Climatic zones and regions and their characteristics. Climates of the equatorial zone
Main questions. What is a climate zone? What climate features are characteristic of each climate zone? What influence do climatic conditions have on population distribution?
Climatic (Greek klimatos - tilt) differences on Earth are directly related to tilt sun rays to the earth's surface. Climatic zoning is manifested in the location of climatic zones (Fig. 1) Climatic zones are territories that are continuous or interruptedstopa strip encircles the Earth. They differ from each other in temperature, atmospheric pressure, air masses, prevailing winds, amount and regime of precipitation. They stretch from west to east and replace each other from the equator to the poles. Stand out basic And transitional climatic zones. In the main climatic zones, one type of air mass dominates throughout the year. In transitional climatic zones - 2 types air masses. They change with the seasons. The distribution of temperatures and precipitation within the belts is also influenced by other factors: the proximity of oceans, warm and cold currents, and topography. Therefore, within climate zones there are large differences and climatic regions are distinguished. Each of them has a certain type of climate.
Basic 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 there are transitional climatic zones: two subequatorial, two subtropical, subarctic and subantarctic. Their name depends on the dominant types of air masses, and the prefix “sub” (lat. sub - under) indicates a minor role in the general atmospheric circulation system. For example, subequatorial means located near the equatorial. Air masses in the transition zones change with the seasons: in winter, the air masses of the main belt adjacent to the pole predominate, and in summer, from the equator. (rice.).
Equatorial belt formed in the equator region between 5° south. latitude - 10° north w. During the year, equatorial air masses predominate here. There are always high temperatures here and a large number of precipitation. Average monthly temperatures range from –+25 to +28 °C. Precipitation is 1500-3000 mm per year. This belt is the wettest part of the earth's surface. This is explained by the high position of the Sun above the horizon throughout the year and rising air currents characteristic of the low pressure belt.
For subequatorial belts(approximately up to 20° N and S latitude) two seasons are characteristic: summer is dominated by 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 enters this zone from the north and dry weather sets in. Winter is not much colder than summer. The average air temperature in all months ranges between +20 - +30°C. The annual 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 trade winds influence climate formation).
Tropical zones stretched from 20 to 30° N. and S. on both sides of the tropics. Remember why in tropical latitudes the air sinks and high pressure prevails? Continental tropical air dominates here all year round. Therefore, the climate in the central regions of the continents is hot and dry. The prevailing winds are trade winds. The average temperature of the warmest month is +30 - +35°C, the coldest month is not lower than +10°C. The cloud cover is insignificant, and 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 influenced warm currents and trade winds blowing from the ocean. In the west and in the center of the continents the climate is dry and desert. (Determine by climate map differences in the climate of the marginal and central regions of the tropical zone in Africa).
Subtropical zones(30-40°N and S) are formed under the influence of tropical air masses in summer and moderate ones in winter. Summer is dry and hot, with the average temperature of the warmest month being about 30°C. Winter is humid and warm, but short-term drops in temperature 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 winters with little precipitation.
Temperate zones stretch in temperate latitudes from 40 to 60° N. and S. They get much less solar heat compared to previous climate zones. Throughout the year, moderate air masses dominate here, but arctic and tropical air penetrates. In the west, westerly winds prevail, 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 (in summer - +22 - 28°C, and in winter - -22 - 33°C) is typical for the territories of the central part of the continent. It increases as you move deeper into the continents. Similarly, depending on the location of the territory in relation to the ocean and the topography, different amounts of precipitation fall. In winter it snows. On the western coasts of the continents the climate nautical, with relatively warm and humid winters, cool and cloudy summers, and high rainfall. On the eastern coasts - monsoon climate with cold, dry winters and not hot, rainy summers, but in inland areas - continental climate.
IN subarctic (subantarctic) Arctic (Antarctic) air dominates in winter, and in summer - air masses of temperate latitudes (Determine the geographical location of the belts on the map). Winter is long, with average winter temperatures down to -40 °C. Summer (winter in the southern hemisphere) is short and cold, with an average temperature no higher than + 10°C. The annual precipitation is small (300-400 mm), and evaporation is even less. The air is damp, heavily cloudy.
About 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. Point to physical map world climate zones. 2.Fill out the table " Climate zones Earth": name of the climate zone, geographical location, prevailing air masses, climate features (temperature, precipitation). *3. In what climate zone is Belarus located? Name the main features of the climate, drawing on knowledge about your area. **4.Which climatic zone (region) has the most favorable conditions for people’s recreation and health? Justify your answer.
Quantity solar radiation decreases from the equator to the poles, and air masses are formed along thermal zones, i.e. depending on latitude. Latitude also determines the climatic zone - huge territories within which the main climate indicators practically do not change. Climatic zones were defined by the Russian climatologist B.P. Alisov. Their definition is based on the dominant types of air masses, from which the climatic zones received their name.
Climatic zones are divided into main and transitional. Where the influence of one type of air mass predominates throughout the year, the main climatic zones have formed. There are only seven of them: equatorial, two tropical, two temperate, Arctic and Antarctic. Four types of air masses correspond to the seven main climatic zones.
In the equatorial climate zone, low temperatures prevail Atmosphere pressure and equatorial air masses. The sun here is high above the horizon, which contributes to high air temperatures, and due to the predominance of rising air currents and the influence of moist oceanic air masses that come with the trade winds, a lot of precipitation (1000-3500 mm) 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 descends, it heats up and becomes even drier. Therefore, it does not rain here often. The air temperature is high. Such climatic conditions contributed to the creation of zones here tropical deserts and semi-deserts.
The temperate climate zone is influenced by westerly winds and moderate air masses. There are clearly defined four seasons here. The amount of precipitation depends on the distance of the territory from the ocean. Thus, the most precipitation falls in the western part of Eurasia. They are brought by the western winds from Atlantic Ocean. The further you go to the east, the less precipitation, i.e. the continental climate increases. In the far east, under the influence of the ocean, the amount of precipitation increases again.
The Arctic and Antarctic climate zones are areas of high pressure that are influenced by katabatic winds. The air temperature rarely rises above 0⁰C. Climatic conditions in both zones they are very similar - it is always cold and dry here. Precipitation falls less than 200 mm for the whole year.
Territories where air masses change seasonally twice a year belong to transitional climatic zones. In titles transition zones the prefix “sub” appears, 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.
Thus, the subarctic zone is located between the Arctic and temperate, the subtropical - between the temperate and tropical, the subequatorial - between the tropical and equatorial zones. In transitional zones, the weather is determined by air masses that come from neighboring main zones and change with the seasons. For example, the climate of the subtropical zone in summer is similar to the climate of the tropical zone, and in winter - to the climate of the temperate zone. And the climate of the subequatorial zone in summer has characteristics of an equatorial climate, and in winter - of a tropical climate. In the subarctic zone, the weather in summer is determined by moderate air masses, and in summer by arctic ones.
Thus, climate zones are located zonally and this is due to the influence of solar radiation. Thus, the type of climate on Earth varies zonally. Climate type is understood as a constant set of climate indicators, characteristic of a certain period of time and certain territory. But earth's surface heterogeneous, therefore, within climatic zones they can form Various types climate.
The boundaries of climate 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 climate zone, different types of climate can form. They differ from each other in the amount of precipitation, the seasonality of its distribution and annual amplitudes temperature fluctuations. For example, in the temperate zone of Eurasia there are marine, continental and monsoon climates. Therefore, individual climatic zones are also divided into climatic regions.
Thus, 13 climatic zones are conventionally distinguished on Earth: 7 of them are main and 6 are transitional. The determination of climate zones is based on the air masses that dominate the region throughout the year. Individual 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 climate zone.
Climatic zones are basic and transitional. The main climatic zones have a constant pattern of air movement throughout the year. In transitional areas, signs of two main zones are observed depending on the time of year. The main types include:
1. Equatorial belt
Located on both sides of the equator. Characterized by constant temperature air (24°−26°C warm), temperature fluctuations at sea are less than 1°C. Maximum solar heat is observed in September and March, when the sun is at its zenith. During these months the maximum falls. The annual precipitation is about 3000 mm; in the mountains, precipitation can reach 6000 mm. Precipitation usually occurs in the form of showers. There are many wetlands, dense multi-tiered wetlands with an exceptional diversity of flora and fauna. For most cultivated plants, high moisture is favorable, so in the equatorial zone two harvests are harvested per year.
The equatorial climate zone includes the rainforests of the left tributaries of the Amazon, the Andes of Ecuador and Colombia, the coast of the Gulf of Guinea, Cameroon, the right tributaries of the Congo, the upper Nile, the southern half of the island of Ceylon, most of Indonesian archipelago, parts of the Pacific and Indian oceans.
2. Tropical zone
Tropical climate zones in the Northern and Southern Hemispheres cover areas of year-round high pressure areas. In the tropics, the atmosphere over the continent is different, so the oceanic tropical climate and mainland tropical climate. Oceanic is similar, only different steady winds and less cloudiness. Summers over the oceans are warm, about +25°C, and winters are cool, on average +12°C.
A high pressure area prevails over the land, and rain is rare here. The mainland climate is characterized by very hot summers and cool winters. Daily temperature air can change dramatically. Such changes lead to frequent dust storms.
The lush forests are always warm and humid. There is also a lot of rainfall here. The tropical climate zone includes Africa (Sahara, Angola, Kalahari), Asia (Arabia), North America (Cuba, Mexico), South America (Peru, Bolivia, Chile, Paraguay), and the central part of Australia.
3. Temperate zone
The temperate climate zone is far from homogeneous. It has distinct seasons in contrast to the tropical and equatorial ones. The climate is distinguished by a maritime climate and a humid continental one. All zones differ in average annual precipitation and characteristic vegetation.
Marine dominates in the west of Northern and South America, Eurasia. There are many cyclones here, so the weather is unstable. In addition, the westerly winds blow, bringing all year round precipitation. Summer in this zone is warm, about +26°C, winter is cold, from +7°C to −50°C. Continental predominates in the center of continents. Cyclones penetrate here less frequently, so there are warmer and drier summers and more Cold winter.
4. Polar belt
Forms two belts: Antarctic and Arctic. The polar zone has a unique feature - the sun does not appear here for several months in a row (polar night) and the polar day also lasts a long time, when it does not go beyond the horizon. The air is very cool, the snow does not melt almost all year.
Transition zones include:
1. Subequatorial belt
The northern belt includes: the Isthmus of Panama, Venezuela, Guinea, the Sahel deserts in Africa, India, Myanmar, Bangladesh, South China. The southern belt covers the Amazonian lowland, Brazil, central and eastern Africa, and northern Australia. In summer, equatorial air masses dominate here. There is a lot of rainfall average temperature+30°С. In winter in subequatorial belt Tropical air masses rule, the temperature is about +14°C. The territory of this climatic zone is very favorable for human life; it is here that many civilizations arose.
This zone is dominated by either a Mediterranean or subtropical climate. There is a lot of rainfall almost all year round, so the vegetation is particularly diverse. The subtropical zone covers the Mediterranean, South coast Crimea, Western California, southwestern Africa and Australia, southern Japan, Eastern China, northern New Zealand, Pamir and Tibet.
3. Subpolar climate.
This climate zone is located on the northern outskirts North America and Eurasia. In summer it is cool here (+5°C-10°C), in winter arctic air masses come here, winters are long and cold (up to -50°C).
The air temperature here is constant (+24° -26°C); at sea, temperature fluctuations can be less than 1°. The annual amount of precipitation is up to 3000 mm, and in the mountains of the equatorial belt, precipitation can fall up to 6000 mm. More water falls from the sky than evaporates, so there are many wetlands and dense rain forests - jungles. Remember the adventure films about Indiana Jones - how difficult it is for the main characters to make their way through the dense vegetation of the jungle and escape from the crocodiles who adore muddy waters small forest streams. All this is the equatorial belt. To its climate big influence provided by the trade winds, bringing here abundant precipitation from the ocean.
Northern: Africa (Sahara), Asia (Arabia, southern Iranian Plateau), North America (Mexico, Western Cuba).
Southern: South America (Peru, Bolivia, Northern Chile, Paraguay), Africa (Angola, Kalahari Desert), Australia (central part of the continent).
In the tropics, the state of the atmosphere over the continent (earth) and the ocean is different, therefore a continental tropical climate and an oceanic tropical climate are distinguished.
The oceanic climate is similar to the equatorial climate, but differs from it in less cloudiness and stable winds. Summers over the oceans are warm (+20-27°C), and winters are cool (+10-15°C).
Over the tropical land (mainland tropical climate), a high pressure area prevails, so rain is a rare guest here (from 100 to 250 mm). This type of climate is characterized by very hot summers (up to +40°C) and cool winters (+15°C). The air temperature can change dramatically during the day - up to 40°C! That is, a person can languish from the heat during the day and shiver from the cold at night. Such changes lead to destruction rocks, creating a mass of sand and dust, which is why dust storms are frequent here.
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This type of climate, like the tropical one, forms two zones in the Northern and Southern Hemispheres, which form over areas of temperate latitudes (from 40-45° North and South latitudes to the Arctic Circles).
There are many cyclones in the temperate zone, causing the weather to become capricious and produce either snow or rain. In addition, westerly winds blow here, which bring precipitation all year round. Summers in this climate zone are warm (up to +25°-28°C), winters are cold (from +4°C to -50°C). Annual precipitation ranges from 1000 mm to 3000 mm, and in the center of the continents it is only up to 100 mm.
In the temperate climate zone, unlike the equatorial and tropical ones, the seasons are clearly defined (that is, you can build snowmen in winter and swim in a river in summer).
Temperate climate is also divided into two subtypes - marine and continental.
Marine dominates western parts North America, South America and Eurasia. It is formed by westerly winds blowing from the ocean to the mainland, so there is quite cool summer(+15 -20°С) and warm winter(from +5°C). Precipitation brought by westerly winds falls all year round (from 500 to 1000 mm, in the mountains up to 6000 mm).
Continental predominates in the central regions of the continents. Cyclones penetrate here less frequently, so there are warmer and drier summers (up to +26°C) and colder winters (up to -24°C), and the snow lasts a very long time and melts reluctantly.
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Polar belt
It dominates the territory above 65°-70° latitude in the Northern and Southern Hemispheres, therefore it forms two zones: Arctic and Antarctic. The Polar Belt has a unique feature - the Sun does not appear here at all for several months (polar night) and does not go below the horizon for several months (polar day). Snow and ice reflect more heat than they receive, so the air is very cool and the snow does not melt for most of the year. Since a high pressure area is forming here, there are almost no clouds, the winds are weak, and the air is saturated with small ice needles. The average summer temperature does not exceed 0°C, and in winter it ranges from -20° to -40°C. Rain falls only in the summer in the form of tiny droplets - drizzle.
Between the main climatic zones there are transitional zones, which have the prefix “sub” in their names (translated from Latin as “under”). Here, air masses change seasonally, coming from neighboring belts under the influence of the Earth's rotation.
a) Subequatorial climate. In summer, all climatic zones shift to the north, so equatorial air masses begin to dominate here. They shape the weather: a lot of precipitation (1000-3000 mm), average air temperature +30°C. Even in the spring the sun reaches its zenith and burns mercilessly. In winter, all climatic zones shift to the south, and tropical air masses begin to dominate in the subequatorial zone; winter is cooler than summer (+14°C). There is little precipitation. The soils dry out after summer rains, so in the subequatorial zone, unlike the equatorial zone, there are few swamps. The territory of this climatic zone is favorable for human life, which is why many centers of civilization are located here.
The subequatorial climate forms two zones. The northern ones include: the Isthmus of Panama ( Latin America), Venezuela, Guinea, the Sahel desert belt in Africa, India, Bangladesh, Myanmar, all of Indochina, Southern China, part of Asia. TO southern zone include: the Amazonian lowland, Brazil (South America), central and eastern Africa and the northern coast of Australia.
b) Subtropical climate. Here tropical air masses predominate in summer, and in winter - air masses of temperate latitudes, which determines the weather: hot, dry summers (from +30°C to +50°C) and relatively cold winters with precipitation, and no stable snow cover is formed.
c) Subpolar climate. This climate zone is located only on the northern edges of Eurasia and North America. In summer, humid air masses come here from temperate latitudes, so summers here are cool (from +5°C to +10°C). Despite the small amount of precipitation, evaporation is low, since the angle of incidence of the sun's rays is small and the earth does not warm up well. Therefore, in the subpolar climate in northern Eurasia and North America there are many lakes and swamps. In winter, cold arctic air masses come here, so winters are long and cold, temperatures can drop to -50°C.
On the climate (and, therefore, climate zone) influence and shape it, depending on geographical conditions, climate-forming factors. These include: the amount of radiation from the sun reaching a certain surface of the Earth; atmospheric processes circulation; volumes of biomass. These factors that determine climate can vary significantly depending on the latitude of the area. It is latitude that determines at what angle sunlight falls on the surface of the globe and, accordingly, how intensely the surface located at different distances from the equator will warm up.
The thermal regime of a particular area depends to a large extent on its proximity to the oceans, which act as heat accumulators. On land surfaces bordering the oceans, more mild climate climate zone, compared to the climate in the interior of the continents. Daily and seasonal temperature changes near large volumes of water are more gradual than in a continental climate closer to the center of the continents. There is more rainfall here and the sky is often covered with clouds. Against, continental climate characterized by sharp temperature changes and less precipitation.
A phenomenon associated with the oceans, sea currents are also the most important factor determining the weather on Earth. Carrying warm masses of water around the continents, they warm atmospheric air, bring cyclones with large amounts of precipitation. How radically a current can influence nature can be seen using the example of the North Atlantic Current. In those areas that fall within the zone of its influence, dense forests grow. And in Greenland, located in the same latitudes, there is only a thick layer of ice.
It has no less influence on the climate and topography (which also affects the formation of the climate zone). Everyone knows the footage of climbers climbing mountains, who, starting from green meadows at the foot of the mountain, a few days later stand on snow-capped peaks. This happens due to the fact that with every kilometer above sea level, the ambient temperature drops by 5-6 °C. In addition, mountain systems prevent the movement of both warm and cold air masses. Often the climate on one side and the other of a mountain range can differ significantly. A striking example of this is the difference in air temperature and humidity in Sochi and Stavropol, located on opposite sides of the Caucasus Mountains.
To correctly define the concept " climate zone“We need to distinguish between terms such as weather and climate.
Weather is the state of the troposphere at a certain period of time in a specific area. Climate is considered to be the average established weather pattern. What's happened climate zone, what are its varieties?
Climatic zone and its properties.
Climatic zone It is customary to call the latitudinal band, which differs from other bands in the circulation of the atmosphere, as well as the intensity of heating of the Sun.
There are a total of 7 species on the planet climatic zone c, which in turn are divided into main and transition zones. The category of main belts is also commonly called permanent.
Permanent and transitional climatic zones.
Constant (basic) is called climate zone, in which one air mass dominates throughout the whole year. The main types of zones include: temperate, tropical, equatorial and arctic.
Transition zones are characterized by a change in air masses, that is, it becomes hot in the summer and colder in the winter. There are subarctic, subtropical and subequatorial zones.
Equatorial climate zone.
This subspecies of the main climate zone located in the equator region. This is a one-of-a-kind belt that is divided into several parts. Throughout the year it is influenced by the equatorial air mass.
The main features of the equatorial belt:
- high humidity;
- high precipitation (up to 7 thousand mm per year);
- heat(from 20°C and above).
Natural area of this climate zone Wet forests are considered to be filled with various poisonous plants and animals.
The Amazonian lowland is located in this belt, equatorial Africa, as well as the Greater Sunda Islands.
Subequatorial climate zone.
This subspecies is transitional climate zone located between the equatorial and tropical zones. Consequently, 2 air masses change on its territory during the year.
In the subequatorial belt there are Northern Australia, northern South America, the Hindustan Peninsula, and Southeast Asia.
Tropical and subtropical zones.
The tropical zone is characteristic of tropical latitudes. Weather in the tropics depends on the height of the sun above the horizon. For the tropical climate zone characterized by sharp temperature changes - from hot to cold.
This is considered the main reason why the world of flora and fauna is very poor. This subtype of permanent belts includes North Africa, Mexico and the Caribbean islands.
The subtropical zone is located in the middle of the temperate and tropical zones. It is customary to distinguish between northern and southern subtropical zones. IN summer period tropical heat prevails here, which is characterized by dryness, and in winter there is a cold air mass.
The climate zone characteristic of the Great Chinese Plain, North Africa, North America and southern Japan.
Temperate climate zone.
A distinctive feature of the temperate zone is the ability of temperatures to vary seasonally. For such climate zone negative temperature is typical.
Temperate latitudes contain large parts of Europe, Great Britain, Russia, Canada and the northern United States.
