Types of climate zones. Climate zones of the planet - a brief educational program. Deciduous and mixed forests

- Types of climates (climatic zones) of Russia.

General characteristics of the Earth's climate zones.

Climate zones differ from each other:

• degree of heating by the sun;
• peculiarities of atmospheric circulation;
• seasonal changes in air masses.

Climatic zones differ significantly from each other, gradually changing from the equator to the poles. However, climate is influenced not only by the latitude of the Earth, but also by the terrain, proximity to the sea, and altitude.

In Russia and in most countries of the world, the classification of climate zones created by the famous Soviet climatologist is used B.P. Alisov in 1956.

According to this classification, there are four main climatic zones on the globe and three transitional ones - with the prefix “sub” (Latin “under”):

• Equatorial (1 belt);
• Subequatorial (2 zones - in the northern and southern hemispheres);
• Tropical (2 zones - in the northern and southern hemispheres);
• Subtropical (2 zones - in the northern and southern hemispheres);
• Moderate (2 zones - in the northern and southern hemispheres);
• Subpolar (2 zones - subantarctic in the south, subarctic in the north);
• Polar (2 zones - Antarctic in the south, Arctic in the north);

Within these climatic zones, four types of Earth's climate are distinguished:

• Continental,
• Oceanic,
• The climate of the western shores,
• Climate of the eastern shores.

Let us consider in more detail the climate zones of the Earth and the types of climates inherent in them.

Climatic zones and types of climates of the Earth:

1. Equatorial climate zone– the air temperature in this climate zone is constant (+24-28°C). At sea, temperature fluctuations can generally be less than 1°. The annual amount of precipitation is significant (up to 3000 mm); on the windward slopes of the mountains, precipitation can fall up to 6000 mm.

2. Subequatorial climate– is located between the equatorial and tropical main types of Earth’s climate. In summer, this zone is dominated by equatorial air masses, and in winter - tropical. The amount of precipitation in summer is 1000-3000 mm. Average summer temperature+30°С. In winter there is little precipitation, the average temperature is +14°C.

Subequatorial and equatorial belts. From left to right: savannah (Tanzania), rainforest (South America)

3. Tropical climate zone. In this type of climate, a distinction is made between continental tropical climate and oceanic tropical climate.

• mainland tropical climate – annual precipitation - 100-250 mm. The average summer temperature is +35-40°C, winter +10-15°C. Daily temperature fluctuations can reach 40 °C.
• oceanic tropical climate - annual precipitation – up to 50 mm. The average summer temperature is +20-27°C, winter +10-15°C.

Tropical zones of the Earth. From left to right: deciduous forest(Costa Rica), veld ( South Africa), desert (Namibia).

4. Subtropical climate– is located between the tropical and temperate main types of Earth’s climate. In summer, tropical air masses dominate, and in winter, air masses of temperate latitudes invade here, carrying precipitation. The subtropical climate is characterized by hot, dry summers (from +30 to +50°C) and relatively Cold winter with precipitation, no stable snow cover is formed. Annual precipitation is about 500 mm.

• dry subtropical climate - observed inside continents in subtropical latitudes. Summer is hot (up to +50°C) and in winter frosts down to -20°C are possible. Annual precipitation is 120 mm or less.
• Mediterranean climate – observed in the western parts of the continents. Summer is hot, without precipitation. Winter is cool and rainy. The annual precipitation is 450-600 mm.
• subtropical climate of the eastern coasts continents is monsoon. Winter, compared to other climates of the subtropical zone, is cold and dry, and summer is hot (+25°C) and humid (800 mm).

Subtropical zones of the Earth. From left to right: evergreen forest(Abkhazia), prairie (Nebraska), desert (Karakum).

5. Temperate climate zone. It is formed over areas of temperate latitudes - from 40-45° northern and southern latitudes to the polar circles. Annual precipitation ranges from 1000 mm to 3000 mm on the outskirts of the continent and up to 100 mm in the interior. Temperatures in summer range from +10°C to +25-28°C. In winter - from +4°С to -50°С. In this type of climate, a distinction is made between marine, continental and monsoon climates.

• nautical temperate climate – annual precipitation - from 500 mm to 1000 mm, in the mountains up to 6000 mm. Summers are cool +15-20°C, winters are warm from +5°C.
• continental temperate climate – annual precipitation is about 400 mm. Summers are warm (+17-26°C), and winters are cold (-10-24°C) with stable snow cover for many months.
• monsoon temperate climate - annual precipitation is about 560 mm. Winter is clear and cold (-20-27°C), summer is humid and rainy (-20-23°C).

Natural zones of the Earth's temperate zones. From left to right: taiga (Sayan Mountains), deciduous forest ( Krasnoyarsk region), steppe (Stavropol region), desert (Gobi).

6. Subpolar climate- consists of subarctic and subantarctic climatic zones. In summer, humid air masses come here from temperate latitudes, so summers are cool (from +5 to +10°C) and about 300 mm of precipitation falls (in the northeast of Yakutia 100 mm). In winter, the weather in this climate is influenced by Arctic and Antarctic air masses, so there are long, cold winters, temperatures can reach -50°C.
7. Polar climate type - Arctic and Antarctic climate zones. Forms above 70° north and below 65° south latitudes. The air is very cool, the snow cover does not melt all year. There is very little precipitation, the air is saturated with small ice needles. As they settle, they provide a total of only 100 mm of precipitation per year. The average summer temperature is not higher than 0°C, winter - -20-40°C.

Subpolar climate zones of the Earth. From left to right: arctic desert(Greenland), tundra (Yakutia), forest-tundra (Khibiny).

The characteristics of the Earth's climates are presented more clearly in the table.

Characteristics of the Earth's climatic zones. Table.

Note: Dear visitors, hyphens in long words in the table are placed for the convenience of mobile users - otherwise the words will not be transferred and the table will not fit on the screen. Thanks for understanding!

Types of climates (climatic zones) of Russia:

• Arctic: January t −24…-30, summer t +2…+5. Precipitation - 200-300 mm.
• Subarctic: (up to 60 degrees N). summer t +4…+12. Precipitation is 200-400 mm.
• Moderate continental: January t −4…-20, July t +12…+24. Precipitation 500-800 mm.
• Continental climate: January t −15…-25, July t +15…+26. Precipitation 200-600 mm.

Very varied. The first climate classifications appeared in the 70s of the 19th century and were of a descriptive nature. According to the classification of Moscow State University professor B.P. Alisov, there are 7 types of climates on Earth, which make up climatic zones. 4 of them are basic, and 3 are transitional. The main types include:

Equatorial climate zone. This type of climate is characterized by the dominance of equatorial climates throughout the year. On the days of the spring (March 21) and autumn (September 21) equinox, the Sun is at its zenith above the equator and greatly heats the Earth. The air temperature in this climate zone is constant (+24-28°C). At sea, temperature fluctuations can generally be less than 1°. The annual amount of precipitation is significant (up to 3000 mm); on the windward slopes of the mountains, precipitation can fall up to 6000 mm. The amount of precipitation here exceeds evaporation, so in the equatorial climate they are swampy, and dense and tall trees grow on them. The climate of this zone is also influenced by the trade winds, which bring an abundance of precipitation here. The equatorial climate type is formed over the northern regions; on the coast of the Gulf of Guinea, over the basin and headwaters, including the shores of Lake Victoria in Africa; over most of the Indonesian archipelago and adjacent parts and the Pacific Oceans in Asia.
Tropical climate zone. This type of climate forms two tropical climate zones (in the Northern and Southern Hemisphere) over the following areas.

In this type of climate, the state of the atmosphere over the continent and the ocean is different, therefore a continental tropical climate and an oceanic tropical climate are distinguished.

Continental climate zone: the region dominates over a significant territory, so very little precipitation falls here (from 100-250 mm). The mainland tropical climate is characterized by very hot summers (+35-40°C). In winter, the temperature is much lower (+10-15°C). There are large daily temperature fluctuations (up to 40 °C). The absence of clouds in the sky leads to the formation of clear and cold nights (clouds could trap heat coming from the Earth). Sharp daily and seasonal temperature changes contribute, which produces a lot of sand and dust. They are picked up by winds and can be transported over considerable distances. These are dusty sandstorms are a great danger for a traveler in.

Mainland tropical climates The western and eastern coasts of the continents are very different from each other. Cold currents pass along the western coasts of South America and Africa, so the climate here is characterized by relatively low air temperatures (+18-20°C) and low precipitation (less than 100 mm). Warm currents pass along the eastern coasts of these continents, so temperatures here are higher and there is more precipitation.

Oceanic tropical climate similar to the equatorial one, but differs from it in smaller and more stable winds. Summer over the oceans is not so hot (+20-27°C), and winter is cool (+10-15°C). Precipitation falls mainly in summer (up to 50 mm). Moderate. There is a significant impact western winds, bringing precipitation all year round. Summer in this climate zone is moderately warm (from +10°C to +25-28°C). Winter is cold (from +4°С to -50°С). Annual precipitation ranges from 1000 mm to 3000 mm on the outskirts of the continent and up to 100 mm in the interior. The differences between the seasons of the year are clearly visible. This type of climate also forms two zones in the Northern and Southern Hemispheres and is formed over areas of temperate latitudes (from 40-45° northern and southern latitudes to the polar circles). A region is formed above these territories low pressure, active cyclonic activity. Temperate climates are divided into two subtypes:

1. nautical, which dominates the western parts North America, South America, is formed under the direct influence of westerly winds from the ocean to the mainland, therefore it has cool summers (+15-20°C) and warm winters (from +5°C). Precipitation brought by westerly winds falls all year round(from 500 mm to 1000 mm, in the mountains up to 6000 mm);
2. continental, dominant in central regions continents, differs from it. Cyclones penetrate here less frequently than in coastal areas, so summers here are warm (+17-26°C), and winters are cold (-10-24°C) with stable snow cover for many months. Due to the significant extent of Eurasia from west to east, the most pronounced continental climate is observed in Yakutia, where average January temperatures can drop to -40°C and there is little precipitation. This happens because the interior of the continent is not exposed to the same influence of the oceans as the coasts, where moist winds not only bring precipitation, but also mitigate the heat in summer and frost in winter.

The monsoon subtype of temperate climate, dominant in the east of Eurasia to Korea and in the north, northeast, is characterized by a change in stable winds (monsoons) over the seasons, which affects the amount and regime of precipitation. It blows here in winter cold wind from the continent, so winter is clear and cold (-20-27°C). In summer, winds bring warm, rainy weather. In Kamchatka, precipitation falls from 1600 to 2000 mm.

In all subtypes of temperate climates, only moderate air masses dominate.

Polar climate type. Above 70° north and 65° south latitudes, a polar climate prevails, forming two zones: and. Polar air masses prevail here all year round. The sun does not appear at all for several months (polar night) and does not go below the horizon for several months (polar day). Snow and ice emit more heat than they receive, so the air is very cool and does not melt all year round. Throughout the year, these territories are dominated by the region high pressure, so the winds are weak and there are almost no clouds. There is very little precipitation, the air is saturated with small ice needles. As they settle, they provide a total of only 100 mm of precipitation per year. The average summer temperature does not exceed 0°C, and winter -20-40°C. Long drizzle is typical for summer.

Equatorial, tropical, temperate, polar climate types are considered the main ones, since within their zones the air masses characteristic of them dominate throughout the year. Between the main climatic zones there are transitional ones, which have the prefix “sub” (Latin for “under”) in their names. In transitional climate zones, air masses change seasonally. They come here from neighboring belts. This is explained by the fact that as a result of the movement of the Earth around its axis, climatic zones shift either to the north or to the south.

There are three additional type climate:

Subequatorial climate. In summer, this belt is dominated by equatorial air masses, and in winter by tropical ones.

Summer: a lot of precipitation (1000-3000 mm), average +30°C. Even in the spring the sun reaches its zenith and burns mercilessly.

Winter is cooler than summer (+14°C). There is little precipitation. Soils after summer rains dry out, so in the subequatorial climate, unlike the equatorial climate, swamps are rarely found. The territory is favorable for human settlement, which is why many centers of civilization are located here - Indochina. According to N.I. , it is from here that many varieties of cultivated plants originated. The northern subequatorial belt includes: South America (Isthmus of Panama); Africa (Sahel belt); Asia (India, all of Indochina, Southern China, ). The southern subequatorial belt includes: South America (Amazonian lowland); Africa (centre and east of the continent); (northern coast of the mainland).

Subtropical climate. Here in summer tropical air masses dominate, and in winter air masses of temperate latitudes invade here, carrying precipitation. This determines the following weather in these areas: hot, dry summers (from +30 to +50°C) and relatively cold winters with precipitation, no stable snow cover is formed. Annual precipitation is about 500 mm. Inside the continents in subtropical latitudes there is little precipitation even in winter. The climate here is dominated by dry subtropics with hot summers (up to +50°C) and unstable winters, when frosts down to -20°C are possible. Precipitation in these areas is 120 mm or less. In the western parts of the continents it dominates, which is characterized by hot, partly cloudy summers without precipitation and cool, windy and rainy winters. The Mediterranean climate receives more precipitation than the dry subtropics. The annual precipitation here is 450-600 mm. The Mediterranean climate is extremely favorable for human life, which is why the most famous summer resorts are located here. Valuable subtropical crops are grown here: citrus fruits, grapes, olives.

The subtropical climate of the eastern coasts of the continents is monsoon. Winter here, compared to other climates of the subtropical zone, is cold and dry, and summer is hot (+25°C) and humid (800 mm). This is explained by the influence of the monsoons, which blow from land to sea in winter, and from sea to land in summer, bringing precipitation in summer. The monsoon subtropical climate is well defined only in the Northern Hemisphere, especially on the east coast of Asia. Heavy rainfall in summer time give the opportunity to develop magnificently. On fertile soils It is developed here, supporting the lives of more than a billion people.

Subpolar climate. In summer, humid air masses come here from temperate latitudes, so summers are cool (from +5 to +10°C) and about 300 mm of precipitation falls (in the northeast of Yakutia 100 mm). As elsewhere, precipitation increases on windward slopes. Despite not a large number of precipitation, the moisture does not have time to evaporate completely, therefore, in the north of Eurasia and North America, small lakes are scattered in the subpolar zone, and large areas are swampy. In winter, the weather in this climate is influenced by Arctic and Antarctic air masses, so there are long, cold winters, temperatures can reach -50°C. Subpolar climate zones are located only on the northern edges of Eurasia and North America and in the Antarctic waters.

Climate- This is a long-term weather regime characteristic of a particular area. It manifests itself in the regular change of all types of weather observed in this area.

Climate influences living and inanimate nature. Are closely dependent on climate water bodies, soil, vegetation, animals. Certain sectors of the economy, primarily Agriculture, are also very dependent on climate.

Climate is formed as a result of the interaction of many factors: quantity solar radiation, arriving at the earth's surface; atmospheric circulation; the nature of the underlying surface. At the same time, climate-forming factors themselves depend on geographical conditions of this area, primarily from geographical latitude.

The geographic latitude of the area determines the angle of incidence of the sun's rays, obtaining a certain amount of heat. However, receiving heat from the Sun also depends on proximity to the ocean. In places far from the oceans, there is little precipitation, and the precipitation regime is uneven (more in the warm period than in the cold), cloudiness is low, winters are cold, summers are warm, and the annual temperature range is large. This climate is called continental, as it is typical for places located in the interior of continents. A maritime climate is formed over the water surface, which is characterized by: a smooth variation in air temperature, with small daily and annual temperature amplitudes, large clouds, and a uniform and fairly large amount of precipitation.

The climate is also greatly influenced by sea ​​currents. Warm currents warm the atmosphere in the areas where they flow. For example, the warm North Atlantic Current creates favorable conditions for the growth of forests in the southern part of the Scandinavian Peninsula, while most of the island of Greenland, which lies at approximately the same latitudes as the Scandinavian Peninsula, but is outside the zone of influence warm current, is covered with a thick layer of ice all year round.

A major role in climate formation belongs to relief. You already know that with every kilometer the terrain rises, the air temperature drops by 5-6 °C. Therefore, on the high mountain slopes of the Pamirs the average annual temperature- 1 °C, although it is located just north of the tropics.

The location of mountain ranges greatly influences the climate. For example, Caucasus Mountains They trap moist sea winds, and on their windward slopes facing the Black Sea, much more precipitation falls than on the leeward ones. At the same time, the mountains serve as an obstacle to cold northern winds.

There is a dependence of climate on prevailing winds. On the territory of the East European Plain, for almost the entire year, they are dominated by westerly winds coming from Atlantic Ocean Therefore, winters in this area are relatively mild.

Regions of the Far East are under the influence of monsoons. In winter, winds from the interior of the mainland constantly blow here. They are cold and very dry, so there is little precipitation. In summer, on the contrary, winds bring a lot of moisture from the Pacific Ocean. In autumn, when the wind from the ocean subsides, the weather is usually sunny and calm. This best time years in this area.

Climatic characteristics are statistical inferences from long-term weather observation series (in temperate latitudes 25-50-year series are used; in the tropics their duration may be shorter), primarily on the following basic meteorological elements: atmospheric pressure, wind speed and direction, temperature and air humidity, cloudiness and precipitation. The duration of solar radiation, visibility range, and temperature are also taken into account. upper layers soil and water bodies, evaporation of water from earth's surface into the atmosphere, the height and condition of the snow cover, various atmospheric phenomena and ground hydrometeors (dew, ice, fog, thunderstorms, snowstorms, etc.). In the 20th century in number climate indicators included the characteristics of the elements of the heat balance of the earth's surface, such as total solar radiation, radiation balance, the amount of heat exchange between the earth's surface and the atmosphere, and heat consumption for evaporation. Complex indicators are also used, i.e. functions of several elements: various coefficients, factors, indices (for example, continentality, aridity, moisture), etc.

Climate zones

Long-term average values ​​of meteorological elements (annual, seasonal, monthly, daily, etc.), their sums, frequency, etc. are called climate standards: corresponding values ​​for individual days, months, years, etc. are considered as a deviation from these norms.

Maps with climate indicators are called climatic(temperature distribution map, pressure distribution map, etc.).

Depending on temperature conditions, prevailing air masses and winds, climatic zones.

The main climatic zones are:

• equatorial;
• two tropical;
• two moderate;
• Arctic and Antarctic.

Between the main zones there are transitional climatic zones: subequatorial, subtropical, subarctic, subantarctic. In transitional zones, air masses change seasonally. They come here from neighboring zones, so the climate of the subequatorial zone in summer is similar to the climate of the equatorial zone, and in winter - to the tropical climate; The climate of the subtropical zones in summer is similar to the climate of the tropical zones, and in winter - to the climate of the temperate zones. This is due to the seasonal movement of atmospheric pressure belts over the globe following the Sun: in summer - to the north, in winter - to the south.

Climatic zones are divided into climatic regions. So, for example, in tropical zone Africa is divided into areas of tropical dry and tropical humid climates, and in Eurasia the subtropical zone is divided into areas of Mediterranean, continental and monsoon climates. In mountainous areas it is formed altitudinal zone due to the fact that the air temperature decreases with altitude.

Diversity of Earth's climates

The climate classification provides an orderly system for characterizing climate types, their zoning and mapping. Let us give examples of climate types that prevail over vast territories (Table 1).

Arctic and Antarctic climate zones

Antarctic and Arctic climate dominates in Greenland and Antarctica, where average monthly temperatures are below O °C. Into the dark winter time During the year, these regions receive absolutely no solar radiation, although there are twilights and auroras. Even in summer, the sun's rays hit the earth's surface at a slight angle, which reduces the efficiency of heating. Most of the incoming solar radiation is reflected by the ice. In both summer and winter, the higher elevations of the Antarctic Ice Sheet experience low temperatures. The climate of the interior of Antarctica is much colder than the climate of the Arctic, because southern mainland It is distinguished by its large size and altitude, and the Arctic Ocean moderates the climate, despite the widespread distribution of pack ice. During short periods of warming in summer, drifting ice sometimes melts. Precipitation on ice sheets falls in the form of snow or small particles of freezing fog. Inland areas receive only 50-125 mm of precipitation annually, but the coast can receive more than 500 mm. Sometimes cyclones bring clouds and snow to these areas. Snowfalls are often accompanied by strong winds that carry significant masses of snow, blowing it off the slope. Strong katabatic winds with snowstorms blow from the cold glacial sheet, carrying snow to the coast.

Subarctic continental climate is formed in the north of the continents (see. climate map atlas). In winter, arctic air predominates here, which forms in areas of high pressure. Arctic air spreads to the eastern regions of Canada from the Arctic.

Continental subarctic climate in Asia is characterized by the largest annual amplitude of air temperature on the globe (60-65 °C). The continental climate here reaches its maximum value.

The average temperature in January varies across the territory from -28 to -50 °C, and in the lowlands and basins due to stagnation of air, its temperature is even lower. In Oymyakon (Yakutia), a record negative air temperature for the Northern Hemisphere was recorded (-71 °C). The air is very dry.

Summer in subarctic zone although short, it is quite warm. Average monthly temperature in July it ranges from 12 to 18 °C (daytime maximum - 20-25 °C). During the summer, more than half of the annual precipitation falls, amounting to 200-300 mm on the flat territory, and up to 500 mm per year on the windward slopes of the hills.

The climate of the subarctic zone of North America is less continental compared to the corresponding climate of Asia. There are less cold winters and colder summers.

Temperate climate zone

Temperate climate of the western coasts of the continents has pronounced features of a marine climate and is characterized by the predominance of marine air masses throughout the year. It is observed on Atlantic coast Europe and the Pacific coast of North America. The Cordillera is a natural boundary separating the coast with a maritime climate from inland areas. The European coast, except Scandinavia, is open to free access of temperate sea air.

Permanent transfer sea ​​air is accompanied by heavy cloudiness and causes long springs, in contrast to the interior of the continental regions of Eurasia.

Winter in temperate zone It's warm on the western coasts. The warming influence of the oceans is enhanced by warm sea currents washing the western shores of the continents. The average temperature in January is positive and varies across the territory from north to south from 0 to 6 °C. When arctic air invades, it can drop (on the Scandinavian coast to -25 °C, and on the French coast - to -17 °C). As tropical air spreads northward, the temperature rises sharply (for example, it often reaches 10 °C). In winter, on the western coast of Scandinavia, large positive temperature deviations from the average latitude (by 20 °C) are observed. The temperature anomaly on the Pacific coast of North America is smaller and amounts to no more than 12 °C.

Summer is rarely hot. The average temperature in July is 15-16 °C.

Even during the day, the air temperature rarely exceeds 30 °C. Due to frequent cyclones, all seasons are characterized by cloudy and rainy weather. There are especially many cloudy days on the west coast of North America, where cyclones are forced to slow down their movement in front of the Cordillera mountain systems. In connection with this, great uniformity characterizes the weather regime in southern Alaska, where there are no seasons in our understanding. Eternal autumn reigns there, and only plants remind of the onset of winter or summer. Annual precipitation ranges from 600 to 1000 mm, and on the slopes of mountain ranges - from 2000 to 6000 mm.

In conditions of sufficient moisture on the coasts, developed broadleaf forests, and in conditions of excess - conifers. Lack of summer heat reduces upper limit forests in the mountains up to 500-700 m above sea level.

Temperate climate of the eastern coasts of the continents has monsoon features and is accompanied by a seasonal change in winds: in winter, northwestern currents predominate, in summer - southeastern ones. It is well expressed on the eastern coast of Eurasia.

In winter, with the north-west wind, cold continental temperate air spreads to the coast of the mainland, which is the reason for the low average temperature of the winter months (from -20 to -25 ° C). Clear, dry, windy weather prevails. There is little precipitation in the southern coastal areas. The north of the Amur region, Sakhalin and Kamchatka often fall under the influence of cyclones moving over Pacific Ocean. Therefore, in winter there is a heavy snow cover, especially in Kamchatka, where it maximum height reaches 2 m.

In summer, temperate sea air spreads along the Eurasian coast with a southeast wind. Summers are warm, with an average July temperature of 14 to 18 °C. Frequent precipitation is caused by cyclonic activity. Their annual quantity is 600-1000 mm, with most of them falling in summer. Fogs are common at this time of year.

Unlike Eurasia, the east coast of North America is characterized by monkfish climate, which are expressed in the predominance of winter precipitation and marine type annual progress air temperatures: the minimum occurs in February, and the maximum in August, when the ocean is warmest.

The Canadian anticyclone, unlike the Asian one, is unstable. It forms far from the coast and is often interrupted by cyclones. Winter here is mild, snowy, wet and windy. In snowy winters, the height of the snowdrifts reaches 2.5 m. With a southerly wind, there is often black ice. Therefore, some streets in some cities in eastern Canada have iron railings for pedestrians. Summer is cool and rainy. Annual precipitation is 1000 mm.

Temperate continental climate most clearly expressed on the Eurasian continent, especially in the regions of Siberia, Transbaikalia, northern Mongolia, as well as in the Great Plains in North America.

Feature of moderate continental climate is the large annual amplitude of air temperature, which can reach 50-60 °C. IN winter months With a negative radiation balance, the earth's surface cools. The cooling effect of the land surface on the surface layers of air is especially great in Asia, where in winter a powerful Asian anticyclone forms and partly cloudy, windless weather prevails. Moderate continental air forming in the area of ​​the anticyclone has low temperature(-0°...-40 °С). In valleys and basins, due to radiation cooling, the air temperature can drop to -60 °C.

In the middle of winter the continental air lower layers It's getting even colder than the Arctic. This very cold air of the Asian anticyclone extends to Western Siberia, Kazakhstan, and the southeastern regions of Europe.

The winter Canadian anticyclone is less stable than the Asian anticyclone due to the smaller size of the North American continent. Winters here are less severe, and their severity does not increase towards the center of the continent, as in Asia, but, on the contrary, decreases somewhat due to the frequent passage of cyclones. Continental temperate air in North America has a higher temperature than continental temperate air in Asia.

The formation of a continental temperate climate is significantly influenced by the geographical features of the continents. In North America, the Cordillera mountain ranges are a natural boundary separating the maritime coastline from the continental inland areas. In Eurasia, a temperate continental climate is formed over a vast expanse of land, from approximately 20 to 120° E. d. Unlike North America, Europe is open to the free penetration of sea air from the Atlantic deep into its interior. This is facilitated not only by the westerly transport of air masses, which dominates in temperate latitudes, but also by the flat nature of the relief, highly rugged coastlines and deep penetration of the Baltic and North Seas into the land. Therefore, a temperate climate is forming over Europe to a lesser extent continentality compared to Asia.

In winter, sea Atlantic air moving over the cold land surface of temperate latitudes of Europe retains its properties for a long time. physical properties, and its influence extends throughout Europe. In winter, as the Atlantic influence weakens, the air temperature decreases from west to east. In Berlin it is 0 °C in January, in Warsaw -3 °C, in Moscow -11 °C. In this case, the isotherms over Europe have a meridional orientation.

The fact that Eurasia and North America face the Arctic basin as a broad front contributes to the deep penetration of cold air masses onto the continents throughout the year. Intense meridional transport of air masses is especially characteristic of North America, where arctic and tropical air often replace each other.

Tropical air entering the plains of North America with southern cyclones is also slowly transformed due to the high speed of its movement, high moisture content and continuous low clouds.

In winter, the consequence of intense meridional circulation of air masses is the so-called “jumps” of temperatures, their large inter-day amplitude, especially in areas where cyclones are frequent: in northern Europe and Western Siberia, Great Plains of North America.

IN cold period fall in the form of snow, a snow cover is formed, which protects the soil from deep freezing and creates a supply of moisture in the spring. The depth of the snow cover depends on the duration of its occurrence and the amount of precipitation. In Europe, stable snow cover on flat areas forms east of Warsaw, its maximum height reaches 90 cm in the northeastern regions of Europe and Western Siberia. In the center of the Russian Plain, the height of snow cover is 30-35 cm, and in Transbaikalia - less than 20 cm. On the plains of Mongolia, in the center of the anticyclonic region, snow cover forms only in some years. Lack of snow along with low winter temperature air causes the presence of permafrost, which is not observed anywhere else on the globe at these latitudes.

In North America, snow cover is negligible on the Great Plains. To the east of the plains, tropical air increasingly begins to take part in frontal processes; it aggravates frontal processes, which causes heavy snowfalls. In the Montreal area, snow cover lasts up to four months, and its height reaches 90 cm.

Summer in the continental regions of Eurasia is warm. The average July temperature is 18-22 °C. In the arid regions of south-eastern Europe and Central Asia The average air temperature in July reaches 24-28 °C.

In North America, continental air in summer is somewhat colder than in Asia and Europe. This is due to the smaller latitudinal extent of the continent, the large ruggedness of its northern part with bays and fjords, the abundance of large lakes, and the more intense development of cyclonic activity compared to the interior regions of Eurasia.

In the temperate zone, the annual precipitation on the flat continental areas varies from 300 to 800 mm; on the windward slopes of the Alps more than 2000 mm falls. Most of the precipitation falls in summer, which is primarily due to an increase in the moisture content of the air. In Eurasia, there is a decrease in precipitation across the territory from west to east. In addition, the amount of precipitation decreases from north to south due to a decrease in the frequency of cyclones and an increase in dry air in this direction. In North America, a decrease in precipitation across the territory is observed, on the contrary, towards the west. Why do you think?

Most of the land in the continental temperate climate zone is occupied by mountain systems. These are the Alps, Carpathians, Altai, Sayans, Cordillera, Rocky Mountains etc. In mountainous areas climatic conditions differ significantly from the climate of the plains. In summer, the air temperature in the mountains drops quickly with altitude. In winter, when cold air masses invade, the air temperature on the plains is often lower than in the mountains.

The influence of mountains on precipitation is great. Precipitation increases on windward slopes and at some distance in front of them, and decreases on leeward slopes. For example, differences in annual precipitation between western and eastern slopes Ural mountains in some places they reach 300 mm. In mountains, precipitation increases with altitude to a certain critical level. In the Alps, the highest precipitation occurs at altitudes of about 2000 m, in the Caucasus - 2500 m.

Subtropical climate zone

Continental subtropical climate determined by the seasonal change of temperate and tropical air. The average temperature of the coldest month in Central Asia is below zero in some places, in the northeast of China -5...-10°C. The average temperature of the warmest month ranges from 25-30 °C, with daily maximums exceeding 40-45 °C.

The most strongly continental climate in the air temperature regime is manifested in the southern regions of Mongolia and northern China, where the center of the Asian anticyclone is located in the winter season. Here the annual air temperature range is 35-40 °C.

Sharply continental climate in the subtropical zone for the high mountain regions of the Pamirs and Tibet, the altitude of which is 3.5-4 km. The climate of the Pamirs and Tibet is characterized by cold winter, cool summers and little rainfall.

In North America, the continental arid subtropical climate is formed in closed plateaus and in intermountain basins located between the Coast and Rocky Ranges. Summers are hot and dry, especially in the south, where the average July temperature is above 30 °C. The absolute maximum temperature can reach 50 °C and above. A temperature of +56.7 °C was recorded in Death Valley!

Humid subtropical climate characteristic of the eastern coasts of continents north and south of the tropics. The main areas of distribution are the southeastern United States, some southeastern parts of Europe, northern India and Myanmar, eastern China and southern Japan, northeastern Argentina, Uruguay and southern Brazil, the coast of Natal in South Africa and the eastern coast of Australia. Summer in the humid subtropics is long and hot, with temperatures similar to those in the tropics. The average temperature of the warmest month exceeds +27 °C, and the maximum is +38 °C. Winters are mild, with average monthly temperatures above 0 °C, but occasional frosts have a detrimental effect on vegetable and citrus plantations. In the humid subtropics, average annual precipitation amounts range from 750 to 2000 mm, and the distribution of precipitation across seasons is quite uniform. In winter, rain and rare snowfalls are brought mainly by cyclones. In summer, precipitation falls mainly in the form of thunderstorms associated with powerful inflows of warm and humid oceanic air, characteristic of the monsoon circulation of East Asia. Hurricanes (or typhoons) occur in late summer and fall, especially in the Northern Hemisphere.

Subtropical climate with dry summers, typical for the western coasts of continents north and south of the tropics. In Southern Europe and North Africa, such climatic conditions are typical for the coasts Mediterranean Sea, which was the reason to call this climate also Mediterranean. The climate is similar in southern California, central Chile, extreme southern Africa and parts of southern Australia. All these areas have hot summers and mild winters. As in the humid subtropics, there are occasional frosts in winter. In inland areas, summer temperatures are significantly higher than on the coasts, and often the same as in tropical deserts. In general, clear weather prevails. In summer, there are often fogs on the coasts near which ocean currents pass. For example, in San Francisco, summers are cool and foggy, and the warmest month is September. The maximum precipitation is associated with the passage of cyclones in winter, when the prevailing air currents mix towards the equator. The influence of anticyclones and downdrafts of air over the oceans cause the dry summer season. The average annual precipitation in a subtropical climate ranges from 380 to 900 mm and reaches maximum values ​​on the coasts and mountain slopes. In summer there is usually not enough rainfall for normal tree growth, and therefore a specific type of evergreen shrubby vegetation develops there, known as maquis, chaparral, mali, macchia and fynbos.

Equatorial climate zone

Equatorial climate type distributed in equatorial latitudes in the Amazon basin in South America and the Congo in Africa, on the Malacca Peninsula and on the islands South-East Asia. Usually average annual temperature about +26 °C. Due to the high midday position of the Sun above the horizon and the same length of day throughout the year, seasonal temperature fluctuations are small. Wet air, cloud cover and dense vegetation cover prevent night cooling and keep maximum daytime temperatures below 37 °C, lower than at higher latitudes. The average annual precipitation in the humid tropics ranges from 1500 to 3000 mm and is usually evenly distributed over the seasons. Precipitation is mainly associated with the Intertropical Convergence Zone, which is located slightly north of the equator. Seasonal shifts of this zone to the north and south in some areas lead to the formation of two maximum precipitation during the year, separated by drier periods. Every day thousands of thunderstorms roll over humid tropics. In between, the sun shines in full force.

On the climate (and, therefore, climate zone) influence and shape it, depending on geographical conditions, climate-forming factors. These include: the amount of radiation from the sun reaching a certain surface of the Earth; atmospheric circulation processes; volumes of biomass. These factors that determine climate can vary significantly depending on the latitude of the area. It is latitude that determines at what angle sunlight hits the surface. globe and, accordingly, how intensely the surface located at different distances from the equator will warm up.

The thermal regime of a particular area depends to a large extent on its proximity to the oceans, which act as heat accumulators. On land surfaces bordering the oceans, more mild climate climate zone, compared to the climate in the interior of the continents. Daily and seasonal temperature changes near large volumes of water are more gradual than in a continental climate closer to the center of the continents. There is more rainfall here and the sky is often covered with clouds. In contrast, continental climates are characterized by sharp temperature changes and less rainfall.

A phenomenon associated with the oceans, the sea current, is also the most important factor, which determines the weather on Earth. Carrying warm masses of water around the continents, they warm atmospheric air, bring cyclones with large amounts of precipitation. How radically a current can influence nature can be seen using the example of the North Atlantic Current. In those areas that fall within the zone of its influence, dense forests grow. And in Greenland, located in the same latitudes, there is only a thick layer of ice.

It has no less influence on the climate and topography (which also affects the formation of the climate zone). Everyone knows the footage of climbers climbing mountains, who, starting from green meadows at the foot of the mountain, a few days later stand on snow-capped peaks. This happens due to the fact that with every kilometer above sea level, the ambient temperature drops by 5-6 °C. Besides, mountain systems prevent the movement of both warm and cold air masses. Often the climate on one side and the other of a mountain range can differ significantly. A striking example This is the difference in air temperature and humidity in Sochi and Stavropol, located on opposite sides of the Caucasus Mountains.

To correctly define the concept " climate zone“We need to distinguish between terms such as weather and climate.

Weather is the state of the troposphere at a certain period of time in a specific area. Climate is considered to be the average established weather pattern. What's happened climate zone, what are its varieties?

Climatic zone and its properties.

Climatic zone It is customary to call the latitudinal band, which differs from other bands in the circulation of the atmosphere, as well as the intensity of heating of the Sun.

There are a total of 7 species on the planet climatic zone c, which in turn are divided into main and transition zones. The category of main belts is also commonly called permanent.

Permanent and transitional climatic zones.

Constant (basic) is called climate zone, in which one air mass dominates throughout the whole year. The main types of zones include: temperate, tropical, equatorial and arctic.

Transition zones are characterized by a change in air masses, that is, it becomes hot in the summer and colder in the winter. There are subarctic, subtropical and subequatorial zones.

Equatorial climate zone.

This subspecies of the main climate zone located in the equator region. This is a one-of-a-kind belt that is divided into several parts. Throughout the year it is influenced by the equatorial air mass.

The main features of the equatorial belt:

• high humidity;
• high precipitation (up to 7 thousand mm per year);
• high temperature (from 20°C and above).

Natural area of ​​this climate zone are considered rain forests, which are filled with various poisonous plants and animals.

The Amazonian lowland is located in this belt, equatorial Africa, as well as the Greater Sunda Islands.

Subequatorial climate zone.

This subspecies is transitional climate zone located between the equatorial and tropical zones. Consequently, 2 air masses change on its territory during the year.

IN subequatorial belt Northern Australia, northern South America, the Hindustan Peninsula, and Southeast Asia are located.

Tropical and subtropical zones.

The tropical zone is typical tropical latitudes. Weather in the tropics depends on the height of the sun above the horizon. For the tropical climate zone characterized by sharp temperature changes - from hot to cold.

This counts main reason, according to which the world of flora and fauna is very poor. This subtype of permanent belts includes North Africa, Mexico and the Caribbean islands.

The subtropical zone is located in the middle of the temperate and tropical zones. It is customary to distinguish between the northern and southern subtropical zones. IN summer period tropical heat prevails here, which is characterized by dryness, and in winter there is a cold air mass.

The climate zone characteristic of the Great Chinese Plain, North Africa, North America and southern Japan.

Temperate climate zone.

Distinctive feature temperate zone Temperatures are considered to be able to vary seasonally. For such climate zone negative temperature is typical.

Temperate latitudes contain large parts of Europe, Great Britain, Russia, Canada and the northern United States.

CLIMATE ZONES

Climatic zones.

The climate, like all meteorological quantities, is zonal. There are 7 main and 6 transitional climatic zones.

The main ones include:

equatorial,

two subequatorial (in the northern and southern hemispheres),

two tropical

two moderate

two polar.

The names of transitional zones are closely linked to the names of the main climatic zones and characterize their location on Earth: two subequatorial, subtropical and subpolar (subarctic and subantarctic). The basis for identifying climatic zones is thermal belts and dominant types of air masses and their movement.

In the main zones, one type of air mass dominates throughout the year, and in transitional zones, the types of air masses change in winter and summer due to the change of seasons and shifts in atmospheric pressure zones.

Equatorial belt. Equatorial air predominates throughout the year. Average monthly temperatures are 25-28 ° C, their amplitudes are small, calm or weak winds prevail in the belt, humidity is high, cloudiness is significant, often represented by cumulus and cumulus-thunderstorm (vertically developed) clouds. Precipitation 1000-2000 mm/year. Equatorial belt characterized by two rainy periods in transition seasons, often after the equinoxes, separated by less rainy or short rainless periods, excessive moisture. The equatorial climate is characteristic of the river basin. Amazon (Amazon Lowland, South America), the coast of the Gulf of Guinea and the Congo River basin (West Africa, Congo Lowland), the Malacca Peninsula, the Sunda Islands and New Guinea (borders of the Indian and Pacific oceans).

Subequatorial belts . Air masses change throughout the year. In summer, equatorial air dominates, summer is humid; in winter - tropical, winter is dry. Rainy (summer) and dry (winter) periods are clearly defined. Winter is only slightly cooler than summer, average temperatures vary from 22 to 30 ° C, and temperature amplitudes increase. The annual amount of precipitation varies significantly: if on average it falls 1000-1500 mm, then on the windward slopes of the mountains it can be 6000-10000 mm. Almost all precipitation falls in summer. A subequatorial climate is observed in the Brazilian and Guinean highlands (South America), in Central Africa adjacent to the Congo River basin on all sides, in Hindustan and Indochina (South Asia) and Northern Australia.

Tropical climate zones located on both sides of the tropics, approximately between 18 and 30 ° N. and S. Tropical air (dry air with high temperatures), trade winds predominate (northeast and southeast). The weather is mostly clear, winter is warm, but noticeably colder than summer. The average temperature of the warmest month is +30-35 ° C, the coldest month is not lower than +10 ° C. The tropical zone is characterized by very large daily temperature amplitudes - up to 40 ° C, and the average annual temperature is about 20 ° C. Cloudiness is insignificant, precipitation in the majority There is little precipitation in areas: 50-150 mm/year (with the exception of the eastern parts of the continents, which are under the influence of oceanic trade winds). In the tropical zone there are two climatic regions: 1) dry , desert climate - west and center of continents and 2) wet tropical climate - on eastern coasts continents.

Subtropical climate zones follow the tropical ones and are found approximately between 30 and 40° latitude in the Northern and Southern Hemispheres. In summer, tropical air dominates here, in winter - temperate. Characterized by the presence of dry and wet periods. In these zones, anticyclonic weather prevails in summer (with the exception of monsoon areas). Summer is dry, hot, with an average temperature of about 30 ° C. In winter, cyclonic weather associated with the polar (temperate) front prevails. Winters are humid and warm, but temperatures below 0 °C are also possible. Snow rarely falls, so snow cover does not form. The amount of precipitation is from 200 to 500 mm per year, but on the windward slopes of the mountains it is much higher (Crkvice - 8000 mm, Balkan Peninsula). In subtropical zones there are climatic regions : 1) Mediterranean I - on the western coasts of the continents - the Mediterranean, Central Chile (South America), southwest Australia, California (N. America), the southern coast of Crimea (Europe). It is characterized by clear, dry and hot summers and rainy warm winter; 2) monsoon subtropical - Florida (N.America), Uruguay (South America), Eastern China, Japanese Islands (East Asia). In this area, summers are hot but rainy, winters are relatively cold and dry; 3) subtropical continental climate region, located in the central parts of the continents. Summers are hot and dry, winters are relatively cold with little precipitation (southern Australia, Turkmenistan, Iran, Taklimakan Desert, western China, dry western USA). Certain areas of the subtropical zone have uniform moisture throughout the year: southeast Australia, Tasmania, and the middle part of Argentina (South America).

Temperate climate zones occupy the space between 40°N. and S. and polar circles (66 ° 33 N and S). Throughout the year, moderate air masses dominate here, with arctic and tropical air often invading. The belt is dominated westerly winds , and on the eastern coasts - monsoons. Plays an important role throughout the year cyclonic activity on the polar (temperate) and Arctic (Antarctic) fronts. Precipitation often occurs, mainly of frontal origin. However, anticyclone weather is not uncommon in the temperate zone. Anticyclones bring predominantly dry weather, especially to continental areas in winter. The regime and amount of precipitation in the temperate zone vary and depend on two main factors: proximity to the sea and the nature of the relief. The following pattern can be traced: when moving inland, the amount of precipitation and days with precipitation becomes less. In the northern and western parts of the continents, moisture is excessive (i.e. K > 1.0), and in the southern and central parts it is insufficient (K< 1,0). Наблюдаются существенные температурные различия между летом и зимой, между сушей и морем. Годовая amplitude air temperatures in winter over the continent reach 50-60 ° C, and over the oceans about 15 ° C. In winter, snow falls on the continents, a stable snow cover is formed that lasts for several months. The diversity of temperature and circulation regimes of the temperate zone predetermines its division into 4 climatic regions:

1)maritime temperate climate(western coasts of the continents) with relatively warm winters, cool and cloudy summers with maximum precipitation. This is the big part Western Europe, coastal strip north-west North America, southern Chile (South America);

2) transitional from maritime to continental- most of Europe, Patagonia (South America);

3) continental climate with varying degrees of continentality and maximum precipitation in the warm season(inland USA, south and southeast of Eastern Europe, Siberia, Kazakhstan, Mongolia, etc.);

4) monsoon temperate climate (n and the eastern coasts of the continents) with cold and dry winters, cool and rainy summers ( Far East, Northeast China, North Korea, Japanese Islands, etc.).

Subpolar climate zones (subarctic and subantarctic). There is also a change in air masses: in winter Arctic (Antarctic) air dominates, in summer - air masses of temperate latitudes. Cyclones and anticyclones are frequent, the frequency of which is approximately the same. There is a polar day and a polar night. Winter is long and severe, the average temperature in January (July) is -40 ° C and lower, but in the oceanic parts up to -5-10 ° C. Summer is short and cool, with the temperature of the warmest month not exceeding 10 ° C. There is little precipitation, their annual amount is up to 200 mm and lower, in oceanic areas up to 400 mm/year. Evaporation is very low, so there is excess moisture, the air is damp, there is a lot of cloudiness, there are many days with rain and especially with snow. In any month, temperatures can drop below 0°C and snow can fall. Winds are frequent and strong. The tundras are located in this belt - the northern coast of Eurasia and North America (continental climate), the Commander and Aleutian Islands, as well as the Antarctic islands (oceanic subpolar climate).

Polar climate zones (Arctic and Antarctic). Arctic air dominates in these zones throughout the year. What is atypical for the belts is that in the western part of the Arctic there is intense cyclonic activity over the sea surface and sea temperate air very often invades. An anticyclone dominates over Antarctica. Characteristic is the absence of solar radiation in winter (polar night) and round-the-clock lighting in summer. However, snow and ice surfaces strongly reflect the sun's rays, which here fall at an angle close to 180°, and emit a lot of heat. Air temperature and humidity are very low, average temperatures are negative, only in some places summer months rise to +5 ° C. There are marine arctic and continental Antarctic climates. The latter is particularly harsh. The average temperature recorded here in December (summer) is -32 ° C, and in August (winter) -71 ° C, the maximum temperature rarely rises above - 20 ° C. There is little precipitation, the air is dry, and occasional precipitation occurs. strong winds, especially during transition seasons. The climate does not remain unchanged. That it is changing is evidenced by observational data on the state of the atmosphere over almost 200 years. Information about weather and climate is available in chronicles and in the works of scientists ancient world. Some rocks (coral limestones, coal, salts, band clays, etc.), landforms, remains of organisms, plant pollen. The causes of climate change are many and overlapping, making it difficult to study. In our time big influence The climate is affected by human activity: changes the state of the atmosphere (increased CO 2 content, dust, heat emissions, etc.), the underlying surface (deforestation, creation of reservoirs, irrigation and drainage of territories). The influence of people on the climate can be considered spontaneous and unfavorable.