the Rocky and Lateral Ranges, especially in the "shadow" of the Rocky Range, amounting to 650-700 mm. The largest annual amount of precipitation is observed on the windward southwestern slopes of the Greater Caucasus. At the Achishkho station, it is over 3700 mm per year. It - the largest number precipitation not only in the Caucasus, but throughout Russia.

Average annual precipitation: Colchis, the southern slope of the Western Caucasus - 1.5-2 thousand mm, Western and Middle Ciscaucasia 450-600 mm, Eastern Ciscaucasia, Terek-Kuma lowland -200-350 mm, Kuro-Araks lowland - 200-300 mm, Javakheti-Armenian highland 450-600 mm, Lankaran lowland - 1200 mm. It is warmest in summer in the Kuro-Araks lowland (26-28°C), in the rest of the territory 23-25°C, in the Javakheti-Armenian Highlands 18°C. However, temperature and precipitation are subject to change depending on the height of the mountains, forming altitudinal climatic zonality. So, the average annual temperature on the Black Sea coast is 12-14°С, in the foothills of the Caucasus it is 7-8°С, at an altitude of 2-3 thousand m -3-0°С. In summer, despite the increase in solar radiation with height, the temperature drops by an average of 0.5-0.6 ° C every 100 m, and by 0.3-0.4 ° C in winter. When climbing the mountains, the average annual positive temperature persists only up to a height of 2300-2500 m. On Elbrus it is -10°C. Similar regularities are preserved for average monthly air temperatures. Thus, the average temperature in January in the Ciscaucasia is -2-7 ° С, in the middle and high mountains - from -8 to -13°C; on Elbrus -19°С; in Novorossiysk 3°С, Sochi 5°С. In July, the temperature is 23-25°С everywhere, at an altitude of 2-2.5 thousand m -18°С, 4000 m -2°С.

Quantity precipitation also changes with height. If in the northeastern Ciscaucasia they fall less than 300 m, further to the west 300-400 mm, and in the Western Ciscaucasia 400-500 mm, then already in the low-mountain regions of Stavropol - Nalchik 500-800 mm, at the latitude and height of Vladikavkaz - 800-1000 m (1.5 thousand m), at an altitude of 2 thousand m, an average of 1000-1500 mm; higher the amount of precipitation decreases: Terskol - (3050 m) - 930 mm.

The height of the snow line is 2800-3000 m, in the western part - 3200-3500 m, in the eastern part of the Greater and Lesser Caucasus glaciation is negligible - 3 square meters. km. On B.K. - 1420 km 2, their total number is 2200. Of these, 70% is located on the northern slope, 30% - on the southern. Types of glaciers - mountain-valley (20% of the area), cirque and hanging. Glaciation centers - Elbrus, Kazbek, other peaks of the Central Caucasus in M.K. - Aragats, Zangezur ridge, Javakheti ridge. All glaciers are in retreat (10-20 m/year).

The climate and features of the relief of the Caucasus determine its modern glaciation. Within Russia in the Caucasus there are 1498 glaciers with a total glaciation area of 993.6 km 2, which is 70% of the total number of glaciers and the glaciation area of the Greater Caucasus. The sharp predominance of glaciers on the northern slope is due to orographic features, snow drift westerly winds beyond the barrier of the Dividing Range and somewhat less than on the southern slope, insolation. The snow limit lies at 2800-3200 m in the western part of the Caucasus and rises to 3600-4000 m in the east.

The greatest glaciation is concentrated in the Central Caucasus. The largest massif of modern glaciation is the Elbrus glacial complex (area 122.6 km 2). The two-headed Elbrus is covered with a firn-ice cap about 10 km in diameter, which feeds more than 50 glacial streams radially diverging from it. The largest complex valley glacier in the Caucasus is the Bezengi glacier (length 17.6 km, area 36.2 km 2), located at the foot of the Bezengi wall and feeding the Cherek-Bezengi river. It is followed by the Dykh-Su glaciers (length 13.3 km, area 34.0 km2) and Karaugom (length 13.3 km, area 26.6 km2).

In the Western Caucasus, due to the low height of the mountains, glaciation is small. Its largest areas are concentrated in the Kuban basin near the highest mountain peaks - Dombai-Ulgen, Pshish, etc. The glaciation of the Eastern Caucasus is less significant due to the great dryness of the climate and is mainly represented by small glaciers - cirque, hanging, caro-valley.

total area glaciers - 1965 km 2. greatest development glaciation reaches between Elbrus and Kazbek, from here it gradually decreases to the west and sharply to the east. The most common car and hanging. 20% - valley glaciers. Everyone regresses.

North Caucasus- a huge territory that starts from the Lower Don. It occupies part of the Russian platform and ends with the Great Caucasian ridge. Minerals, mineral waters, developed Agriculture- the North Caucasus is beautiful and diverse. Nature, thanks to the seas and the expressive landscape, is unique. The abundance of light, heat, the alternation of arid and humid areas provides a variety of flora and fauna.

Landscape of the North Caucasus

On the territory of the North Caucasus are Krasnodar and Stavropol region, Rostov region and Kabardino-Balkaria, North Ossetia and Dagestan, Chechnya and Ingushetia. Majestic mountains, endless steppes, semi-deserts, forests make this region so interesting for tourism.

The whole system of mountain ranges is represented by the North Caucasus. Its nature changes with height above sea level. The landscape of the territory is divided into 3 zones:

Mountain.
Foothill.
Steppe (plain).

The northern borders of the region stretch between the rivers Kuban and Terek. There is a foothill region begins to the south, which ends with multiple ridges.

The climate is influenced by the abundance of mountains and the proximity of the seas - Black, Azov, Caspian. which can be found in the North Caucasus, contain bromine, radium, iodine, potassium.

Mountains of the North Caucasus

From icy northern regions the Caucasus, the highest mountains of the country, stretches to the hot southern regions. They formed during

The system is considered a young mountain structure, just like the Apennines, Carpathians, Alps, Pyrenees, Himalayas. Alpine folding is the last epoch of tectogenesis. It led to numerous mountain structures. It is named after the Alps, where the process took its most typical manifestation.

The territory of the North Caucasus is represented by the mountains Elbrus, Kazbek, the Rocky and Pasture Ranges, Cross Pass. And this is only a small, most famous part of the slopes and hills.

The highest peaks of the North Caucasus are Kazbek, the highest point of which is at around 5033 m. And the extinct volcano Elbrus - 5642 m.

Due to the complex geological development, the territory and nature of the mountains of the Caucasus are rich in gas and oil deposits. Mining takes place there - mercury, copper, tungsten, polymetallic ores.

The accumulation of mineral springs, different in their own way chemical composition and temperature, can be found in this territory. The extraordinary usefulness of the waters led to the question of creating resort areas. Zheleznovodsk, Pyatigorsk, Kislovodsk are widely known for their springs and sanatoriums.

The nature of the North Caucasus is divided into humid and arid regions. The main source of precipitation is the Atlantic Ocean. That is why the foothill areas of the western part are sufficiently moistened. While the eastern region is prone to black (dusty) storms, dry winds, and drought.

Features of the nature of the North Caucasus are in the diversity of air masses. In all seasons, the cold dry stream of the Arctic, the wet stream of the Atlantic, and the tropical stream of the Mediterranean can penetrate the territory. Air masses, replacing each other, carry diversity weather conditions.

On the territory of the North Caucasus, there is also a local wind - foehn. Cold mountain air, descending, gradually heats up. Already a hot stream reaches the earth. This is how the wind fen is formed.

Often cold air masses penetrate through go around it from the east and west sides. Then a cyclone reigns on the territory, detrimental to the heat-loving flora.

Climate

The North Caucasus is located on the very border of the temperate and subtropical zones. This gives the climate softness and warmth. A short winter that lasts about two months long summer- up to 5.5 months. The abundance of sunlight in this area is due to the same distance from the equator and the pole. Therefore, the nature of the Caucasus is characterized by riot and brightness of colors.

Falls in the mountains a large number of precipitation. This is due to the fact that the air masses, lingering on the slopes and rising up, cool, give off moisture. Therefore, the climate of the mountainous regions differs from the foothills and plains. During the winter, a layer of snow accumulates up to 5 cm. On the northern slopes, the boundary of eternal ice begins.

At an altitude of 4000 m, even in the hottest summer, there are practically no positive temperatures. In winter, snow avalanches are possible from any sharp sound, unsuccessful movement.

Mountain rivers, stormy and cold, originate during the melting of snow and glaciers. That is why floods are so intense in spring and practically dry up in autumn when the temperature is low. Snowmelt stops in winter, and turbulent mountain streams become shallow.

The two most major rivers North Caucasus - Terek and Kuban - give the territory numerous tributaries. Thanks to them, fertile black earth soils are rich in crops.

Orchards, vineyards, tea plantations, berry fields smoothly pass into the arid zone. These are the features of the nature of the Caucasus. The cold of the mountains is replaced by the warmth of the plains and foothills, the black earth turns into chestnut soils.

Mineral water

You should know that the features of the North Caucasus are a whole complex of factors. These include the distance from the seas, oceans. The nature of the relief, landscape. Distance from equator and pole. Direction of air masses, abundance of precipitation.

It so happened that the nature of the Caucasus is diverse. There are fertile lands and arid regions. mountain meadows and pine forests. dry steppes and deep rivers. Wealth natural resources, the presence of mineral waters makes this area attractive for industry and tourism.

The description of the nature of the Caucasus is remarkable in that more than 70 healing springs can be found on its territory. These are cold, warm, hot mineral waters. They are different in composition, which helps in the prevention and treatment of diseases:

gastrointestinal tract;
skin;
circulatory systems;
nervous system.

The most famous hydrogen sulfide waters are located in the city of Sochi. Iron springs - in Zheleznovodsk. Hydrogen sulfide, radon - in Pyatigorsk. Carbon dioxide - in Kislovodsk, Essentuki.

Flora

The vegetation cover of the territory is as diverse as wildlife Russia. The Caucasus is divided into mountainous, foothill, plain zones. Depending on this, the vegetation cover of the region also changes. It is due to climatic conditions, soil, precipitation.

Mountain meadows - lush alpine, hayfields. Thickets of rhododendron add color to the herbs. There you can find juniper, a creeping shrub that is adapted to a snowy lifestyle. Broad-leaved forests rush to replace them, where oak, beech, chestnut, and hornbeam grow.

Meadow-marsh vegetation alternates with arid semi-desert areas. They are filled with artificial plantations - poppies, irises, tulips, groves of white acacia and oak.

Black-fruited lands are represented by extensive berry and vineyards. The nature of the Caucasus is favorable for fruit trees, shrubs - pears, cherry plums, hawthorn, blackthorn, dogwood.

Fauna

The steppes are inhabited by such animals as ground squirrel, jerboa, hare, steppe polecat, fox, wolf. The wild nature of Russia is also rich in them. The Caucasus, its semi-desert regions, are favorable for the eared hedgehog, comb and midday gerbil, earth hare and corsac fox. There are saigas (steppe antelopes). Roe deer live in the forests, Brown bear, bison

The nature of the Caucasus is distinguished by a large number of reptiles. Humid and warm climate is an excellent condition for their survival and reproduction. it steppe viper and boa constrictor, snake and lizards.

In you can find a wild boar, reed cat, jackals. There are waterfowl, as well as an eagle, a kite, a kestrel, a lark, a bustard, a harrier, a crane.

Minerals

The nature of the Caucasus is rich in large deposits of oil and gas. Deposits of black and brown coal, copper and manganese ores, asbestos, and rock salt are of industrial importance.

Soil studies have shown that everything necessary for National economy metals can be found in the North Caucasus. These are the deposits:

zinc;
copper;
chromium;
aluminum;
arsenic;
lead;
gland.

AT recent times the development of building stone gained wide popularity. Strong tuff lava and roofing slate are especially valued. For the construction of buildings, local Neogene limestone is used. The North Caucasus is famous for its deposits of granite, marble, basalt. Deposits of gold and silver have been discovered.

Conclusion

The main features of the nature of the North Caucasus lie in its diversity. A combination of glacial mountains with chokeberry lowlands, alpine meadows with semi-deserts. Abundant precipitation of the western territory passes into dry winds of the eastern regions.

Cyclones, warm and cold air fronts form a feature of the North Caucasus. Streams from the Atlantic Ocean and the Mediterranean Sea carry moisture. Dry air masses from Central Asia and Iran is doused with hot wind.

Clean, transparent air, saturated with ultraviolet light, gives longevity to its multinational inhabitants. warm, short winters, the high level of the agricultural sector attracts travelers. Healing springs, deposits of natural resources make this area tempting for the healthcare system and industry.

Multi-level landscape, numerous rivers - the natural beauty of the region is striking in its magnificence. Historical and cultural sights give an energy boost to this fertile area.

The Caucasus is one of southern regions Russia. Its extreme points lie within 50.5 ° N. sh. (northern extremity Rostov region) and from p. sh. (on the border of Dagestan). The territory of the North Caucasus receives a lot of solar radiation - approximately one and a half times more than, for example, the Moscow region. Its annual amount for the plains and foothill regions is 120-140 large calories (kilocalories) per square centimeter of surface.

In different seasons of the year, the radiation flux is different. In summer, each square centimeter of the surface receives 17-18 kcal per month. At this time, the heat balance is positive. In winter, the flow of sunlight is sharply reduced - up to 3-b kcal per 1 sq. km. cm per month and a lot of heat reflects the snow-covered earth's surface. Therefore, the radiation balance becomes negative for some time in the middle of winter.

In the North Caucasus, everywhere, with the exception of the highlands, there is a lot of heat. On the plains, the average temperatures in July everywhere exceed 20°, and summer lasts from 4.5 to 5.5 months. Average January temperatures fluctuate in different regions from -10° to +6°, and winter lasts only two or three months. The rest of the year is occupied by transitional seasons - spring and autumn.

Due to the abundance of heat and light, vegetation in the Caucasus has the opportunity to develop in the northern parts of the region for seven months, in Ciscaucasia - eight months, and on the Black Sea coast, south of Gelendzhik - up to 11 months. This means that with an appropriate selection of field and garden crops, one can get one and a half crops a year * in the north of the region, and even two crops in the entire Ciscaucasia.

The movement of air masses and their transformation in the territory of the North Caucasus are exceptionally complex and diverse. The area is located on the border of temperate and subtropical latitudes, not far from the warm Mediterranean Sea. As far north as the Arctic Ocean, there are no significant orographic obstacles. In the south, on the contrary, high chains of mountains rise. Therefore, in all seasons of the year, various air masses can penetrate into the North Caucasus: either the cold dry air of the Arctic, or the masses saturated with moisture formed above Atlantic Ocean, then the humid tropical air of the Mediterranean and, finally, although very rarely, also tropical, but dry and heavily dusty air from the desert highlands of Western Asia and the Middle East. Replacing each other, various air masses create a great diversity and variety of weather conditions, which distinguish the North Caucasus. But the main amount of precipitation is associated with westerly winds that carry moisture from the Atlantic. Their moisture is intercepted by the slopes of mountains and hills facing to the west, while to the east the dryness and continentality of the climate increases, which affects the entire landscape.

The nature of the circulation of air masses in different seasons of the year has noticeable differences. And, of course, the conditions of the plains and mountains are sharply different.

On the plains in winter, the cold dense air of Siberia and Kazakhstan (the Siberian, or Asian, anticyclone) collides with each other and the relatively warm rarefied air that sets over the Black Sea (the Black Sea depression). Under the influence of the Siberian anticyclone, streams of dry, strongly cooled air are constantly directed towards Ciscaucasia. Due to the significant difference in pressure, the air flows quickly, forming strong, often stormy easterly and northeasterly winds. These winds dominate throughout the winter in the Caspian region and in the eastern parts of Ciscaucasia. Due to the dryness of the air they bring, there is almost no precipitation here, and the thickness of the snow cover is small - 5-10 cm, in some places there is no snow at all.

Further to the west, the air of the Siberian anticyclone rarely penetrates. The entire Western Ciscaucasia is under the influence of the Black Sea depression: cyclones come from there, bringing sharp warming and a lot of precipitation. The snow cover in the west is 2-3 times thicker than in the east, the winter is unstable: frequent thaws sometimes last for a week or more, with temperatures rising to 6-12° in the north and up to 20° in the south of the region.

The Stavropol Upland is a kind of climatic boundary between the Eastern and Western Ciscaucasia. Here there are very heterogeneous in their physical properties air masses. In this case, the winds usually increase sharply; the variable wind regime is the main feature of winter in the Stavropol Territory.

Arctic air usually comes to the North Caucasus from the northwest. In the Lower Don and Ciscaucasia, this cold air, as a rule, is delayed for a long time by the dense air of the Siberian anticyclone and mountain ranges. Then, seemingly not at all characteristic of these southern places low temperatures. Thus, in Pyatigorsk and Maykop, the absolute minimums, that is, the lowest of the observed temperatures, are -30°, and in Krasnodar even -33°. The average lows are also quite severe: -16°, -20°.

The cold Arctic air, as if pressed against the ground, usually does not rise high and does not cross the mountain ranges that protect the Transcaucasus from the destructive northern cold. But cold invasions can bypass the Caucasus Mountains along their eastern margin along the Caspian coast, reaching Baku and its environs, often having a detrimental effect on the coastal regions of Dagestan along the way.

In the west, on a small section of the coast from Novorossiysk to Gelendzhik, where the mountain range is low, cold and dense air accumulating in the foothills sometimes rises to the saddle of the Markotkhsky pass. Then a bora falls on the city of Novorossiysk and the Tsemess Bay, in the local north-east - a wind of hurricane strength and speed, moreover, extremely cold. It often brings serious destruction to the urban economy and causes severe storms in the coastal parts of the sea.

In the spring, air masses heated from the earth's surface rush upwards and the pressure weakens. Then conditions are created for the active invasion of warm Mediterranean air. Under its influence, the unstable snow cover melts together, the average daily temperatures rise rapidly, and already in early May, summer conditions are established throughout the entire territory of the North Caucasus, except for the highlands.

In summer, the incoming air is actively transformed under the influence of a strongly heated earth's surface, and its own air, close to the tropical type, is formed on the territory of the region. On the plains everywhere, often for many weeks, an anticyclone sets in with its characteristic weather features: hot days prevail, with weak winds, low clouds and strong warming of the surface layers of air, almost without rain.

Only from time to time anticyclonic conditions are replaced by periods of passage of cyclones. They usually invade from the Atlantic through Western Europe, Belarus and Ukraine, and much less frequently from the Black Sea. Cyclones bring cloudy weather: On their leading fronts, showers fall, often accompanied by thunderstorms. Occasionally, long drizzling rains fall in the rear of passing cyclones.

Cyclones almost always come from the west or northwest, and as they move east and southeast, the air masses they bring lose their moisture reserves. Therefore, not only in winter, but also in summer, the western plain Ciscaucasia is more abundantly moistened than the eastern one. In the west, the annual precipitation is 380-520 mm, while in the Caspian region it is only 220-250 mm. True, in the foothills and on the Stavropol Upland, precipitation increases to 600-650 mm, but on the plains to the east of the upland, they are not enough to fully use the abundance in agriculture and horticulture. solar heat. The situation is further complicated by the extreme unevenness of precipitation over time.

In fact, the entire territory of the Lower Don and the plain Ciscaucasia is not guaranteed against the possibility of droughts with their constant companions - dry winds - a cruel, inexorable enemy of field and horticultural plants. However, not all areas are equally prone to these formidable natural phenomena. So, for the period from 1883 to 1946, that is, for 64 years, droughts occurred 21 times in the Caspian region, 15 times in the Rostov region, and only 5 times in the Kuban.

During droughts and dry winds, especially in the east, dusty or black storms often occur. They occur when the upper layers of dry soil, still loosely held together by newly emerged plants, are blown away. strong wind. A cloud of dust rises into the air, covering the sky with a thick veil. Sometimes the dusty cloud is so dense that the sun barely shines through it and appears as a hazy, blood-red disk.

Measures of protection against black storms are known. The main ones are properly planned forest shelterbelts and high agricultural technology. Much has already been done in this direction. However, until now, in the fields of Ciscaucasia, it is often necessary to re-sow (re-sow) several tens of thousands of hectares, from which during dust storms the most fertile layer of soil is being demolished.

In autumn, the influx of solar heat weakens. Initially, the features of the summer circulation are still preserved. Anticyclonic weather prevails with a weak movement of air masses. Subsequently, the earth's surface begins to noticeably cool, and from it the lower layers of air. In the mornings, thick milky-white fogs spread over the ground that has cooled overnight. The already strongly cooled air of the Siberian anticyclone comes more and more often, and in November a winter type of circulation is established over the entire territory of the North Caucasus.

The climate of the mountainous territories of the North Caucasus (from 800-900 m and above) is very different from the adjacent plains, although it repeats some of the most common features.

One of the main differences is that the mountain slopes, delaying the flow of air masses, make them rise up. At the same time, the temperature of the air mass decreases rapidly, and moisture saturation increases, which leads to precipitation. Therefore, the mountain slopes are much better moistened: in the mountains of the Western Caucasus at altitudes above 2000 m, 2500-2600 mm falls annually; to the east their number decreases to 900-1000 mm. The lower zone of the mountains - from 1000 to 2000 m - receives less precipitation, but still enough for the growth of lush forest vegetation.

Another difference is due to the decrease in temperature with increasing altitude: for every 100 m you rise, it drops by about 0.5-0.6°. In this regard, a belt distribution of climate is clearly manifested on the mountain slopes, and already at an altitude of 2700 m on the northern slopes of the mountains of the Western Caucasus, 3700-3800 m in the Central and 3500 m in the Eastern, there is a snow line, or the border of "eternal" snow. Above it, the warm season with positive temperatures lasts no more than 2.5-3 months, and at altitudes above 4000 m, even in July, positive temperatures are observed very rarely.

Due to the abundance of precipitation in the mountains of the Western Caucasus during the winter, 4–5 and snow accumulates, and in the mountain valleys, where it is blown away by the wind, up to 10–12 m. even a sharp sound, so that a thousand-ton mass of accumulated snow, breaking off a steep ledge, flew down with a terrible roar, destroying everything in its path. In the mountains of the Eastern Caucasus, due to the general dryness, the snow cover is much less.

The third difference between the mountain climate is that the chilled air of the highlands often, as it were, rushes down the comparatively narrow intermountain valleys. For every 100 m lowered, the air heats up by about 1°. Falling from a height of 2500 m, when it reaches the lower parts of the mountains and foothills, it heats up by 25 °, that is, instead of cold, it will become warm and even hot. Such winds are called foehns. They blow in all seasons, but especially often in the spring, when the intensity increases sharply. general circulation air masses.

Finally, another important distinguishing feature of the climate of the mountains is its amazing diversity from place to place, which is due to the rugged relief with numerous bends of the slopes, differently oriented with respect to the illumination of the sun and the directions of the prevailing winds. On the plains, differences in the orientation of the slopes are less pronounced due to their low steepness.

For all the importance of each of the noted features of the climate of the mountains, the height, which determines the vertical division into climatic zones, is still of leading importance.

2. Give a description of the climate of the Greater Caucasus, explain how the climate of the foothills differs from high mountain areas?

The climate of the Greater Caucasus is determined by its southern location, the proximity of the Black and Mediterranean Seas, as well as the significant height of the mountain ranges. The Greater Caucasus is a barrier to the movement of masses of humid warm air from the west. More precipitation falls on the southern slopes, the maximum amount is in the western part, where more than 2500 mm per year falls in the highlands (most of all in our country). To the east, precipitation drops to 600 mm per year. The northern slope of the Greater Caucasus is generally drier than the southern one.
In the mountains of the Greater Caucasus, in a relatively small area, there is a wide range of climatic zones with pronounced zonality in height: humid subtropics of the Black Sea coast continental dry (in the east to semi-desert) climate with hot summers and short, but cold winter on the plains of Ciscaucasia moderately continental climate foothills with significant precipitation (especially in the western part) and snowy winters (in the Krasnaya Polyana area, on the watershed of the Bzyb and Chkhalta rivers, the snow cover reaches 5 m and even 8 m). In the zone of alpine meadows, the climate is cold and humid, winter lasts up to 7 months, the average temperatures of August - the warmest month - range from 0 to + 10C. Above is the so-called nival belt, where the average temperature of even the warmest month does not exceed 0. Precipitation here falls mainly in the form of snow or grains (hail).

The average January temperatures at the foot of the mountains are -5С in the north and from +3 to +6С in the south at an altitude of 2000 m -7-8С, at an altitude of 3000 m -12С, at an altitude of 4000 m -17С. The average temperature in July at the foot of the mountains in the west is +24С, in the east up to +29С at an altitude of 2000 m +14С, at an altitude of 3000 m +8С, at an altitude of 4000 m +2С.

In the Greater Caucasus, the height of the snow line, rising from west to east, fluctuates between 2700 m - 3900 m above sea level. Its northern mark is different for the northern and southern slopes. In the Western Caucasus, these are 3010 and 2090 m, respectively, in the Central - 3360 and 3560 m, in the Eastern - 3700 and 3800 m. The total area of modern glaciation of the Greater Caucasus is 1780 km. The number of glaciers is 2047, their tongues descend to absolute levels: 2300-2700 m ( Western Caucasus) , 1950-2400 m (Central Caucasus), 2400-3200 m (Eastern Caucasus). Most of glaciation falls on the north side of the GKH. The distribution of the glaciation area is as follows: Western Caucasus - 282 and 163 sq. km Central Caucasus - 835 and 385 sq. km East Caucasus - 114 and 1 sq. km, respectively.
Caucasian glaciers are distinguished by a variety of forms. Here you can see grandiose icefalls with seracs, ice grottoes, "tables", "mills", deep cracks. Glaciers carry out a large amount of detrital material that accumulates in the form of various moraines on the sides and at the tongue of the glaciers.

The climatic region of the natural region of the Caucasus is different: Ciscaucasia occupies a temperate climate region, and Transcaucasia is subtropical. climatic regions different, because different terrain, air currents, local circulation. Changes in climatic conditions in the Caucasus occur in three directions. From the western part of the Caucasus towards the east, the continentality of the climate increases. The total solar radiation increases from north to south. The higher the mountains, the lower the temperature and the more precipitation. In the North Caucasus, solar radiation is 1.5 times more than in the Moscow region, per 1 cm2 per year. surface 120-140 kC. Depending on the season, the radiation flux is different: in summer the heat balance is positive, and in winter it is negative, since a certain percentage of radiation is reflected by the snow cover. Summer is long. The fluctuation of temperatures in July on the plains is more than +20 degrees. In January, the temperature ranges from -10 to +6 degrees Celsius.

In the north of the Caucasus, the continental air of temperate latitudes dominates. Transcaucasia is a zone of subtropical air masses. The north is devoid of orographic obstacles, and the south has high mountains, so during the year various air masses penetrate here - cold Arctic air, humid air of the Mediterranean tropics, Atlantic humid air masses or dry and dusty Asiatic and Middle Eastern air. In the Ciscaucasia, winter is dominated mainly by continental air from temperate latitudes. AT winter time areas are formed over the Black and Caspian Seas low pressure, so there are strong cold winds. The Asian anticyclone is moving to the east, which reduces the amount of snow. AT winter period a local anticyclone is forming over the Armenian Highlands. In the Ciscaucasia, the temperature drops to 30-36 with a minus mark due to the cold northern air. The minimum temperature in Anapa is 260C, in Sochi - 150C.

In the cold season, the influence of cyclones on the Black Sea coast increases, so the amount of precipitation during this period is the largest. In the rest of the territory, the maximum precipitation is observed in summer period. In winter, snow falls in the mountains of the Caucasus and on the plains. There are snowless winters. The thickness of the snow cover on the plains is from 10 to 15 cm. The southwestern slopes of the Greater Caucasus are covered with a 3-4 meter snow blanket. The summer climate of the Caucasus is formed mainly by humid air from the Atlantic and dry continental air. The air temperature of the Western Ciscaucasia and the Black Sea coast reaches + 22, +23 degrees, the eastern Ciscaucasia reaches +24, + 25 degrees. There is a noticeable drop in temperature with height. On Elbrus, the average thermometer is only +1.4 degrees.

In Ciscaucasia, Atlantic cyclones bring the maximum amount of precipitation in the first half of summer. In the middle of summer, air masses transform over the southeast of the East European Plain, which leads to a decrease in precipitation and the formation of dry winds with droughts. Rising from the foothills to the mountains, the amount of precipitation increases, but in the eastern part it decreases significantly. The annual indicator of the Kuban-Azov lowland reaches 550-600 mm of precipitation. If we consider the Sochi region, then the figure will be equal to 1650 mm. In the west of the mountains of the Greater Caucasus, on average, 2000 - 3000 mm of precipitation falls, and in eastern region the indicator is 1000-1500 mm. The greatest amount of precipitation was recorded on the windward slopes of the Greater Caucasus from southwest side. For example, at the Achishkho station, the largest amount of precipitation falls not only in the Caucasus region, but also in all of Russia taken together. This figure reaches more than 3700 mm per year.

The modern glaciation of the Caucasus is associated with its climate and relief features. There are 1498 glaciers in the Russian Caucasus, which is 70% of the total number of glaciers, as well as the glaciation area of the Greater Caucasus.

Rivers of the Caucasus

The mountains of the Caucasus collect a large amount of moisture. These are rains, snow, glaciers. It is in the mountains that the sources of all Caucasian rivers are located. Through the flat territories of Ciscaucasia, the waters of the rivers fall into the Black, Azov and Caspian Sea. Mostly mountain rivers with a rapid current. There are also lowland rivers in the Caucasus, which have a slow flow and a small flood. The Stavropol Upland is the starting point for part of the lowland rivers. In summer, they dry up, forming a kind of chain of lakes. The upper reaches of the rivers Kuban, Kuma, Rioni, Terek, Kura, Araks are located in the mountains, and the lower reaches are on the plains. These rivers are fed by rain and groundwater. Downpours feed the rivers located between Tuapse and Sochi, turning them into swift streams. When there is no rain, rivers turn into streams. The sources of the mountain rivers Bzyb, Kodor, Inguri are located at an altitude of 2 to 3 thousand meters. Sulak and Terek flow at high speed through deep canyon-like gorges. These rivers have rapids and waterfalls.

The density of the river network of valleys is uneven and reaches only 0.05 km/sq. km. The southern slope of the mountain system has a dense river network. The rivers of the Caucasus, especially in Dagestan, are muddy, as rocks are washed out, as well as various sediments. Most muddy waters the rivers Kura and Terek. The Kuban, Kagalnik, Western Manych, Chelbas and Beisug flow into the Black Sea. The rivers of the Caspian Sea basin are Samur, Terek, Sulak, East Manych, Kuma and Kalaus.

The Caucasian rivers have an insignificant transport function. The Kura, Rioni, Kuban can be attributed to the category of navigable. They use rivers for the purpose of irrigating territories, and it is also convenient to float timber along them. There are hydroelectric power stations on many Caucasian rivers.

Lakes of the Caucasus

There are few lakes in the Caucasus. The total number is about 2 thousand. The area of lakes is small. An exception can be considered the mountain lake Sevan, the height of the water surface of which is 1916 m, and the greatest depth is 99 m. The area and depth of the lake have slightly decreased due to the construction of a hydroelectric power station on it. This factor affected not only the lake, but also the nature of the adjacent territory. Some species of animals have disappeared, the number of fish has decreased, and bare peat bogs have formed on the ground.

The plains of the coasts of the Azov and Caspian Seas contain lagoonal and estuary lakes. Manych lakes formed a whole system. Certain lakes in this system sometimes dry up during the summer.

The foothills and lower slopes of lakes do not have, but there are many of them in the mountains. The basins of mountain lakes are different in origin. Most of them are tectonic, but there are also karst, volcanic and cirque. Lakes of volcanic origin are marked by damming. River basin Teberdy is famous for its lakes of glacial origin that have survived to this day. The floodplains of flat rivers are decorated with original lakes. For example, such is the dammed lake Ritsa, located in the mountains.