climatic zones of the earth. Climatic zones of the Earth General characteristics of the climatic zones of the Earth

Quite diverse and regularly changes with latitude, i.e., zonal. Therefore, climatic zones are distinguished on the planet - latitudinal bands, each of which has a relatively uniform climate. In total, in both hemispheres (Northern and Southern) there are 13 climatic zones (see the atlas map " Climatic zones and regions). Their boundaries are determined by two factors: the amount of solar radiation and superior air masses.

Distinguish between the main and transitional climatic zones. In the main climatic zones, where one of the zonal types of air masses prevails during the year, the equatorial, tropical, temperate, arctic and antarctic zones belong.

Transitional climatic zones are also called sub-belts (from the Latin "sub" - "under", that is, under the main ones). Zonal air masses here change seasonally, coming from neighboring main belts. At the same time, they move with the Sun. So, when the Northern Hemisphere has a warm season, all air masses move to the north, and when it is cold, on the contrary, to the south.
On the map of the atlas "Climatic zones and regions" find the main and transitional climatic zones.

Main types of climate

The type of climate is understood as a constant set of climatic indicators characteristic of a long period of time in a certain area. These indicators are:

• the amount of solar radiation;
• average temperature of the warmest and coldest months;
• annual amplitude of temperature fluctuations;
• prevailing air masses;
• average annual precipitation and the mode of their precipitation.

The equatorial, antarctic and arctic climatic zones have only one type of climate, since they are characterized by constant air masses throughout the year. In the tropical, temperate zones and all climatic subzones, they also distinguish climatic regions. Each of them has its own type of climate.

Equatorial climate zone

At the equator, where the Sun is at its zenith twice a year, high air temperatures are observed throughout the year (+26 ° С - +28 ° С). The annual amplitude is small, about 2 ° -3 ° С. Humid equatorial air masses prevail here. Daily showers cause a large annual amount of precipitation - about 2000-3000 mm. They fall evenly throughout the year.

tropical belts

Over tropical latitudes, the Sun is also at its zenith. (At what time?) The dryness of tropical air masses, in the belt, causes a high transparency of the atmosphere.
Therefore, the amount of solar radiation here is large, which causes very high air temperatures. The usual temperature of the warmest month is +30 ° С, the coldest +15 ° - +16 ° С. the globe- almost +58 ° С. But in winter the surface cools down very quickly, frosts occur on the soil.
Depending on the amount of precipitation in the tropical zone, there are sharp climatic contrasts. In the west and in the interior of the continents, an area of ​​a tropical desert type of climate is formed. Descending air movements prevail here, less than 100 mm of precipitation falls annually.

In the east of the tropical belts of the continents, there is an area of ​​​​a humid tropical climate type. It is dominated by marine tropical air masses coming from the trade winds from the oceans. Therefore, on the eastern coasts, especially in the mountains, several thousand millimeters of precipitation can fall during the year.

temperate zones

In temperate latitudes, the amount of solar radiation fluctuates markedly over 12 months, so the seasons are pronounced. Moderate air masses prevail here throughout the year.

The temperate zone is characterized by significant climatic differences due to the nature of the underlying surface and the peculiarities of the circulation of air masses. There are several climatic regions with corresponding types of climate.
The region of the marine type of climate is formed over the oceanic expanses and on the western margins of the continents. The annual temperature amplitude is to blame here due to the influence of the ocean. The amount of precipitation is high, over 1000 mm per year. Summer is cool, winter is mild.
Region temperate continental climate type(transitional to continental) is typical for the territory of Ukraine. So, in Kyiv, the average temperature in January is -6 ° С, in July +19 ° С, the amount of precipitation is 660 mm per year.

The interior regions of the continents, remote from the ocean, are in the area of ​​the continental type of climate. It is characterized by a small amount of precipitation and a significant annual amplitude of temperature fluctuations. In some areas, for example in Siberia, the difference between the maximum summer and winter temperatures is more than 100° (more than +40°C in summer, -60°C in winter).
On the eastern outskirts of the continents in the temperate zone, an area of ​​\u200b\u200bmonsoon climate type has formed. It is characterized by an annual alternation of two seasons - warm wet and cold dry. The wet summer season with heavy rains is ten times more rainy than the dry one. For example, on the Pacific coast, up to 95% of the annual precipitation sometimes falls in summer. The average July temperature exceeds +20°C, while in winter it drops below -20°C.

Arctic and Antarctic belts have similar climatic conditions. The amount of solar radiation is very high on a polar day, but the high albedo causes the predominance of cold and dry arctic or antarctic air masses in these belts. Temperatures throughout the year are mostly negative. Precipitation is less than 200 mm per year.

The amount of total solar radiation -- 140-150 kcal/cm 2 in year. Radiation balance on the mainland-- 80 kcal/cm 2 per year, on the Ocean - 100-120 kcal/cm 2 in year. Reduced pressure and weak, unstable winds predominate, favoring the development of thermal convection.

Evaporation is equally great both over the Ocean and over the mainland, covered with dense vegetation. The absolute humidity of the air is more than 30 g/zh 3 over land, the relative humidity is 70% even in the driest places. Medium monthly temperature air fluctuates from 24 to 28 °. The amount of precipitation almost everywhere exceeds the possible evaporation and reaches an average of 2000 mm in year. The greatest amount of precipitation generally falls on the periods of equinoxes, but this pattern is not observed everywhere.

Continental and oceanic types of equatorial climate differ very little. In the highland equatorial climate, the temperature is somewhat lower, the amount of precipitation is less (due to a decrease in moisture content with altitude). At an altitude of 4500 m lies the boundary of the belt of eternal snows.

Climates of subequatorial belts (tropical monsoon belts). This climate is composed, as it were, of two climatic regimes: in the summer hemisphere, the equatorial monsoon is directed from the equator and brings moisture; in the winter hemisphere, the monsoon blows towards the equator from the tropics, and the air humidity decreases.

Continental subequatorial climate formed on all continents. The boundary of the equatorial monsoons in the inner parts of the continents lies on the average at about 18°N. sh. The border goes especially far from the equator in Asia (Indostan, Indochina).

The continental subequatorial climate is characterized by wet summers, dry winters and dry hot springs. On the plains, as you move away from the equator, the amount of precipitation decreases. The annual temperature variation has two minimums (in winter and summer) and two maximums (in spring and autumn). Some decrease in temperature in summer is caused by the influence of equatorial air, which at this time is several (up to 5) degrees colder than tropical air. Precipitation rarely exceeds 2000 mm in year.

In mountainous areas, the temperature decreases with height, but the character annual course meteorological elements is preserved. On the slopes that take over the equatorial monsoons, the amount of precipitation increases very sharply, reaching the maximum amount.

The oceanic subequatorial climate is observed on all oceans in the northern hemisphere, in the southern - over the Indian and western parts of the Pacific and Atlantic oceans. The boundary of its distribution lies on average about 12 ° latitude. Tropical cyclones occur more frequently near this boundary.

Summer in the oceanic subequatorial climate is more humid and more (by 2-3°) warmer than winter. It differs from the continental variety of this climate by higher air humidity and lower temperature.

Climates of the tropical zones.

Annual amount total radiation due to low cloudiness in the tropical zone more than in the equatorial zone: on the mainland - 180-200 kcal/cm 2 per year, on the Ocean - 160 kcal/cm 2 V year. However, due to the fact that the effective radiation is also very large, the radiation balance is only 60 kcal/cm 2 per year on the mainland and 80-100 kcal/cm 2 per year on the ocean.

In anticyclones over the oceans and in baric depressions of thermal origin over the continents, tropical air is formed, which differs from the air at the equator by lower humidity. For continental tropical air, this is explained by very low evaporation, for marine air, by the stable stratification of the trade winds (trade wind inversion), which interferes with vertical exchange and the transfer of moisture to higher layers of the troposphere.

The continental tropical climate is very dry and hot, with large daily fluctuations in air temperature (up to 40°). The average annual amplitude of air temperature is about 20°. Relative humidity in summer is about 30%. This climate is typical for the inland deserts of the tropical zone.

With altitude, the air temperature drops, and the amount of precipitation increases. The snow line is located approximately at an altitude of 5300 m, in especially protected areas rising to 6000 m.

The oceanic tropical climate is similar to the equatorial climate, since the daily and annual temperature fluctuations over the ocean are relatively small, and differs from the equatorial climate in less cloudiness and steady winds.

The tropical climate of the western coasts of the continents is very peculiar. It is characterized by relatively low air temperature (18-20°C) and low precipitation (less than 100 mm per year) at high air humidity (80-90%). This is the climate of coastal deserts (Western Sahara, Namib, Atacama, California).

The formation of the climate of the western coast of the continents in the tropical zone is influenced by cold currents and air inflow in the eastern part of the subtropical maximum (anticyclone) from temperate latitudes, which enhance the inversion that exists in the trade winds. As a result, the border temperature inversion is located below the condensation limit and convection does not develop, and therefore clouds do not form and precipitation does not fall. The annual temperature variation is the same as in the ocean type. Fogs are very frequent, breezes are developed.

With height, the air temperature first increases slightly (since the influence of the cold current decreases), then decreases; rainfall does not increase.

The tropical climate of the eastern coasts of the continents differs from the climate of the western coasts by higher temperatures and more precipitation. Thanks to the influence warm current and air brought in the western part of the anticyclone from the equator, the trade wind inversion is weakened and does not prevent convection.

In the mountains on the windward slopes, there is more precipitation, but their amount does not increase with height, since the trade winds are wet only in the lower layer. There is little precipitation on the leeward slopes.

Climates of subtropical zones

In winter, the radiation regime and the nature of circulation develop almost the same way as in the temperate zone, in summer - the same way as in the tropical zone.

Compared to the tropical zone, the annual amount of solar radiation decreases by about 20%, its seasonal fluctuations become more noticeable.

In summer, anticyclones are well expressed over the oceans, and areas of low pressure over the continents. In winter, cyclonic activity prevails in the subtropical zone.

Continental subtropical climate. Summer is hot and dry. average temperature summer months 30° and above, maximum over 50°. Winter is relatively cold, with precipitation. Annual rainfall around 500 mm, and on the windward slopes of the mountains - four or five times more. Snow falls in winter, but a stable snow cover does not form.

With height, the amount of precipitation increases. The air temperature drops, and above 2000 m above sea level in winter, snow cover remains for a short time.

The oceanic subtropical climate differs from the continental subtropical climate in a more uniform annual variation in air temperature. The average temperature of the warmest month is about 20°, the coldest is about 12°.

Subtropical climate of the western coasts of the continents (Mediterranean). Summer is not hot, dry. Winter is relatively warm and rainy. In summer, the coast falls under the influence of the eastern periphery of the subtropical anticyclone. In winter, cyclonic activity dominates here.

The subtropical climate of the eastern coasts has a monsoon character. Winters are cold and dry compared to other climates in this zone, while summers are hot and humid. This climate is well expressed only in the northern hemisphere, and especially on the east coast of Asia.

Climates of temperate zones.

The annual average radiation balance is two times less than in the tropical zone, which largely depends on cloud cover. At the same time, in summer it differs little from the radiation balance of the tropical zone, while in winter the radiation balance on the mainland is negative. The development of cyclonic activity provides meridional air transport. Precipitation is mainly associated with the passage of cyclones.

Continental temperate climate -- climate of the continents of the northern hemisphere. Summers are warm (can be hot), winters are cold with stable snow cover.

Radiation balance on average per year 20-30 kcal/cm 2 , in the summer months it differs little from the tropical (6 kcal/cm 2 per month), and in winter it is a negative value (-1 kcal/cm 2 per month).

In summer, over the continents, there is an intensive transformation of air masses coming from the oceans and from the north. The air is heated, additionally moistened due to the moisture evaporated from the surface of the mainland. In winter, the air is cooled in anticyclones. The temperature falls below -- 30°. Precipitation is higher in summer, but prolonged air transformation can lead to drought.

In the mountains in summer it is much colder than on the plain, and in winter on the plain (as a result of the entry of cold air masses) it is often colder than in the mountains. On the slopes of the mountains, especially on the western ones, facing towards prevailing winds, there is more precipitation than in the plains.

Oceanic temperate climate. The radiation balance of the surface of the oceans on average per year is 1.5 times greater than on the continents. Warm currents bring to temperate latitudes almost as much heat as the radiative balance provides. About 2/3 of the heat is spent on evaporation, the rest goes to warm the atmosphere (turbulent heat transfer) in winter.

Winter over the oceans is much warmer than over the continents, summer is cooler. Cyclonic activity is developed throughout the year.

The temperate climate of the western coasts of the continents is formed under the influence of the western transfer of air from the Ocean to the mainland; differs from the continental climate by smaller annual temperature fluctuations. Precipitation falls fairly evenly in all seasons.

The temperate climate of the eastern coasts of the continents is due to the movement of air from the Ocean to the mainland in summer, and from the mainland to the Ocean in winter. Summers are rainy, winters are dry and cold. Cold currents lower summer temperature air, in spring and early summer they contribute to the formation of fogs.

Climates of the subarctic and subantarctic belts

Continental subarctic climate formed only in the northern hemisphere. Radiation balance 10-12 kcal/cm 2 in year. Summer is relatively warm, short, winter is severe. The annual amplitude of temperature fluctuations is very large. Precipitation is low (less than 200 mm in year). In summer, northerly winds prevail. Coming from the north and transforming over the mainland, the air approaches in its qualities to the Arctic.

In the mountains in winter there is a powerful inversion. The differences between summer and winter temperatures are very great in relief depressions, where air exchange is weakened.

The oceanic subarctic and subantarctic climate does not have sharp differences between winter and summer temperatures. The annual temperature amplitude is not more than 20°. Cyclonic activity is developed throughout the year.

Climates of the Arctic and Antarctic belts

The radiation balance for the year is close to zero on average. The snow cover does not melt all year round. The high reflectivity of snow leads to the fact that even in summer the radiation balance is very small. So, on st. Pionerskaya (70°S) with total radiation in December 24 kcal/cm 2 per month radiation balance on the snow surface is less than 2 kcal.

The predominance of anticyclonic weather contributes to the constant cooling of the air in central regions Arctic and Antarctic. There are few rainfalls. However, precipitation and moisture condensation on the cold snow surface together exceed evaporation.

The continental polar climate is well expressed in the southern hemisphere. It is characterized by very severe winters and cold summers. All months have a negative average temperature. The minimum temperature recorded is -88.3°.

Oceanic polar climate - the climate of the northern polar regions, which forms above the surface of the ocean, covered with ice. In the arrival of heat in winter, a significant role is played by the heat of ocean waters, penetrating through the ice. From October to April the radiation balance is negative, from May to September it is positive.

The average January temperature in the center of the Arctic (-40°C) is higher than in northeast Asia. In summer, as a result of the loss of a large amount of heat for the melting of snow and ice and for evaporation, the temperature is about 0 °. The weather in summer is mostly cloudy. Precipitation is low (about 100 mm in year).

Main questions. What is a climate zone? What features of the climate are characteristic of each of the climatic zones? What effect does climatic conditions have on population distribution?

climatic (gr. klimatos - inclination) differences on Earth are directly related to the inclination of the sun's rays to earth's surface. Climatic zoning is manifested in the placement of climatic zones (Fig. 1) Climatic zones are territories that are continuous or interruptedstopband encircle the earth. They differ from each other in temperature, atmospheric pressure, air masses, prevailing winds, amount and mode of precipitation. They stretch from west to east and replace each other from the equator to the poles. stand out main And transitional climatic zones. In the main climatic zones, one type dominates throughout the year. air mass. In transitional climatic zones - 2 types of air masses. They change with the seasons. Other factors also influence the distribution of temperatures and precipitation within the belts: the proximity of the oceans, warm and cold currents, and relief. Therefore, large differences are observed within the climatic zones and climatic regions are distinguished. Each of them has a certain type of climate.

Main climatic zones correspond to the distribution of four main types of air masses: equatorial, two tropical, two temperate, arctic and antarctic climatic zones (think about their names).

Between the main belts are located transitional climatic zones: two subequatorial, two subtropical, subarctic and subantarctic. Their name depends on the prevailing types of air masses, and the prefix "sub" (lat. sub - under) indicates a secondary role in the general circulation of the atmosphere. For example, subequatorial means located next to the equatorial. Air masses in transitional zones change seasonally: in winter, air masses of the main belt, neighboring from the pole, prevail, in summer - from the side of the equator. (rice.).

equatorial belt formed in the region of the equator between 5 ° S. latitude - 10 ° N sh. During the year, equatorial air masses prevail here. There are always high temperatures and high rainfall. Average monthly temperatures are from –+25 to +28 °C. Precipitation falls 1500-3000 mm per year. This belt is the wettest part of the earth's surface. This is due to the high position of the Sun above the horizon throughout the year and the ascending air currents characteristic of the low pressure belt.

For subequatorial belts(up to about 20 ° N and S) two seasons are characteristic: in summer it dominates equatorial air and very humid, and in winter - tropical air and very dry. In winter, the rays of the Sun fall at right angles in the Southern Hemisphere and therefore, tropical the air mass in this belt comes from the north and dry weather is established. Winter is not much colder than summer. The average air temperature in all months fluctuates between +20 - +30°C. The annual amount of precipitation on the plains is up to 1000-2000 mm, and on the slopes of the mountains - up to 6000-10000 mm. Almost all precipitation falls in summer. (Remember how the trade winds influence climate formation).

tropical belts stretched from 20 to 30 ° north latitude. and y.sh. on both sides of the tropics. Remember why in tropical latitudes ah the air descends and high pressure prevails? Continental tropical air dominates here throughout the year. Therefore, the climate in the central regions of the continents is hot and dry. Trade winds prevail. The average temperature of the warmest month is +30 - +35°С, the coldest - not lower than +10°С. Cloudiness is negligible, there is little precipitation far from the oceans, no more than 50-150 mm per year. Their number increases in the eastern parts of the continents, which are under the influence of warm currents and trade winds blowing from the ocean. In the west and in the center of the continents, the climate is dry, desert. (Identify on the climatic map the differences in the climate of the marginal and central regions of the tropical zone in Africa).

subtropical belts(30-40 ° N and S) are formed under the influence of tropical air masses in summer and moderate in winter. Summers are dry and hot, with an average temperature of the warmest month of about 30°C. Winter is wet, warm, but short-term temperature drops are possible. Snow falls very rarely. This Mediterranean climate. (Explain why on the eastern coasts of the continents the climate subtropical monsoon with hot, rainy summers and cool, dry winters?). In the central parts of the continents, the climate subtropical continental, with hot and dry summers and relatively cold winter with low rainfall.

temperate zones stretched in temperate latitudes from 40 to 60 ° N. latitude. and y.sh. They receive much less solar heat compared to previous climatic zones. Throughout the year, moderate air masses dominate here, but arctic and tropical air penetrates. Western winds prevail in the west, in the east of the continents - monsoons. Climate temperate zone diverse due to the influence of various climatic factors on its territory. A large annual amplitude of air temperature (+22 - 28°С in summer and -22 - 33°С in winter) is typical for the territories of the central part of the mainland. It increases as you move deeper into the continents. Similarly, depending on the position of the territory in relation to the ocean and the relief, different amounts of precipitation fall. Snow falls in winter. On the western coasts of the continents, the climate nautical, with relatively warm and humid winters, cool and overcast summers, and high rainfall. On the east coasts monsoonal climate with cold dry winters and not hot rainy summers, and in the interior - continental climate.

IN subarctic (subantarctic) arctic (antarctic) air dominates in winter, and air masses of temperate latitudes dominate in summer (Determine the geographical position of the belts on the map). The winter is long, with an average winter temperature of up to -40 °C. Summer (winter in the southern hemisphere) is short and cold, with an average temperature of no higher than + 10°C. Annual rainfall is low (300-400 mm) and evaporation is even less. The air is damp, very cloudy.

Approximately a quarter of the world's population lives in the temperate climate zone.Only 5% of the world's population lives in a tropical desert climate.

1. Show the climatic zones on the physical map of the world. 2. Fill in the table "Climatic zones of the Earth": the name of the climatic zone, geographical location, prevailing air masses, climate features (temperature, precipitation). *3. What climate zone is Belarus in? Name the main features of the climate, drawing on knowledge about your area. **4. In which climatic zone (region) are the most favorable conditions for recreation and health improvement of people? Justify your answer.

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

Climate influences living and inanimate nature. are closely related to climate water bodies, soil, vegetation, animals. Individual sectors of the economy, primarily agriculture, are also very dependent on climate.

The climate is formed as a result of the interaction of many factors: the amount of solar radiation entering the earth's surface; atmospheric circulation; the nature of the underlying surface. At the same time, climate-forming factors themselves depend on geographical conditions the area, especially geographical latitude.

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

The climate is greatly influenced by sea ​​currents. Warm currents warm the atmosphere in the areas where they flow. So, 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 approximately at the same latitudes as the Scandinavian Peninsula, but is outside the zone of influence of the warm current, all year round covered with a thick layer of ice.

plays an important role in shaping the climate relief. You already know that with the rise of the terrain for each kilometer, the air temperature drops by 5-6 ° C. Therefore, on the high slopes of the Pamirs, the average annual temperature- 1 ° C, although it is located a little north of the tropic.

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

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

Districts Far East are under the influence of the 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, the 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.

Climate characteristics are statistical inferences from long-term weather records (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, temperature and air humidity, cloudiness and precipitation. The duration of solar radiation, visibility range, temperature are also taken into account. upper layers soil and water bodies, evaporation of water from the earth's surface into the atmosphere, height and condition of snow cover, various atmospheric phenomena and ground-based hydrometeors (dew, ice, fog, thunderstorms, snowstorms, etc.). In the XX century. The climatic indicators included characteristics of the elements of the heat balance of the earth's surface, such as total solar radiation, radiation balance, 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.

Climatic zones

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

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

Depending on the 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 belts there are transitional climatic zones: subequatorial, subtropical, subarctic, subantarctic. In transitional zones, air masses change with the seasons. 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, and in winter - with 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 the tropical zone of Africa, areas of tropical dry and tropical humid climate are distinguished, and in Eurasia, the subtropical zone is divided into areas of the Mediterranean, continental and monsoon climate. In mountainous areas, altitudinal zonation is formed due to the fact that air temperature decreases with height.

Diversity of Earth's climates

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

Arctic and Antarctic climate zones

Antarctic and arctic climate dominates in Greenland and Antarctica, where the average monthly temperatures are below 0 °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 fall on the earth's surface at a slight angle, which reduces the heating efficiency. Most of the incoming solar radiation is reflected by the ice. In both summer and winter, low temperatures prevail in the elevated regions of the Antarctic Ice Sheet. The climate of the interior of Antarctica is much colder than the climate of the Arctic, because southern mainland is different large sizes and heights, and the Arctic Ocean moderates the climate, despite the wide distribution of pack ice. In summer, during short periods of warming, drift ice sometimes melts. Precipitation on ice sheets falls in the form of snow or small particles of ice mist. Inland 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 strong winds, which carry significant masses of snow, blowing it off the slope. Strong katabatic winds with snowstorms blow from the cold glacial sheet, bringing snow to the coast.

subarctic continental climate is formed in the north of the continents (see the climate map of the atlas). In winter, arctic air prevails here, which is formed in the regions high pressure. In the eastern regions of Canada, Arctic air is distributed from the Arctic.

Continental subarctic climate in Asia, it is characterized by the largest annual amplitude of air temperature on the globe (60-65 ° С). The continentality of the climate here reaches its limit.

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

Summer in subarctic belt although short, but quite warm. The average monthly temperature in July ranges from 12 to 18 °C (daily maximum is 20-25 °C). Over the summer, more than half of the annual amount of 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 than the corresponding climate of Asia. It has less cold winters and colder summers.

temperate climate zone

The temperate 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 Cordilleras are a natural boundary separating the coast with a maritime type of climate from the inland regions. The European coast, except for Scandinavia, is open to the free access of temperate maritime air.

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

winter in temperate zone warm on the western coasts. The warming effect 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. Intrusions of arctic air can lower it (on the Scandinavian coast down to -25°C, and on the French coast down to -17°C). With the spread of tropical air 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 latitude (by 20 ° C). The temperature anomaly on the Pacific coast of North America is smaller and does not exceed 12 °С.

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

Even during the day, the air temperature rarely exceeds 30 °C. Cloudy and rainy weather is typical for all seasons due to frequent cyclones. Especially a lot cloudy days happens on the west coast of North America, where cyclones are forced to slow down in front of the Cordillera mountain systems. In connection with this, the weather regime in the south of Alaska is characterized by great uniformity, where there are no seasons in our understanding. Eternal autumn reigns there, and only plants remind of the onset of winter or summer. Annual rainfall ranges from 600 to 1000 mm, and on the slopes of mountain ranges - from 2000 to 6000 mm.

In conditions of sufficient moisture, broad-leaved forests are developed on the coasts, and in conditions of excessive moisture, coniferous forests. The lack of summer heat reduces upper bound forests in the mountains up to 500-700 m above sea level.

The temperate climate of the eastern coasts of the continents It has monsoonal features and is accompanied by a seasonal change of winds: in winter, northwestern flows predominate, in summer - southeast. It is well expressed on the eastern coast of Eurasia.

In winter, with a northwest 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. In the southern regions of the coast, there is little rainfall. 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 thick snow cover, especially in Kamchatka, where its maximum height reaches 2 m.

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

Unlike Eurasia, East Coast North America is characterized sea ​​features climate, which are expressed in the predominance of winter precipitation and marine type the annual course of air temperature: the minimum occurs in February, and the maximum occurs in August, when the ocean is at its 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 snowdrifts reaches 2.5 m. With a southerly wind, icy conditions often occur. Therefore, some streets in some cities in eastern Canada have iron railings for pedestrians. Summers are cool and rainy. The annual rainfall is 1000 mm.

temperate continental climate it is most clearly expressed on the Eurasian continent, especially in the regions of Siberia, Transbaikalia, northern Mongolia, and also on the territory of the Great Plains in North America.

A feature of the temperate 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 a powerful Asian anticyclone forms in winter and cloudy, calm weather prevails. The temperate continental air formed 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 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 here are less severe, 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 is warmer than continental temperate air in Asia.

On the formation of the continental temperate climate have a significant impact geographical features continental territories. In North America, the Cordillera mountain ranges are a natural boundary separating the coast with a maritime climate from the inland regions with a continental climate. In Eurasia, a temperate continental climate is formed over a vast expanse of land, approximately from 20 to 120 ° E. e. Unlike North America, Europe is open to free penetration of sea air from the Atlantic deep into the interior. This is facilitated not only by the western transfer of air masses, which prevails in temperate latitudes, but also by the flat nature of the relief, the strong indentation of the coasts and the deep penetration into the land of the Baltic and North Seas. Therefore, a temperate climate is forming over Europe. lesser degree continentality 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 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 °С in January, -3 °С in Warsaw, -11 °С in Moscow. At the same time, the isotherms over Europe have a meridional orientation.

The orientation of Eurasia and North America with a wide front to the Arctic Basin 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 its high speed of movement, high moisture content and continuous low cloud cover.

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

IN cold period fall in the form of snow, a snow cover forms, which protects the soil from deep freezing and creates a supply of moisture in the spring. The height of the snow cover depends on the duration of its occurrence and the amount of precipitation. In Europe, a stable snow cover on the flat territory is formed 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 the snow cover is 30–35 cm, and in Transbaikalia it is less than 20 cm. On the plains of Mongolia, in the center of the anticyclonic region, snow cover forms only in some years. The absence of snow, along with the low winter air temperature, causes the presence of permafrost, which is no longer observed anywhere on the globe under these latitudes.

In North America, the Great Plains have little snow cover. To the east of the plains, tropical air begins to take part in the frontal processes more and more, it intensifies the frontal processes, which causes heavy snowfalls. In the Montreal area, the 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 dry 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 smaller extent of the mainland in latitude, the large indentation 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 amount of precipitation on the flat territory of the continents varies from 300 to 800 mm; on the windward slopes of the Alps, more than 2000 mm falls. Most of the precipitation falls in the 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 also 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, in the direction to 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, Sayan, Cordillera, Rocky Mountains and others. 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 often turns out to be 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 weakens on the leeward slopes. For example, differences in annual rainfall between the western and eastern slopes Ural mountains sometimes reach 300 mm. In mountains with height, precipitation increases to a certain critical level. In the Alps level most precipitation falls 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 places, in the northeast of China -5...-10°C. The average temperature of the warmest month is in the range of 25-30°C, while daily highs can exceed 40-45°C.

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 °C.

Sharply continental climate in the subtropical zone for the high-mountainous regions of the Pamirs and Tibet, whose height is 3.5-4 km. 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 is formed in closed plateaus and in intermountain 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 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 in South Africa and the east coast of Australia. Summer in the humid subtropics is 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 the humid subtropics, the average annual precipitation ranges from 750 to 2000 mm, the distribution of precipitation over the seasons is quite uniform. In winter, rains 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 monsoon circulation. East Asia. Hurricanes (or typhoons) appear in late summer and autumn, especially in the Northern Hemisphere.

subtropical climate with dry summers is 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 coasts mediterranean sea, which was the reason to call this climate also mediterranean. A similar climate is in southern California, the central regions of Chile, in the extreme south of Africa and in a number of areas in southern Australia. All these regions have hot summers and mild winters. As in the humid subtropics, there are occasional frosts in winter. In inland areas, summer temperatures are much higher than on the coasts, and often the same as in tropical deserts. In general, clear weather prevails. In summer, on the coasts near which ocean currents pass, there are often fogs. 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 downward air currents over the oceans determine the dryness of the summer season. The average annual precipitation in a subtropical climate varies from 380 to 900 mm and reaches maximum values ​​on the coasts and mountain slopes. In the 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 i, macchia and fynbosh.

Equatorial climate zone

Equatorial type of climate distributed in equatorial latitudes in the Amazon basin in South America and the Congo in Africa, on the Malay Peninsula and on the islands of Southeast Asia. Usually mean annual temperature about +26 °С. Due to the high noon position of the Sun above the horizon and the same length of the day throughout the year, seasonal temperature fluctuations are small. Wet air, cloud cover and dense vegetation prevent nighttime cooling and maintain maximum daytime temperatures below +37 °C, lower than at higher latitudes. The average annual rainfall in the humid tropics ranges from 1500 to 3000 mm and is usually evenly distributed over the seasons. Precipitation is mainly associated with the intratropical 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 precipitation maxima during the year, separated by drier periods. Every day, thousands of thunderstorms roll over the humid tropics. In the intervals between them, the sun shines in full force.

In order to define such a concept as a climate zone, it is necessary to distinguish between such concepts as climate and weather.

Climate is usually called the average established weather regime, and the definition of weather sounds like the state of the troposphere at a certain time in a certain place. What is the climate zone, and what are its types?

The concept of the climate zone and its features

The latitudinal band of the earth's surface, which differs from other bands in the intensity of the heating of the Sun and the circulation of the atmosphere, is commonly called the climatic zone.

In total, there are 7 types of climatic zones on planet Earth. But these types also have their own classification, they are divided into two types of climatic zones: basic and transitional. The main belts are also called permanent.

Main and transitional belts

The main or permanent type of climatic zone is considered to be the zone in which one air mass prevails throughout the year. And transitional air masses are characterized by a change in air masses - colder comes in winter, and hotter in summer. The names of transitional belts are written with the prefix "sub".

The permanent climatic zones are considered to be the equatorial, temperate, arctic and tropical zones. And among the variables are subequatorial belt, subtropical and subarctic.

equatorial belt

This type of permanent belt is located in the equatorial region. It is considered to be the only belt that is torn into several parts. Throughout the year, it is under the influence of one air mass, which is also called equatorial.

The main characteristics of the belt: heat (temperature from 20 ° C), a large amount of precipitation - up to 7000 mm per year, high humidity. The natural zone of this belt is moist forests, which are home to many poisonous animals and plants.

TO equatorial belt include the Amazonian lowland, which is located in South America, the Greater Sunda Islands and equatorial Africa.

subequatorial belt

This type of belt is located between tropical and equatorial. This means that during the year two air masses of these belts are replaced on its territory.

The subequatorial belt is characteristic of the north of South America, the Hindustan Peninsula, Northern Australia and Southeast Asia.

Tropical and subtropical belts

The tropical view of the climatic zone is characteristic of tropical latitudes. In the tropics, the weather will depend on the height of the sun above the horizon. The tropical zone is characterized by sudden changes in temperature - from cold to hot.

For this reason, its natural zone is presented in the form of semi-deserts and deserts, vegetation and animal world which are very scarce. The tropical zone is characteristic of Mexico, North Africa, Caribbean, for southern Brazil and central Australia.

The subtropical zone is located between temperate and tropical zones. Separate the southern and northern subtropical belts. In summer, tropical heat reigns here, which is characterized by dryness, and moderate cold air mass dominates in winter.

The subtropical belt is located on the territory of North America (USA), it is typical for the south of Japan, North Africa and the Great Plain of China. And in the southern hemisphere, the subtropical zone occupies the north of New Zealand, the south of Australia and the south of Africa.

Temperate zone

The main characteristic of this belt is that the temperature of one air mass changes seasonally: one can clearly distinguish cold winter, hot summer, spring and autumn. The temperate zone is characterized by negative temperatures.