Earth climate contour map. Lesson “Climatic zones and regions of the Earth. Climate map. Moderate climatic zone

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

The climate affects the living and inanimate nature... Water bodies, soil, vegetation and animals are closely dependent on the climate. Certain sectors of the economy, primarily agriculture, are also highly dependent on the climate.

The climate is formed as a result of the interaction of many factors: the amount of solar radiation entering the earth's surface; circulation of the atmosphere; the nature of the underlying surface. At the same time, climate-forming factors themselves depend on the geographical conditions of a given area, primarily on geographic 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 mode of precipitation is uneven (more in the warm period than in the cold), the cloudiness is low, the winter is cold, the summer is warm, the annual temperature range is large. This climate is called continental because it is typical of places located in the interior of continents. Above the water surface, a maritime climate is formed, which is characterized by: a smooth course of air temperature, with small daily and annual temperature ranges, large clouds, uniform and sufficiently large amount of atmospheric precipitation.

The climate is greatly influenced by sea \u200b\u200bcurrents... 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 Greenland, which lies at about the same latitudes as the Scandinavian Peninsula, but outside the zone of influence of the warm current, all year round covered with a thick layer of ice.

An important role in the formation of the climate belongs relief... You already know that as the terrain rises, the air temperature decreases by 5-6 ° С for every kilometer. Therefore, on the high mountain slopes of the Pamirs, the average annual temperature is 1 ° С, although it is located slightly north of the tropic.

The location of mountain ranges has a great influence on the climate. For instance, Caucasus mountains they delay moist sea winds, and much more precipitation falls on their windward slopes facing the Black Sea than on the leeward ones. At the same time, the mountains serve as an obstacle to cold northern winds.

The climate is also dependent on prevailing winds... On the territory of the East European Plain, westerly winds coming from the Atlantic Ocean prevail throughout almost the entire year, therefore winters in this area are relatively mild.

Areas Of the Far East are under the influence of monsoons. In winter, winds constantly blow from the depths of the mainland. They are cold and very dry, so there is little rainfall. In summer, on the contrary, winds bring a lot of moisture from the Pacific Ocean. In autumn, when the wind dies down from the ocean, the weather is usually sunny and quiet. This is the best time of the year in the area.

Climatic characteristics represent statistical inferences from long-term series of weather observations (in temperate latitudes, 25-50-year series are used; in the tropics, their duration may be shorter), primarily over the following main meteorological elements: atmospheric pressure, wind speed and direction, air temperature and humidity, cloudiness and precipitation. They also take into account the duration of solar radiation, the visibility range, the temperature of the upper layers of the soil and water bodies, the evaporation of water from the earth's surface into the atmosphere, the height and state of the snow cover, various atmospheric phenomena and terrestrial hydrometeors (dew, ice, fog, thunderstorms, blizzards, etc.). In the XX century. the number of climatic indicators included the characteristics of the elements heat balance the earth's surface, such as total solar radiation, radiation balance, heat transfer values \u200b\u200bbetween the earth's surface and the atmosphere, 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.

Climatic zones

Long-term average values \u200b\u200bof meteorological elements (annual, seasonal, monthly, daily, etc.), their sums, frequency of occurrence, etc. are called climatic norms: the corresponding values \u200b\u200bfor individual days, months, years, etc. are considered as deviations from these norms.

Climate maps are called climatic (temperature distribution map, pressure distribution map, etc.).

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

The main climatic zones are:

• equatorial;
• two tropical;
• two moderate;
• arctic and antarctic.

Transitional climatic zones are located between the main zones: subequatorial, subtropical, subarctic, subantarctic. In transitional zones, air masses change with seasons. They come here from neighboring belts, 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, and in the winter - with the climate of the temperate zones. This is due to the seasonal movement of the belts of atmospheric pressure over the earth after the Sun: in the summer - to the north, in the winter - to the south.

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

The variety of climates on Earth

Climate classification provides an ordered system for characterizing climate types, their regionalization and mapping. Let us give examples of the types of climate prevailing over vast territories (Table 1).

Arctic and Antarctic climatic zones

Antarctic and arctic climate dominates in Greenland and Antarctica, where the average monthly temperatures are below 0 ° C. In the dark winter season, these regions do not receive any solar radiation at all, although there are twilight and auroras. Even in summer sun rays fall on the earth's surface at a slight angle, which reduces the effectiveness of heating. Most of the incoming solar radiation is reflected by ice. Both summer and winter, the elevated regions of the Antarctic Ice Sheet are characterized by low temperatures. The climate of the interior of Antarctica is much colder than the climate of the Arctic, because southern mainland is distinguished by its large size and altitude, and the Arctic Ocean softens the climate, despite the widespread distribution of pack ice. In summer, during short warmings, drifting ice sometimes melts. Precipitation on ice sheets falls in the form of snow or small particles of ice fog. The interior regions receive only 50-125 mm of precipitation annually, but more than 500 mm can fall on the coast. 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 blizzards blow from the cold ice sheet, bringing snow to the coast.

Table 1. Climates of the Earth

Climate type	Climatic belt	Average temperature, ° С		Mode and amount of atmospheric precipitation, mm	Circulation of the atmosphere	Territory
Equatorial	Equatorial			During a year. 2000	In the area of \u200b\u200blow atmospheric pressure, warm and humid equatorial air masses are formed	Equatorial regions of Africa, South America and Oceania
Tropical monsoon	Subequa-torial			Mostly during the summer monsoon, 2000		South and Southeast Asia, West and Central Africa, Northern Australia
Tropical dry	Tropical			Throughout the year, 200		North Africa, Central Australia
Mediterranean	Subtropical			Mainly in winter, 500	In summer - anticyclones at high atmospheric pressure; in winter - cyclonic activity	Mediterranean, Southern coast of Crimea, South Africa, Southwest Australia, Western California
Subtropical dry	Subtropical			During a year. 120	Dry continental air masses	Inland continents
Moderate marine	Moderate			During a year. 1000	Westerly winds	Western Eurasia and North America
Moderate continental	Moderate			During a year. 400	Westerly winds	Inland continents
Moderate monsoon	Moderate			Mostly during the summer monsoon, 560		Eastern edge of Eurasia
Subarctic	Subarctic			Throughout the year, 200	Cyclones prevail	Northern outskirts of Eurasia and North America
Arctic (antarctic)	Arctic (Antarctic)			Throughout the year, 100	Anticyclones prevail	Water area of \u200b\u200bthe Arctic Ocean and mainland Australia

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

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

average temperature in January it varies over the territory from -28 to -50 ° С, and in 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 (-71 ° С) was recorded. The air is very dry.

Summer in subarctic belt although short, it is quite warm. The average monthly temperature in July is from 12 to 18 ° C (daily maximum is 20-25 ° C). Over 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 in comparison with the corresponding climate in Asia. There are less cold winters and colder summers.

Moderate climatic zone

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

The constant transfer of sea air is accompanied by large clouds and causes protracted springs, in contrast to the interior of the continental regions of Eurasia.

Winter in temperate the western coasts are warm. The warming influence of the oceans is intensified by the 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 ° С. During incursions of the Arctic air, it can decrease (on the Scandinavian coast to -25 ° C, and on the French coast - to -17 ° C). When tropical air spreads to the north, the temperature rises sharply (for example, it often reaches 10 ° C). In winter, on the western coast of Scandinavia, there are large positive temperature deviations from the average latitudinal temperature (by 20 ° C). The temperature anomaly on the Pacific coast of North America is less and does not exceed 12 ° C.

Summers are 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, cloudy and rainy weather is typical for all seasons. There are especially many cloudy days on the west coast of North America, where cyclones are forced to slow down in front of the Cordillera mountain systems. In this regard, the weather regime in the south of Alaska, where there are no seasons in our understanding, is characterized by great uniformity. 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, broadleaf forests, and in conditions of excess - conifers. The lack of summer heat reduces the upper boundary of the forest in the mountains to 500-700 m above sea level.

Moderate climate of the eastern coasts of the continents has monsoon features and is accompanied by a seasonal change of winds: in winter, northwestern streams prevail, in summer - southeastern ones. It is well defined on the east coast of Eurasia.

In winter, with a north-westerly 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 regions of the coast. The north of the Amur Region, Sakhalin and Kamchatka are often influenced by cyclones moving over the Pacific Ocean. Therefore, in winter there is a thick snow cover, especially in Kamchatka, where its maximum height reaches 2 m.

In summer, with a southeasterly wind on the coast of Eurasia, maritime temperate air spreads. Summers are warm, with an average July temperature of 14 to 18 ° C. Precipitation is frequent due to cyclonic activity. Their annual number is 600-1000 mm, with most of them falling in summer. Fogs are frequent at this time of the year.

Unlike Eurasia, the east coast of North America is characterized by marine features climate, which are expressed in the predominance of winter precipitation and the marine type of annual air temperature variation: 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. Winters here are mild, snowy, wet and windy. In snowy winters, the height of snowdrifts reaches 2.5 m. Ice often occurs with a southerly wind. Therefore, some streets in some cities in eastern Canada have iron railings for pedestrians. Summers are cool and rainy. Annual precipitation is 1000 mm.

Moderate 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.

A feature of the temperate continental climate is a large annual amplitude of air temperature, which can reach 50-60 ° C. IN winter months with a negative radiation balance, the earth's surface is cooled. The cooling effect of the land surface on the surface layers of air is especially great in Asia, where a powerful Asian anticyclone forms in winter and cloudy, calm weather prevails. The temperate continental air forming in the area of \u200b\u200bthe anticyclone has a low temperature (-0 ° ...- 40 ° C). In valleys and basins, due to radiation cooling, the air temperature can drop to -60 ° C.

In the middle of winter, the continental air in the lower layers becomes even colder than the arctic. This very cold air of the Asian anticyclone spreads to Western Siberia, Kazakhstan, 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 are less severe here, and their severity does not increase towards the center of the mainland, 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 continental territory. In North America, the Cordillera mountain ranges are the natural boundary that separates the coast from maritime climate from inland areas with a continental climate. In Eurasia, a temperate continental climate is formed over a vast land area, approximately from 20 to 120 ° E. Unlike North America, Europe is open to free penetration of sea air from the Atlantic deep into hinterland... This is facilitated not only by the western transport of air masses, which prevails in the temperate latitudes, but also by the flat relief, strong indented coasts and deep penetration into the land of the Baltic and North Seas. Therefore, over Europe, a temperate climate of a lesser degree of continentality is formed compared to Asia.

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

The wide front of Eurasia and North America facing the Arctic basin contributes to the deep penetration of cold air masses to the continents throughout the year. Intense meridional air mass transfer 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 transforming due to its high speed of movement, high moisture content and continuous low clouds.

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

In the cold period, it falls in the form of snow, a snow cover forms, which protects the soil from deep freezing and creates a moisture reserve in spring. The depth of the snow cover depends on the duration of its occurrence and the amount of precipitation. In Europe, stable snow cover in the flat area forms to the east of Warsaw, its maximum height reaches 90 cm in the north-eastern regions of Europe and Western Siberia. In the center of the Russian Plain, the height of the 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 is formed only in separate years... The absence of snow, along with low winter air temperatures, leads to the presence of permafrost, which is no longer observed anywhere on the globe under these latitudes.

In North America on the Great Plains, snow cover is negligible. 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, the snow cover lasts up to four months, and its height reaches 90 cm.

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

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

In the temperate zone, the annual precipitation on the flat territory of the continents varies from 300 to 800 mm, more than 2000 mm falls on the windward slopes of the Alps. Most of the precipitation falls in summer, which is primarily associated with 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 air dryness in this direction. In North America, a decrease in precipitation across the territory is noted, on the contrary, towards the west. Why do you think?

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

The influence of mountains on precipitation is great. Precipitation increases on the windward slopes and at some distance in front of them, and decreases on the leeward slopes. For example, differences in annual precipitation between the western and eastern slopes Ural mountains in some places they reach 300 mm. In the mountains, precipitation increases with height to a certain critical level. In the Alps, the level of the greatest amount of precipitation falls at an altitude 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 places, in northeast China -5 ...- 10 ° С. The average temperature of the warmest month is in the range of 25-30 ° С, while daily highs can exceed 40-45 ° С.

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

Sharply continental climate in the subtropical zone for high mountain areas Pamir and Tibet, which are 3.5-4 km high. The climate of the Pamirs and Tibet is characterized by cold winters, cool summers and low rainfall.

In North America, a continental arid subtropical climate forms in enclosed plateaus and intermontane basins located between the Coastal 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. In Death Valley, a temperature of +56.7 ° C was recorded!

Humid subtropical climate characteristic of the eastern coasts of the continents to the north and south of the tropics. The main areas of distribution are the southeastern United States, some southeastern regions of Europe, northern India and Myanmar, eastern China and southern Japan, northeastern Argentina, Uruguay and southern Brazil, the coast of Natal province in South Africa and the east coast of Australia. Summers in the humid subtropics are long and hot, with the same temperatures as in the tropics. The average temperature of the warmest month exceeds +27 ° С, and the maximum temperature is +38 ° С. Winters are mild, with average monthly temperatures above 0 ° C, but occasional frosts have a detrimental effect on vegetable and citrus plantations. In humid subtropics, the average annual precipitation ranges from 750 to 2000 mm, the distribution of precipitation over the seasons is quite even. In winter, rains and rare snowfalls are brought mainly by cyclones. In summer, precipitation occurs 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 of the western coasts of the continents north and south of the tropics. In southern Europe and North Africa such climatic conditions are typical for the coast Mediterranean Sea, which was the reason to call this climate also mediterranean... A similar climate is found in southern California, central Chile, in the extreme south of Africa and in several areas in southern Australia. All these areas have hot summers and mild winters. As in the humid subtropics, there are occasional frosts in winter. Inland temperatures are much higher in summer than on coasts and are often the same as in tropical deserts. In general, clear weather prevails. In summer, fogs are common on the coasts near which ocean currents pass. For example, in San Francisco, summers are cool, 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 over the oceans are responsible for the dryness of the summer season. Average annual precipitation in a subtropical climate ranges from 380 to 900 mm and reaches its maximum values \u200b\u200bon the coasts and slopes of the mountains. In summer, there is usually not enough rainfall for the normal growth of trees, and therefore a specific type of evergreen shrub vegetation develops there, known as maquis, chaparral, mal and, macchia and finbosh.

Equatorial climate zone

Equatorial type of climate distributed in equatorial latitudes in the Amazon basins in South America and Congo in Africa, on the Malacca Peninsula and on the islands of Southeast Asia. Typically, the average annual temperature is about +26 ° C. Due to the high noon standing of the Sun above the horizon and the same day length throughout the year, seasonal temperature fluctuations are small. Humid air, cloudiness and dense vegetation prevent nighttime cooling and maintain maximum daytime temperatures below +37 ° C, lower than at higher latitudes. Average annual rainfall in the humid tropics ranges from 1,500 to 3,000 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 displacements 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. Thousands of thunderstorms roll over the humid tropics every day. In between, the sun shines in full force.

Climate zones are continuous or discontinuous regions that run parallel to the planet's latitudes. They differ among themselves in terms of air circulation and the amount of solar energy. Terrain relief, proximity to or are also important climate-forming factors.

According to the classification of the Soviet climatologist B.P. Alisov, there are seven main types of the Earth's climate: equatorial, two tropical, two temperate, and two polar (one each in the hemispheres). In addition, Alisov identified six intermediate belts, three in each hemisphere: two subequatorial, two subtropical, as well as subarctic and subantarctic.

Arctic and Antarctic climate zone

Arctic and Antarctic climate zone on the world map

The polar region adjacent to the North Pole is called the Arctic. It includes the territory of the Arctic Ocean, the outskirts and Eurasia. The belt is represented by ice and, which are characterized by long, severe winters. The maximum summer temperature is + 5 ° C. Arctic ice affects the Earth's climate as a whole, preventing it from overheating.

The Antarctic belt is located in the very south of the planet. The surrounding islands are also under his influence. There is a pole of cold on the mainland, so winter temperatures average -60 ° C. Summer rates do not rise above -20 ° C. The territory is located in the arctic desert zone. The mainland is almost completely covered with ice. Land areas are found only in the coastal zone.

Subarctic and Subantarctic climatic zone

Subarctic and Subantarctic climate zone on the world map

The subarctic zone includes Northern Canada, southern Greenland, Alaska, northern Scandinavia, northern regions of Siberia and the Far East. The average winter temperature is -30 ° C. With the arrival of a short summer, the mark rises to + 20 ° C. In the north of this climatic zone dominates, which is characterized by high air humidity, boggy and frequent winds. The south is located in the forest-tundra zone. The soil has time to warm up over the summer, so shrubs and woodlands grow here.

Within the subantarctic belt are the islands of the Southern Ocean near Antarctica. The zone is subject to seasonal influence of air masses. In winter, arctic air dominates here, and in summer masses come from temperate zone... The average winter temperature is -15 ° C. Storms, fogs and snowfalls often occur on the islands. In the cold season, the entire water area is occupied by ice, but with the onset of summer they melt. Warm months average -2 ° C. The climate can hardly be called favorable. Vegetable world represented by algae, lichens, mosses and herbs.

Moderate climatic zone

Temperate climate zone on the world map

In the temperate zone lies a quarter of the entire surface of the planet: North America, and. Its main feature is the clear expression of the seasons of the year. The prevailing air masses give high humidity and low pressure. Average winter temperatures are 0 ° C. In the summer, the mark rises above fifteen degrees. Cyclones prevailing in the northern part of the zone provoke snow and rain. Most of the rainfall occurs as summer rain.

Territories inland are prone to droughts. represented by alternating forests and arid regions. In the north, it grows, the flora of which is adapted to low temperatures and high humidity... It is gradually replaced by a zone of mixed deciduous forests. A strip of steppes in the south encircles all continents. The semi-desert and desert zone covers western North America and Asia.

The temperate climate is subdivided into the following subtypes:

• nautical;
• moderate continental;
• sharply continental;
• monsoon.

Subtropical climate zone

Subtropical climate zone on the world map

In the subtropical zone is part Black Sea coast, southwest and, north and south. In winter, the territories are influenced by the air moving from the temperate zone. The mark on the thermometer rarely drops below zero. In summer, the climatic zone is influenced by subtropical cyclones, which warm the earth well. Humid air prevails in the eastern part of the continents. There are long summers and mild winters without frost. The western coasts are characterized by dry summers and warm winter.

In the interior regions of the climatic zone, temperatures are much higher. The weather is almost always clear. Most precipitation occurs during the cold season, when air masses are shifted to the side. On the coasts, there are hard-leaved forests with undergrowth of evergreen shrubs. In the northern hemisphere, they are replaced by a zone of subtropical steppes, smoothly flowing into the desert. In the southern hemisphere, the steppes become deciduous and deciduous forests. Mountainous areas are represented by forest-meadow zones.

In the subtropical climatic zone distinguish the following subtypes of climate:

• subtropical oceanic climate and Mediterranean climate;
• subtropical inland climate;
• subtropical monsoon climate;
• the climate of high subtropical highlands.

Tropical climate zone

Tropical climate zone on the world map

The tropical climatic zone covers separate territories in all but Antarctica. An area of \u200b\u200bincreased pressure dominates the oceans all year round. Because of this, there is little rainfall in the climatic zone. Summer temperatures in both hemispheres exceed + 35 ° C. Average winter temperatures are + 10 ° C. Average daily temperature fluctuations are felt in the interior of the continents.

Most of the time there is clear dry weather here. Most of the precipitation occurs in the winter months. Significant temperature changes provoke dust storms. On the coasts, the climate is much milder: winters are warm, and summers are mild and humid. There are practically no strong winds, precipitation falls in the calendar summer. Dominant natural areas are rainforests, deserts and semi-deserts.

The tropical climate zone includes the following climate subtypes:

• trade wind climate;
• tropical dry climate;
• tropical monsoon climate;
• monsoon climate on tropical plateaus.

Subequatorial climate zone

Subequatorial climate zone on the world map

The subequatorial climate zone affects both hemispheres of the Earth. During the summer, the zone is influenced by equatorial humid winds. In winter, the trade winds dominate. Average annual temperature is + 28 ° C. Daily temperature drops are insignificant. Most of the precipitation occurs during the warm season under the influence of the summer monsoons. The closer to the equator, the more abundant it rains. In summer, most rivers overflow their banks, and in the winter they dry up completely.

The flora is represented by monsoon mixed forests and woodlands. The foliage on the trees turns yellow and falls off during dry periods. With the arrival of rains, it is restored. Grains and herbs grow in open spaces of savannahs. The flora has adapted to the periods of rains and droughts. Some remote woodlands have not yet been studied by humans.

Equatorial climate zone

Equatorial climate zone on the world map

The belt is located on both sides of the equator. A constant stream of solar radiation forms hot climate... On weather affected by air masses coming from the equator. The difference between winter and summer temperatures is only 3 ° C. Unlike other climatic zones, the equatorial climate remains virtually unchanged throughout the year. Temperature readings do not drop below + 27 ° C. Due to heavy rainfall, high humidity, fog and cloudiness are formed. Strong winds are practically absent, which has a beneficial effect on the flora.

The amount of solar radiation decreases from the equator to the poles, and air masses are formed along the thermal zones, i.e. depending on latitude. By latitude, the climatic zone is also determined - huge territories within which the main climate indicators practically do not change. The climatic zones were determined by the Russian scientist-climatologist B.P. Alisov. Their definition is based on the dominant types of air masses, by which the climatic zones got their name.

Climatic zones are divided into basic and transitional. Where the influence of one type of air masses prevails throughout the year, the main climatic zones have formed. There are only seven of them: equatorial, two tropical, two temperate, arctic and antarctic. The seven main climatic zones correspond to four types of air masses.

In the equatorial climatic zone, low atmospheric pressure and equatorial air masses prevail. The sun here is high above the horizon, which contributes to high air temperatures, and due to the prevalence of ascending air currents and the influence of humid oceanic air masses that come with the trade winds, a lot (1000-3500 mm) of precipitation falls in this belt.

Tropical zones are dominated by tropical air masses, high pressure and low air masses. Tropical air masses are always dry, because the air that comes from the equator in the tropics at an altitude of 10-12 km already contains little moisture. As it sinks, it heats up and becomes even drier. Therefore, it does not often rain here. The air temperature is high. Such climatic conditions contributed to the creation of zones of tropical deserts and semi-deserts here.

The temperate climatic zone is influenced by westerly winds and moderate air masses. The four seasons are clearly defined here. The amount of precipitation depends on the remoteness of territories from the ocean. So, most of all precipitation falls in the western part of Eurasia. They are brought by the westerly winds from the Atlantic Ocean. The farther to the east, the less precipitation, that is, the continentality of the climate increases. In the extreme east, under the influence of the ocean, the amount of precipitation increases again.

The Arctic and Antarctic climatic zones are areas of high pressure that are influenced by katabatic winds. The air temperature rarely rises above 0⁰С. The climatic conditions in both zones are very similar - it is always cold and dry here. There is less than 200 mm of precipitation in a whole year.

Areas where air masses change seasonally twice a year are classified as transitional climatic zones. The prefix "sub" appears in the names of the transition zones, which means "under", i.e. under the main belt. Transitional climatic zones are located between the main zones. There are only six of them: two subequatorial, two subtropical, subarctic and subantarctic.

So, the subarctic belt is located between the arctic and temperate, the subtropical - between the temperate and tropical, subequatorial - between the tropical and equatorial belts. In transition zones, the weather is determined by air masses that come from neighboring main zones and change with seasons. For example, the climate of the subtropical zone in summer is similar to the tropical climate, and in winter - to the climate of the temperate zone. And the climate of the subequatorial zone has signs of an equatorial climate in summer and a tropical climate in winter. In the subarctic zone, moderate air masses determine the weather in summer, and arctic ones in summer.

Thus, climatic zones are located zonally and this is due to the influence of solar radiation. Thus, the type of climate on Earth changes zonal. Climate type is understood as a constant set of climatic indicators characteristic of a certain period of time and a certain territory. But the earth's surface is heterogeneous, therefore, different types of climate can form within climatic zones.

The boundaries of climatic zones do not always coincide with the direction of the parallels. And in some places they deviate significantly to the north or south. This is primarily due to the nature of the underlying surface. Therefore, within the same climatic zone, different types of climate can form. They differ from each other in the amount of precipitation, the seasonality of their distribution and the annual amplitudes of temperature fluctuations. For example, in the temperate zone of Eurasia, there are maritime, continental and monsoon climates. Therefore, the individual climatic zones are further subdivided into climatic regions.

Thus, 13 climatic zones are conventionally distinguished on Earth: 7 of them are basic and 6 are transitional. The definition of climatic zones is based on the air masses prevailing in the region throughout the year. Separate climatic zones (temperate, subtropical, tropical) are also divided into climatic regions. Climatic regions are formed under the influence of the underlying surface within the boundaries of one climatic zone.

Climatic zones.The cycle of heat, moisture and the general circulation of the atmosphere form the weather and climate in the geographic envelope. The types of air masses, the peculiarities of their circulation in different latitudes create conditions for the formation of the Earth's climates. The dominance of one air mass during the year determines the boundaries of climatic zones.

Climatic zones- these are territories that encircle the Earth in a continuous or discontinuous strip; they differ from each other in temperature, atmospheric pressure, amount and mode of precipitation, prevailing air masses and winds. The symmetrical placement of climatic zones relative to the equator is a manifestation of the law of geographic zoning. Allocate the main and transitional climatic zones. The names of the main climatic zones are given according to the prevailing air masses and latitudes in which they are formed.

There are 13 climatic zones: seven main and six transitional. The boundaries of each belt are determined by the summer and winter positions of climatic fronts.

There are seven main climatic zones: equatorial, two tropical, two temperate and two polar (Arctic and Antarctic). In each of the climatic zones, one air mass dominates throughout the year - equatorial, tropical, temperate, arctic (Antarctic), respectively.

Transitional climatic zones are formed between the main zones in each hemisphere: two subequatorial, two subtropical and two subpolar (subarctic and subantarctic). There is a seasonal change in air masses in the transition zones. They come from the neighboring main belts: in summer the air mass of the southern main belt, and in winter - the northern one. The proximity of the oceans, warm and cold currents, and the relief affect the climatic differences within the belts: climatic regions with different types climate.

Characteristics of climatic zones. Equatorial belt formed in the equatorial region as a discontinuous strip dominated by equatorial air masses. Average monthly temperatures from +26 to +28 sС. Precipitation is 1500-3000 mm evenly throughout the year. The equatorial belt is the wettest part of the earth's surface (the Congo basin, the coast of the Gulf of Guinea in Africa, the Amazon basin in South America, the Sunda Islands). There are continental and oceanic types of climate, but the difference between them is small.

For subequatorial belts encircling equatorial belt from the north and south, the monsoon air circulation is characteristic. A feature of the belts is the seasonal change in air masses. Equatorial air prevails in summer, tropical air in winter. There are two seasons: summer wet and winter dry. In summer, the climate is slightly different from the equatorial one: high humidity, abundance of atmospheric precipitation. In the winter season, hot dry weather sets in, grasses burn out, trees shed their foliage. The average air temperature in all months ranges from +20 to +30 ° С. Annual precipitation is 1000-2000 mm, maximum precipitation is in summer.

Tropical belts are between 20¨ and 30¨ s. and y. sh. on both sides of the tropics, where trade winds prevail. (Remember why in tropical latitudes the air sinks and high pressures prevail.) During the year, tropical air masses dominate here with high temperatures... The average temperature of the warmest month is + 30 ... + 35 ¨С, the coldest - not lower than +10 ¨С. In the center of the continents, the climate is tropical continental (desert). Cloudiness is insignificant, precipitation for the most part is less than 250 mm per year. Low precipitation causes the formation of the greatest deserts in the world - the Sahara and Kalahari in Africa, the deserts of the Arabian Peninsula, Australia.

In the eastern parts of the continents, which are influenced by warm currents and trade winds blowing from the ocean, intensified by the monsoons in the summer season, a tropical humid climate is formed. The average monthly temperature in summer is +26 ¨С, in winter +22 ¨С. Average annual rainfall is 1500 mm.

Subtropical belts (25-40¨ N and S) are formed under the influence of tropical air masses in summer and moderate air masses in winter. The western parts of the continents have a Mediterranean climate: summer is dry, hot, the average temperature of the warmest month is +30 30С, and winters are humid and warm (up to + 5 ... + 10 ¨С), but short-term frosts are possible. On the eastern coasts of the continents, a subtropical monsoon climate is formed with hot (+25 ¨C) rainy summers and cool (+8 ¨C) dry winters. The amount of precipitation is 1000-1500 mm. Snow rarely falls. In the central parts of the continents, the climate is subtropical continental, with hot (+30 ¨С) and dry summers and relatively cold winters (+ 6 ... + 8 ¨С) with low precipitation (300 mm). The subtropical humid climate is characterized by a more uniform course of temperatures and precipitation. In summer +20 ¨С, in winter +12 ¨С, precipitation falls 800-1000 mm. (Determine the differences in the climates of the subtropical zones from the climate map.)

Moderate belts stretched in temperate latitudes from 40¨ s. and y. sh. almost to the polar circles. Throughout the year, moderate air masses dominate here, but arctic and tropical air masses can penetrate. In the Northern Hemisphere in the west of the continents, westerly winds, cyclonic activity prevail; in the east - monsoons. As we move deeper into the territory, the annual amplitude of air temperature increases (the coldest month - from + 4 ... + 6 ° С to –48 ° С, and the warmest - from + 12 ° С to + 30 ° С). In the Southern Hemisphere, the climate is mainly oceanic. In the Northern Hemisphere, there are 5 types of climate: maritime, moderate continental, continental, sharply continental, monsoon.

The maritime climate is formed under the influence of westerly winds blowing from the ocean (Northern and Central Europe, western North America, Patagonian Andes of South America). In summer, temperatures are around + 15 ... + 17 ° С, in winter - +5 ° С. Precipitation falls throughout the year and reaches 1000-2000 mm per year. In the Southern Hemisphere, in the temperate zone, an oceanic climate dominates with cool summers, mild winters, heavy rainfall, westerly winds, unstable weather (“roaring” forties).

The continental climate is typical for the interior regions of large continents. A moderately continental, continental, sharply continental climate is formed in Eurasia, and a moderately continental and continental climate in North America. On average, the July temperature varies from + 10 ° С in the north to + 24 ° С in the south. In a temperate continental climate, January temperature decreases from west to east from –5 ° to –10 ° С, in a sharply continental climate - to –35 ... –40 ° С, and in Yakutia below –40 ° С. Annual precipitation in a temperate continental climate is about 500-600 mm, in a sharply continental climate - about 300-400 mm. In winter, with the movement to the east, the duration of stable snow cover increases from 4 to 9 months, and the annual temperature range also increases.

The monsoon climate is best expressed in Eurasia. In summer, a stable monsoon from the ocean prevails, the temperature is + 18 ... + 22 ° С, in winter - –25 ° С. In late summer - early autumn, typhoons from the sea are frequent with gusty winds and heavy rainfall. Winters are relatively dry, as the winter monsoon blows from the land. Precipitation in the form of rains prevails in summer (800-1200 mm).

Subpolar belts (subarctic and subantarctic) located to the north and south of the temperate zone. They are characterized by a change in air masses according to the seasons: in summer, moderate air masses dominate, in winter - Arctic (Antarctic). The continental subarctic climate is typical for the northern outskirts of North America and Eurasia. Summer is relatively warm (+ 5 ... + 10 ° С), short. Winter is harsh (down to –55 ° С). There is a cold pole in Oymyakon and Verkhoyansk (–71 ° С). Small amount of precipitation - 200 mm. Permafrost, excessive moisture are widespread, and significant areas are swampy. The oceanic climate in the Northern Hemisphere is formed in the Greenland and Norwegian Seas, in the Southern Hemisphere - around Antarctica. Cyclonic activity is developed throughout the year. Cool summers (+ 3 ... + 5 ° С), floating sea and continental ice, relatively mild winters (–10 ... –15 ° С). Winter precipitation is up to 500 mm, fogs are constant.

Figure: 16. Typical types of annual

Polar belts (arctic and the course of air temperatures of different antarctic) located around the climatic zones of the poles. The continental climate prevails in Antarctica, Greenland, and the islands of the Canadian Arctic Archipelago. Freezing temperatures throughout the year.

The oceanic climate is observed mainly in the Arctic. The temperatures here are negative, but during the polar day they can reach +2 ° С. Precipitation is 100-150 mm (Fig. 16).

List of references

1. Geography grade 8. Textbook for grade 8 institutions of general secondary education with Russian as the language of instruction / Edited by Professor P. S. Lopukh - Minsk "Narodnaya Asveta" 2014

They appeared in the 70s of the XIX century and had a descriptive character. According to the classification of Moscow State University professor B.P. Alisov, there are 7 types of climates on Earth that make up climatic zones... 4 of them are basic and 3 are transitional. The main types are:

Equatorial climate zone... This type of climate is characterized by the dominance of equatorial ones throughout the year. On the days of the spring (March 21) and autumn (September 21) equinox, the Sun is at its zenith and heats the Earth greatly. The air temperature in this climatic zone is constant (+ 24-28 ° С). 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, therefore in the equatorial climate they are swampy, and thick and high ones grow on them. The climate of this zone is also influenced by the trade winds, bringing here an abundance of precipitation. The equatorial type of climate is formed over the northern regions; on the coast of the Gulf of Guinea, over the basin and upper reaches, including the coast 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 climatic zones (in the Northern and Southern Hemisphere) over the following territories.

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

Mainland climatic zone: a large area is dominated by the region, therefore very little precipitation falls here (from 100-250 mm). The continental tropical climate is characterized by very hot summers (+ 35-40 ° С). In winter, the temperature is much lower (+ 10-15 ° C). Daily temperature fluctuations are great (up to 40 ° C). The absence of clouds in the sky leads to the formation of clear and cold nights (clouds could trap the heat coming from the Earth). Rapid daily and seasonal temperature changes contribute to the resulting mass of sand and dust. They are picked up and can be carried over considerable distances. These dusty sandstorms are a great danger to the traveler.

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

Oceanic tropical climate similar to the equatorial, but differs from it in smaller and stable winds. Summer over the oceans is not so hot (+ 20-27 ° С), and winters are cool (+ 10-15 ° С). Precipitation falls mainly in summer (up to 50 mm). Moderate. There is a significant influence of westerly winds, bringing precipitation throughout the year. Summer in this climatic zone is moderately warm (from + 10 ° С to + 25-28 ° С). Winter is cold (from + 4 ° С to -50 ° С). Annual precipitation ranges from 1000 mm to 3000 mm on the outskirts of the mainland and up to 100 mm in the interior. The differences between the seasons of the year are clearly manifested. This type of climate also forms two belts in the Northern and Southern Hemispheres and is formed over the territories (from 40-45 ° north to the polar circles). Above these territories, an area of \u200b\u200blow pressure, active cyclonic activity is formed. The temperate climate is classified into two subtypes:

1. nautical, which dominates in the western parts of North America, South America, is formed under the direct influence of westerly winds from the ocean to the mainland, therefore it is distinguished by cool summers (+ 15-20 ° С) and warm winters (from + 5 ° С). Precipitation carried by westerly winds falls all year round (from 500 mm to 1000 mm, in the mountains up to 6000 mm);
2. continental, dominant in the central regions of the continents, differs from him. Cyclones penetrate here less often than in the coastal areas, so the summer is warm here (+ 17-26 ° C), and the winter is cold (-10-24 ° C) with a stable many months. Due to the considerable length of Eurasia from west to east, the most striking continental climate is observed in Yakutia, where average January temperatures can drop to -40 ° C and little precipitation falls. This is because the inland areas of the mainland are not affected by the oceans as much as the coasts, where humid winds not only bring precipitation, but also soften the heat in summer and frost in winter.

The monsoon subtype, prevailing in the east of Eurasia to Korea and in the north, in the northeast, is characterized by a change in steady winds (monsoons) over the seasons, which affects the amount and mode of precipitation. In winter, a cold wind blows from the continent, so winters are clear and cold (-20-27 ° С). In summer the winds bring warm rainy weather... In Kamchatka, precipitation ranges from 1600 to 2000 mm.

All subtypes of the temperate climate are dominated by only moderate air masses.

Polar climate... Above 70 ° northern and 65 ° southern latitudes, a polar climate prevails, forming two belts: and. Polar air masses prevail here throughout the year. The sun does not appear at all for several months (polar night) and for several months does not go beyond the horizon (polar day). Snow and ice emit more heat than they receive, so the air is very cooled and does not melt all year round. Throughout the year, these territories are dominated by a high pressure area, so the winds are weak, there are almost no clouds. There is very little precipitation, the air is saturated with small ice needles. When they settle, they add up to only 100 mm of precipitation per year. The average summer temperature does not exceed 0 ° C, and the winter temperature is -20-40 ° C. Prolonged drizzle is typical for summer.

Equatorial, tropical, temperate, polar types of climate are considered the main ones, since within their belts, air masses typical for them dominate throughout the year. Between the main climatic zones there are transitional ones with the prefix "sub" (Latin "under") in the name. In transitional climatic zones, air masses change seasonally. They come here from neighboring belts. This is due to the fact that as a result of the movement of the Earth around its axis, there is a shift of climatic zones to the north, then to the south.

There are three additional types of climate:

Subequatorial climate... In summer, equatorial air masses dominate in this belt, and tropical air masses in winter.

Summer: a lot of precipitation (1000-3000 mm), average + 30 ° С. The sun reaches its zenith in spring and beats down mercilessly.

Winter is cooler than summer (+ 14 ° С). Little precipitation falls. Soils dry out after summer rains, therefore, in the subequatorial climate, in contrast, swamps are rare. The territory is favorable for human settlement, therefore it is here that many centers of the emergence of civilization are located -,. 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, South China,). The southern subequatorial belt includes: South America (lowland,); Africa (center and east of the mainland); (northern coast of the mainland).

Subtropical climate... Here in summer, tropical air masses dominate, and in winter, air masses of temperate latitudes, carrying precipitation, invade here. 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, precipitation is low even in winter. The climate of dry subtropics prevails here with hot summers (up to + 50 ° С) and unstable winters, when frosts down to -20 ° С are possible. In these areas, precipitation is 120 mm or less. The western parts of the continents are dominated by hot, slightly cloudy summers without precipitation and cool, windy and rainy winters. More precipitation falls in the Mediterranean climate than in the dry subtropics. The annual amount of 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 is cold and dry compared to other climates, while summers are hot (+ 25 ° C) and humid (800 mm). This is due to the influence of monsoons blowing from land to sea in winter and from sea to land in summer and bringing precipitation in summer. The monsoon subtropical climate is well expressed only in the Northern Hemisphere, especially on the east coast of Asia. Abundant rainfall in summer makes it possible to develop lush. On fertile soils, it is developed here, supporting the life of more than a billion people.

Subpolar climate... In summer, humid air masses come here from temperate latitudes, so the summer is cool (from +5 to + 10 ° С) and about 300 mm of precipitation falls (in the north-east of Yakutia 100 mm). As elsewhere, precipitation increases on windward slopes. Despite the small amount 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 belt, and significant areas are swampy. In winter, the weather in this climate is influenced by the Arctic and Antarctic air masses, so there are long, cold winters, temperatures can reach as low as -50 ° C. Subpolar climatic zones are located only on the northern outskirts of Eurasia and North America and in Antarctic waters.