Genetic classification of climates B.P. Alisova
Climate classification principles
To analyze the patterns of climate formations within the global system and solving practical tasks, it is necessary to know the distribution of climatic values \u200b\u200bon the earth's ball or the area, as well as the climatic complex as a whole.
Depending on the objective of the study, there are various approaches to climate classification. If this is done for the purposes of analyzing the origin of the climate itself or for linking with a complex of natural conditions (landscape-geographical zones), then such a separation of climates is called climate classification , and if for applied purposes (maintenance of agriculture, construction, transport) - climatic zoning .
Climate and zoning classifications are numerous and are determined by various tasks. There are classifications that climb the spread of vegetation, soils, a river network, relief in general or studying the patterns of formation from local climates of the global climate system.
Modern classifications And the zoning is not limited to the division of climates, they also identify their system, thereby paying attention to their similarity.
The basis of the genetic classification of climates is based on the division of the earth's surface on climatic zones and areas in accordance with the conditions for the overall circulation of the atmosphere, expressing in the predominance of the air masses of a certain geographic type, during the year or one of the two main seasons. In addition to seasonality conditions of circulation, two types are distinguished in each zone: the climate is low and the climate of the highland. This gives the basis for linking circulating borders with landscaped.
In real conditions, the situation is more complicated. Circulation processes are determined in low latitudes moisturizing, and thermal conditions differ little, and therefore climate borders on Alice are well coincided with landscaped zones. In moderate latitudes, moisturizing is also determined by atmospheric circulation. When determining climatic boundaries, the removal of various parts of the mainland from the ocean is taken into account.
It is much more complicated by the situation with thermal boundaries in the warm half of the year, which in the wallropic zone strongly depends on the radiation conditions.
The formal boundaries of the propagation of air masses in the conditions of their continuous thermal transformation do not always correspond to landscaped boundaries.
The latitudinal zones and types of climates on Alisa, their features are given in the table. Latitude climatic belts represent the four zones, which prevails some one air mass (EV, TV, WC, AB), and three zones where in the summer they prevail aerial masses Lower, and in winter higher latitudes.
B.P.Alisov allocates seven major climatic (circulating) zones: Equatorial, two tropical, two moderate, arctic and antarctic. Each zone is characterized by a constant predominance of the air masses of the geographic type, the same name with the zone. The intermediate zones are then distinguished: the two zones of equatorial monsoons with a winter predominance of tropical and summer equatorial air, two subtropicals with a winter predominance of polar and summer tropical air, subarctic with a winter predominance of arctic air and summer-air temperate latitudes.
Scheme of latitudinal belts (zones) and climate types (by B.P. Alisa)
From completely different considerations, although not without taking into account the average baric field, built its classification by B.P. Alisov (1936-1952). This classification combines the severity of the physical approach to the formulation of the principles of classification, the simplicity of the submissions used and the visibility of the results obtained.
Alice took important circulating signs as a basis, integrally characterizing the temperature and humidity state of the climate of a certain region. He used as a defining indicator the predominance of certain air masses in different seasons, and the most frequent positions of the main atmospheric fronts (climatic fronts) were taken by the climate borders.
The quantitative characteristics for the position of these fronts does not exist, so that they are tentatively on the synoptic experience.
We give a brief overview of the climate systems of Alice, presented in Table. 6.6.
In each hemisphere, four climatic belts are distinguished on the basis of the predominance in them during the year of one of the main air masses: equatorial, tropical, moderate, arctic (Antarctic).
Between the main belts, three transition belts are distinguished, where, due to seasonal migration, air masses are prevailing lower, and in winter higher latitudes. This is a subequatorial belt, in which the equatorial air prevails in the summer, and in the winter - tropical. In the subtropical belt in the summer the tropical air is dominated, in winter - moderate. In the subartonctic) belt in summer, the air is moderate, in winter - the Arctic (Antarctic). In each of the latitudinal belts, the continental and oceanic climate types are highlighted. In addition, due to the fundamental differences in circulation processes at various borders of the mainland, the types of climate of Eastern and Western coasts of continents are distinguished, including both part of the sushi and part of the adjacent marine water area. Each belt stands out a mountain type of climate.
Table 6.6..
Table 6.6.. System of belts and zones by classification B.P. Alice
Belt 1, 3, 6 are not manifested on all meridians, the first two due to large circulation shifts for the seasons, the latter, on the contrary, due to the lack of a significant seasonal shear of the borders of the air masses in some areas (Fig. 6.2).
Fig. 6.2. Climate classification scheme for bp.p. Alisa
According to the classification of B. P. Alisov in the Equatorial climate, the continental and oceanic climate types are allocated. They do not differ too much among themselves according to the temperature and humidity regime. Above the continent in equatorial latitudes, the air is also very moist for the large moisturizing of the underlying surface and the large evaporation of tropical vegetation. Therefore, it is usually no distinction between the oceanic and continental equatorial climate. In latitudes close to the equator (up to 5-10 ° in each hemisphere), where the inflow of solar radiation changes little during the year, there is a very uniform temperature mode. Both on the sea and on land, the average perennial temperatures of all months of the year from +24 to +28 ° C. Annual temperature amplitude may be no more than 1 ° C and usually does not exceed 5 ° C. Daily amplitudes of the temperature of about 10-15 ° C. Evaporation is large, because the absolute humidity is large. It can exceed 30 g / m 3. Relative humidity is also great. Even in the most dry months of the year it is above 70%.
The precipitation in the Equatorial Type of Climate is abundant, have a storm character and are often accompanied by thunderstorms. Most of them falls in the intrachetic zone of convergence: they are not so intense over the sea and are not so frequent as above the land. In general, 1000-3000 mm precipitation falls over the year. But in a number of places, for example, in the mountainous regions of Indonesia, in Central Africa, more than 6000 mm falls. In most areas, the distribution of precipitation during the year is more or less uniform; On land, these are areas of wet rainforests in South America, Africa, Indonesia. Landscape - wet equatorial forest.
In some parts of the tropical oceans, in particular in Indian and the West of the Pacific Oceans, as well as in South Asia and in the tropics of Africa and South America, the regime of tropical monsoons is dominated.
Together with a more or less sharp seasonal change of prevailing air flows, a tropical air change to equatorial from winter by summer occurs. The air temperature in the tropical monsoon zone above the ocean is just as high and has the same small annual amplitude, as in the equatorial climate. Over the land, the annual amplitude of temperature is greater and grows with geographic latter.
The most prominent feature of this type of climate on continents is a sharp difference between the dry and rainy periods. During the winter in this type of climate, continental tropical air masses with high temperatures and absence of precipitation are dominated. In summer, with the arrival of the summer south-western monsoon, carrying wet equatorial air masses, the rainy period begins, the temperature is somewhat reduced. The amount of precipitation can vary greatly depending on the removal of the point from the ocean, from the latitude, duration of the rainy period, the conditions of the orography, the vertical power of the equatorial air mass and other factors.
Thus, in the type of continental tropical monsoons, the year is sharply divided into dry (winter) and rainy (summer) periods. The annual temperature course discovers the main maximum temperature in the spring, the main minimum - in winter, the secondary maximum - in the fall and secondary minimum - in the summer during the summer monsoon. Due to the long-term dry period, a typical landscape in this type of climate is savanna, turning on the periphery adds to the poles in the steppes and semi-deserts.
In this type, as in continental, there is a seasonal change of air masses. IN winter months It prevails sea tropical air, the properties of which, naturally, are very different from the continental, and above all by temperature and humidity. At the same time, the sea tropical air differs little from the equatorial coming from the summer monsoon. For the type of oceanic monsoons, small as annual (1-2 ° C) and daily (not exceeding 2-3 ° C) air temperature amplitudes are characterized. The average monthly temperatures are 24-28 ° C. The most characteristic feature of the climate is the absence of a dry period in the strict sense of the word and the large duration of the summer rainy period. Northeast Winter Monsoon, but since it carries a wet sea tropical air, then rains fall out during the winter monsoon, but their number is significantly less than during the summer southeast monsoon, which brings a wet equatorial air mass.
It includes Indian and West African monsoons. Summer Monsoon is generally connected with southwestern air currents, winter monsoon - northeast. Especially sharply expressed annual precipitation. In general, we can say, during the domination of the summer monsoon, 75% of the annual amount of precipitation falls. Orography of Western shores on the size and distribution of precipitation. So, in high shores and on the slopes of the mountains addressed to the summer monsoon, the precipitation increases sharply. In the annual temperature during the temperature, the maximum falls on the spring.
The absolute and relative humidity (maximum in summer) and cloudy (sharp maximum in summer and a sharp minimum in winter) also change dramatically. For example, cloudy in Calcutta is 84% \u200b\u200bin July and 8% in January.
Due to the dry winter for the climate of tropical monsoons of Western coast, the landscape of Savannan is especially characteristic. In one of the areas of the tropical monsoon zone, the highest average annual temperatures on the globe are observed. On the southwest banks of the Red Sea, the summer monsoon from the southern hemisphere sometimes falls into Eritrea. Its temperature additionally rises as a result of the foore process, so there are very high air temperatures on the coast of Eritrea. In Massawa (15.6 ° S.Sh., 39,5 °, V.D.) The average temperature of January and February + 25 ÷ + 26 ° C, July +35 ° C, and the average annual + 30 ° C.
The most characteristic distinctive feature of this type from the previous one is the high duration of the rainy period, often with a displacement of the maximum of precipitation at the end of summer and the beginning of autumn and a relatively humid dry period. The air flow of the summer monsoon here is southwestern, southern and even southeast, winter - northeast. The northeastern flow of the winter monsoon before the entry into the mainland has time to go through a sufficiently long way over the water surface of the East-Chinese and South China seas and the Western of the Pacific Ocean, so the winter monsoon is quite wet.
So, in Ho Chi Minh City (Vietnam, 10 ° 49 "S.Sh., 106 ° 40" V.D.) The summer monsoon begins in May (196 mm liquid precipitation) and ends in November (122 mm), and the main maximum rain has to have For September (292 mm), and the secondary maximum is June (285 mm). From 1806 mm of rain falling out for the year, almost 93% falls on a rainy period and 7% - on dry. Maximum temperature drops for April (29 ° C), in the rain period, the temperature drops from 28 ° C in May to 26 ° C in October and then does not change during the dry season.
Landscape - wet equatorial forest.
Tropical climates are formed in areas of predominance of tropical air masses. It is known that the tropical air over the oceans is formed in subtropical anticyclones. Above the continents of the area of \u200b\u200bits formation are the deserts and savanna of a tropical belt. For the tropical belt, high values \u200b\u200bof the radiation balance are characterized: over the oceans, they constitute about 5000 MJ / m 2 · year, and over the continents - 2500 MJ / m 2 · year.
Over the continents in this belt, because of the extreme dryness, the costs of heat for evaporation are small. Therefore, despite the great values \u200b\u200bof efficient radiation and a large albedo, the surface of the continent in the summer is strongly heated and the continental tropical air acquires high temperatures.
This climate is observed in North and South Africa, in Arabia, most of Australia, in Mexico, in the middle part of South America, i.e., in those areas on both sides of the equator, where there is no change of monsoon, where tropical air prevails all year round . These areas are the belts of tropical deserts, which include sugars, the Arabian desert, the deserts of Australia, etc.
Cloudiness and precipitation here are very small, the radiation balance of the earth's surface due to dryness of air and the large albedo of the earth's surface is less than in equatorial belt. However, the air temperature is very high, since there are small heat costs for evaporation. Summer is exclusively roast, the average temperature of the warmest month is not lower than + 26 ° C, and in places almost up to + 40 ° C. It is in the zone of tropical deserts there are the highest high maxima on the globe - about +57 ÷ + 58 ° C. Winter is also warm, with the temperature of the cold month between + 10 ... + 22 ° C.
Daily fluctuations in temperature, sometimes reaching 40 ° C.
The annual amounts of precipitation in most cases are less than 250 mm, and in some places less than 100 mm.
This type of climate is determined by the properties of sea tropical air, which is formed in those latitudes of subtropical anticyclones, to which the intrachetic convergence zone in its seasonal displacement does not reach.
According to the peripheral of subtropical anticyclones addressed to the equator, the steady regime of trade winds with characteristic weather conditions and climate is dominated here.
For oceanic tropical climate Moderately high temperatures, increasing towards the equator, are characteristic. Middle temperatures summer months from + 20 to + 27 ° C. In winter, in high-tech parts, the temperature zone of the Passover are reduced to + 10 ... + 15 ° C. The presence of anti-cyclonic trade in inversion at low height does not give convection to develop in height. Kuch and layered-cumulus clouds arise in large quantities: average cloudiness is about 50% and more. But there are no big precipitation in the trade in the transmission zone, with the exception of those islands where the orographic conditions contribute to them. In the open ocean, the weather in the trade winds zone is predominantly dry, as the clouds do not reach the level of glaciation. Weak precipitation associated with the coagulation of droplets in the clouds do not change significantly this position. Characteristic feature This type of climate is the development of tropical cyclones over the oceans, excluding the southern part of the Atlantic and southeastern part of the Pacific Oceans. In addition, significant precipitation is connected with them in a common extremely dry climate.
It is also called the climate of Western coasts of continents. In the Western coasts of the mainland, the winds of the North Quarter stands in the northern hemisphere and southern quarters in the southern hemisphere prevail during the year. In the zone of the Pattone, the temperature is relatively low, as the air here quickly comes from high latitudes along the eastern periphery of subtropical anticyclones and in addition flows over cold waters of cold ocean flows. The annual amplitude of temperature is small, as above the oceans. The precipitation is very small (less than 100 mm per year) due to low temperatures of water and low-laying trade inversion, but the humidity is high (80-90%) and fogs often occur. This is a climate of coastal deserts, such as the west coast of Sahara, South California, Namib desert (South Africa) and Atakama (South America).
(The climate of the eastern coasts of the mainland). This type of climate is very different from both the climate of the eastern periphery of oceanic anticyclones and the continental tropical climate. Throughout the year on the eastern coasts, the removal of sea tropical air by the winds of the Passats prevails. The trade winds on the western periphery of subtropical anticyclones, passing a long path over the oceans, is enriched with moisture and acquire constituents aimed at poles.
Due to the predominance of sea tropical air in all seasons of the year on the eastern coasts, a warm, wet climate with a large amount of precipitation is formed. The climate of Oriental coasts of tropical latitudes somewhat resembles the equatorial climate, but differs from the latter by large annual amplitudes of the air temperature.
Landscape of coasts - tropical forests.
In subtropical latitudes, i.e., in latitudes of about 25-40 °, climatic conditions are determined by a sharp seasonal change of circulation conditions and, consequently, a sharp change of the predominance of air masses. Summer zone high pressure And the polar fronts are shifted to higher latitudes. At the same time, the subtropics are captured by tropical air from lower latitudes. Due to the displacement of subtropical anticyclones to high latitudes, the pressure in subtropics over the oceans is increased in the summer. It is reduced above the land. In winter, the polar fronts are shifted to low latitudes, and therefore subtropics are captured by moderate air. In this case, cyclonic activity applies to the ocean in the subtropics. Above the mainland, the pressure in the subtropics in the winter is growing on average, since the winter continental anticyclones apply to the subtropical latitudes of cold continents. Hence the seasonal differences in weather mode, and therefore, in the climate of subtropics.
In the summer, subtropics inside the continents are under the influence of blurred areas of reduced pressure, so-called thermal depressions. They are formed by the masses of continental tropical air with high temperature, low moisture content and small relative humidity. The weather here in the summer is clouded, dry and hot. The average temperatures of summer months are close to + 30 ° C or exceed this magnitude. In winter, cyclonic activity is distributed on these areas, as cyclones are often generated or polar fronts pass. The weather is unstable, with sharp change in temperature and precipitation. Annual precipitation no more than 500 mm, and sometimes a lot less. This is the steppes zone, semi-desert and deserts.
The region of the continental subtropical climate includes a large (southern) part of the desert of the Turan lowland, located on the territory Central Asia. Here the moderate air dominates in winter, so winter temperatures are significantly lower than in tropical deserts; In summer, the masses of continental tropical air with a very high temperature, low relative humidity, very low cloudiness and a large dustiness are formed. In Africa and Australia, there are no climates of this type.
A special kind of continental subtropical climate is a climate of high subtropical Nagrai. It is observed at the high mountains of Asia - Tibet and the Pamir, at altitudes 3500-4000 m. The climate is sharply continental, while the summer is relatively cool, and the winter is cold. Precipitation in general is not enough; This is a high desert climate. However, the characteristic signs of the continental subtropical climate - the predominance of temperate temperate air masses, and in the summer of tropical air masses - are stored here.
In the subtropical latitudes of the oceans in the summer, anticyclone regimens with severe and dry weather with weak winds prevail, and in winter - cyclonic activity with rains and strong winds, often with storms. The annual amplitudes of temperature are less than in the continental type, on average about 10 ° C. In the eastern parts of the oceans, summer is relatively cool, as air flows are often penetrated from higher latitudes (on the eastern peripherals of subtropical anticyclones) and cold ocean flows are undergoing. In the western parts of the oceans, summer is warmer. In winter, on the contrary, the cold mass of air from the mainland (Asia, North America) and temperatures are lower here than in the East fall into the western parts of the oceans. In the central parts of the oceans of the northern hemisphere, the average temperatures of summer months in subtropics + 15 ... + 25 ° C, winter months +5 ... + 15 ° C. In the southern hemisphere, winter temperatures above, summer lower, and annual amplitudes are even less.
In the summer, the Western coast of continents in subtropics are on the eastern periphery of subtropical anticyclones or in their springs. Clear and dry weather prevails. In winter, a polar front with cyclonic activity and with precipitation often occurs here. Thus, the summer in the Mediterranean climate is hot enough and dry, winter rainy and soft. It may fall out annually, but without the formation of snow cover. The precipitates are generally not very large. A small amount of precipitation in summer gives the climate character of some dryness. This type of climate is characterized primarily for the area. Mediterranean Sea. The subtropical type of climate applies to Western Transcaucasia. The Mediterranean Climate Type is observed on the coasts of California, Oregon and Washington in North America, on average Chile, in the south of Australia, in the extreme southern Africa (Cape Peninsula).
The Mediterranean climate is characterized by peculiar vegetation, including many drought-resistant species; These are forests and shrubs with a large admixture of evergreen rocks.
In winter, these areas are under the influence of cold northwestern air flows from the mainland; In summer, air from the ocean comes in southeastern flows. The annual movement of precipitation is opposite to the Mediterranean type. In winter, the weather is clear and dry; In summer, on the contrary, abundant precipitation falling in cyclones over the mainland, part of the convective, part of the frontal. Playing a big role and the orographic increase in precipitation on the winding slopes. The precipitation is generally abundant, and therefore the type of climate is characterized by richly developed forests from broad-breeds. The snow falls out, but the snow cover is not held. For example, in Beijing (39.9 ° S.Sh., 116.5 ° V.D.) The average temperature of July +26 ° C, and January -5 ° C; The annual precipitation amount is 612 mm, of which 235 mm falls in July and in December 2 mm.
In the east of North America, in Washington (38.9 ° S.Sh., 77.0 ° C), the average temperature in July +25 ° C, in January +1 ° C; The precipitation falls 1043 mm, of which 110 mm in July and 65 mm in November. This type of climate is observed in South America. Buenos Aires (34.6 ° Yu.Sh., 58.5 ° C) has an average temperature of January +23 ° C, July +10 ° C; Annual precipitation 1008 mm, of which 116 mm in March and 60 mm in July.
In moderate latitudes, there are large seasonal differences in radiation conditions. In summer, the radiation balance of the underlying surface is large and in areas with a small cloudiness approaching the conditions of tropical latitudes, in winter on the continent - negative. Moderate latitudes are characterized by the most intense cyclonic activity on the polar and the Arctic fronts, so the weather mode here is very volatile. In the northern hemisphere there are large differences in circulation conditions on the mainland and oceans, which cause sharply pronounced types of marine and continental climate. In mainly the oceanic southern hemisphere, the continental climate type in moderate latitudes is practically absent.
Extremely significant climate differences exist on the Western and eastern outskirts of the mainland of moderate latitudes. The climate of the Western shores subject to the prevailing effects of sea air masses is transitional from maritime to continental; Often it is called simply sea. On the eastern shores there is a monsoon type of climate, especially in Asia.
This type of climate is available on the mainland of Eurasia and North America. It is characterized by a warm summer and cold winter with a steady snow cover. The annual temperature amplitude is large and grows with the removal of the mainland. Moisturizing conditions change in the direction of both south to north and from west to east.
In the southern part of the moderate latitude of Eurasia in winter prevails the mode of high pressure. On climatological maps it is in these latitudes that the center of the Winter Asian Anticyclone is located. Therefore, winter sediments here are small and declining with the removal of the mainland. Snow cover for this reason is low, and in Transbaikalia, near the center of Anticyclone, reaches insignificant values, despite the very harsh winter. In the summer, in the southern part of the moderate latitude of Eurasia, anticyclones are also not uncommon, contributing to hot and dry weather. Summer precipitation is larger, but they are small due to high evaporation at high summer temperatures, so moisturizing in the southern part of moderate latitudes is insufficient. In general, in the year 200-450 mm of precipitation drops here. As a result, starting from Moldova, through Ukraine, the southern part of the European territory of Russia and further for the Urals, to Mongolia inclusive, the steppes stretch in which there are often arid conditions in the summer.
In higher latitudes moderate belt Eurasia Summer is less roast, but still very warm, winter is more severe (for each longitude), large annual amounts of precipitation (300-600 mm). Continentality also grows from the west to the east (mainly due to lowering the temperatures of the winter): the annual amplitudes of the temperature increase and decrease the precipitation. Snow cover here is higher and lies longer. This is a zone of mixed or deciduous forests. In Moscow (55.8 ° S.Sh., 37.6 ° V.D.) The average temperature of July +18 ° C, January -10 ° C; The annual precipitation amount is 600 mm. In Novosibirsk (55.0 ° S.Sh., 82.9 ° V.D.) in July +19 ° C, in January -19 ° C; precipitation for the year is 425 mm. Maximum precipitation everywhere falls for the summer.
Another north is the Taiga zone, which stretches from Scandinavia to the Pacific Ocean, with the same patterns in climate change from the west to the East, but with greater severity of winter. Summer in the taiga zone is the same roast, as in lower latitudes, but winter is even colder. It is due to the severity of the winter climate in the eastern part of the taiga zone achieves the greatest continentality. Precipitation falls as much as in the deciduous forest zone; Moisturizing generally sufficient, in Western Siberia, leading even to fearing. In Yakutsk (62.0 ° S.Sh., 129.6 ° V.D.) in July +19 ° C, in January -44 ° C; precipitation for the year 190 mm. It is in Yakutia that the continentality of the climate reaches the greatest value. On the mainland, North America discover the same types of the continental climate of moderate latitudes.
The Atlantic and Pacific Oceans occupy large areas in the temperate latitudes of both hemispheres, and the Indian Ocean - in the temperate latitudes of the southern hemisphere. The prevailing Western transfer is expressed above the oceans than above the continents, especially in the southern hemisphere. Wind speeds are greater than above the mainland. In the 40s and 50 latitudes of the southern hemisphere, between the zone of subtropical anticyclones and subnutrctic latitudes, where the centers of deep cyclones are most often passing, the average wind speeds are 10-15 m / s. The temperature distribution over the oceans is more zone than the continents in the same latitudes, and the differences between the winter and summer are less pronounced. Due to the cold summer, the landscape of the tundra is located on the oceanic islands in such low latitudes, in which there are still no tundra on the mainland. So, Tundra is covered by Aleutian and Commander Islands, Falkland Islands, etc.
In the northern hemisphere, Western parts of the oceans in winter are noticeably colder than the eastern due to frequent intrusions of cold air masses from the mainland. Summer the differences are less. Cloudy over the oceans of moderate latitudes are large and precipitated, especially in subogenous latitudes, where the deepest cyclones are observed.
In the western parts of Eurasia and North America in moderate latitudes, the transfer of marine air masses and winter, and in the summer. Therefore, the climate carries a strong imprint of oceanic influences and is sea. It is characterized not very hot summer and soft winter without stable snow cover, sufficient precipitation and more or less uniform seasonal distribution. It determines the landscape of broad forest and meadows. The precipitates increase dramatically on the western slopes of the mountains.
In North America, due to the presence of cascade and rocky mountains, this type of climate is limited to a relatively narrow coastal territory. In Western Europe, it spreads deep into the mainland with a gradual increase in continentality. For example, in Paris (48.8 ° C.Sh., 2.5 ° V.D.) The average temperature of July +18 ° C, and January - +3 ° C; precipitation for the year 613 mm. In Europe, east of Berlin climate becomes continental. Within Russia, this type of climate goes into the continental climate of the temperate latitudes described above. The greatest number The precipitation falls out in this type of climate in Europe on the highlighted slopes of the mountains. Above indicated a large amount of precipitation for Bergen, but at some stations Alps falls over 2500 mm per year.
In the east of Asia, the climate is typically monsoon. Monsons of moderate latitudes are the continuation of the monsoons of tropical and subtropical, expressed very clearly and are observed about the latitude of northern Sakhalin. Thus, a moderate monsonic climate is observed in the Primorsky Territory, in Northeast China, in Northern Japan and Sakhalin. In winter, the mainland's outlet turns out to be on the periphery of the Asian Anticyclone and the transfer of cold air from Eastern Siberia is dominated here, so winter is clouded and dry with significant cold and sharp minimum precipitation. In summer, cyclonic activity with rather abundant precipitation prevails over the East. An example is the data for Khabarovsk (48.5 ° S.Sh., 135.0 ° V.D.), where the average temperature in July +21 ° C, in January -22 ° C and precipitation of 569 mm per year, from which in the winter half of the year (October - March) accounts for only 99 mm. In the northern regions of the Russian Primorye, where the monsoon wind mode is expressed weakly or absent, the winter due to strong cyclonic activities is softer and the distribution of precipitation during the year is uniform.
On the Atlantic Coast of Canada and Newfoundland, the monsoon circulation is expressed weakly or missing. Winters are not as cold as in East Asia, and summer is quite warm
In the subanctic (subnutrctic) belt, the winter prevails arctic (antarctic) air, in summer - air of moderate latitudes. In the subarctic belt distinguish two main types of climate: continental and oceanic. The continental subarctic climate is observed mainly in the Northern Hemisphere, Oceanic - in South.
According to the northern outskirts of Eurasia and North America in latitudes, which can be called subojury, there is a tundra zone. Winter here are long and harsh, summer cold and frost. In Asia in this type of climate, the poles of the Northern Hemisphere cold are located (Verkhoyansk and Oymyakona district). The average temperature of the warmest month is not higher than +10 ... +12 ° C; This is the limit in which trees can grow. Cold summer and defines the landscape of the tundra. The precipitation in the tundra is less than in the taiga zone - less than 300 mm, and in Eastern Siberia, where cyclones are less likely to fall into the tundra zone, even less than 100 mm. Although there is little precipitation, cloudiness is large and days with precipitation a lot; Therefore, they fall out in minor quantities due to small moisture content of air at low temperatures. Maximum precipitation falls for the summer. No matter how small the sediments, but at low temperatures, they exceed evaporation, therefore, excessive overestimation is observed in the tundra and due to permafrost.
Over the oceans of the southern hemisphere south of 60 ° Yu.Sh. Prior to the coast of Antarctica, the subepolar climate is characterized by a very homogeneous temperature distribution in the summer - for the most part of the water area it is close to 0. But in winter, the temperature quickly decreases and reaches the coast of -20 ° C and below.
In these latitudes, cyclone centers are most often passing, so cloudy here is very large; Great and repeatability of precipitation and fogs. Prevailing western winds Near the mainland is replaced by the eastern.
The climate of the Arctic basin is primarily determined by the disadvantage or complete absence of solar radiation in winter and a very large influx of radiation in the summer. The annual radiation balance of the surface of the Arctic seas is generally positive; Negative balance only on Plateau Greenland. Nevertheless, summer temperatures are low, because radiation is spent on the melting of snow and ice, and the surface temperature and air remain close to 0. The effect of radiation conditions is joined by a strong impact of general circulation of the atmosphere. In the Arctic basin, intensive cyclonic activity is observed in all seasons of the year. Cyclones arise on the Arctic fronts, and also penetrate the Arctic of lower latitudes, where they develop on the polar fronts. Increased pressure prevails all year over High Greenland Plateau. But in the rest of the Arctic, the division changes from month to month significantly, and anticyclonic systems are detected on average maps on relatively small squares in different parts Ocean, and in winter even over Alaska and over the northeast of Asia. Cloudy in the Arctic basin generally big and winds are stronger. Average monthly temperatures in the Arctic basin from -40 ° in winter to 0 ° C in the summer.
Several areas are distinguished:
The most warm Atlantic and European region of the Arctic, where in the process of cyclonic activity there are deep removal of warm atlantic air into high latitudes, especially in winter temperatures.
In the Asian (Eastosibirsk), Canadian and Pacific areas of the Arctic, the Winter is much colder than in the Atlantic European region, but the summer is generally the same. At Cape Shalamurova (73.0 ° S.Sh., 143.3 V.D.) in July +3 ° C, in February -31 ° C, the average annual -15 ° C; precipitation for the year 140 mm.
In the center of the Arctic pool, the average temperatures from -40 ° in winter to 0 ° C in the summer.
Greenland with its high height above sea level and the prevailing anticyclonic regime has a particularly severe continental climate. At the plateau, at the station Icemitte (70.9 ° S.Sh., 40.6 ° zd, 3300 m), the average temperature of July -14 ° C, January -49 ° C, annual -32 ° C.
The climate of the icy continent is the most severe on the globe. The average annual temperatures are reduced here from -10 ° C on the coast, on the latitude of the polar circle, to -50 ... -60 ° C in the central regions of the mainland. The average annual precipitation for the whole mainland is about 120 mm; From the coast inside the mainland, the precipitation is strongly desired.
The main role in the severity and dryness of the Antarctica climate is played by the snow surface of the continent, a large height of it above sea level (on average about 3000 m, and in the center of East Antarctica to 3500 m or more) and the predominant anticyclonic circulation regime. Despite the very large summer inflow of solar radiation, a high albedo of a snowy surface and effective radiation leads to the fact that the annual radiation balance is negative on all the mainland. Negative radiation balance is replenished with the influx of heat from the atmosphere. Cyclonic activity in the southern hemisphere is intensively deployed over the ocean around Antarctica. But on the mainland of Antarctica, cyclones penetrate mainly in the western part of the mainland. In Eastern Antarctica, cyclones penetrate very rarely. Thus, the high pressure mode turns out to be unconditionally predominant. The coast of Antarctica is a zone with a moderately humid and relatively mild climate. Summer here maximum temperatures Sometimes they rise above the zero and intensively melts snow. Especially characteristic of very many areas of the coast. Strong Stock Winds with a high-plateau of the mainland. Together with cyclones, passing near the mainland, Stock Winds lead to the fact that even the average wind speeds in a number of coast places reach 15-20 m / s. The precipitation on the coast of Eastern Antarctica is 400-500 mm, Western - 600-700 mm.
On the glacier slope, in the zone of 600-800 km width (in Eastern Antarctica), strong stock winds are also observed, creating a snowmail transfer of snow. Average monthly wind speeds are 8-13 m / s. Cloudy is small, but still on this zone often spreads the effect of cyclones passing through the ocean or penetrating into the mainland. Therefore, snowfall and blizzards here more often than inside the mainland, but at the bottom of the slope even more often than on the coast.
At the station Pionerskaya (69.7 ° Yu.Sh., 95.5 ° V.D., 2700 m) The average temperature of August -48 ° C, December and January -23 ° C, the average annual -38 ° C; Annual precipitation amount 848 mm
On a high internal plateau of Eastern Antarctica with its mainly anti-cyclonic mode, the average wind speeds decrease to 3-4 m / s. Here, the powerful surface inversion is constantly maintained above the snow surface and exceptionally low surface temperatures are observed, almost to -90 ° C. The average temperatures of winter months about -70 ° C, summer about -30 ° C. Even in the summer, the maximum temperatures below -20 ° C. Clear weather prevails; The precipitation is very small, about 30-50 mm per year. From a third to half of precipitation is created by deposits of frosting from ice clouds on a snow cover. The moisture content in the inner areas of Anthrakdic is very small.
Under the same latoms in Eastern Antarctica are much colder than in Western; In the intramatic regions almost 30 ° C. This is due not only to the heights of the terrain, but also the fact that Western Antarctica is relatively often visited by cyclones that make warm sea air to the mainland.
For the climate of the Plateau of East Antarctica, the East station is characterized (72.1 ° Yu.Sh., 96.6 ° V.D., 3420 m), where the average temperature of August -68 ° C, December -33 ° C, the average annual -55 ° С, absolute minimum -88 ° C. Precipitation for the year about 40 mm.
On the Southern Pole, closest to the Ocean and more prone cyclonic activities (Station Amundsen-Scott, 2880 m), the climate is somewhat softer: average temperatures in August and September -59 ° C, in January -28 ° C, for the year -49 ° С. The annual precipitation amount is 55 mm.
Classification of climates Alice. The genetic classification of climates, which is based on the division of the earth's surface on climatic zones and areas in accordance with the conditions for general circulation of the atmosphere, expressing in the predominance of the air masses of a certain geographic type - all year round or one of the two main seasons. The boundaries between zones are scheduled mainly on the position of climatological fronts in winter and summer. 7 main climatic (circulating) zones are distinguished: Equatorial, two tropical, two moderate, arctic and antarctic. Each of them is characterized by a constant predominance of the air masses of the geographic type, the same name with the zone. The intermediate zones are then distinguished: the two zones of equatorial monsoons with a winter predominance of tropical and summer equatorial air, two subtropicals with a winter predominance of polar and summer tropical air, subarctic with a winter predominance of arctic air and summer-air temperate latitudes. Climate subtypes are highlighted in tropical and subtropical zones: continental, oceanic, eastern periphery of oceanic anticyclones, western periphery of oceanic anticyclones; in moderate zone - subtypes Continental, oceanic, western coasts, oriental coasts (monsonic); in Subarctic I. arctic zones - Continental and oceanic subtypes.
Cepping climates classification. Climate classification based on temperature and precipitation mode. 5 types of climatic zones are planned, it is: a - a wet tropical zone without winter; In - two dry zones, one in each hemisphere; C - two moderately warm zones without regular snow cover; D - two boreal climate zones on the mainland with sharply pronounced borders in winter and summer; E - two polar areas of the snow climate. The boundaries between zones are carried out according to certain isotherms of the coldest and warm months and at the ratio of the average annual temperature and the annual amount of precipitation. annual stroke precipitation. Inside zones of types A, C and D, climates are distinguished with dry winter (W), dry summer (S) and evenly wet (F). Dry climates in the ratio of precipitation and temperature are divided into steppes (BS) climates and the climates of the desert (BW), polar climates - climate tundra (EF) climate and the climate of the eternal (permanent) frost (EF).
Thus, it turns out 11 main climates: AF - Tropical Forest Climate, AW - Climate Savannan, BS - Climate Stete, BW - Climate Desert, CW - Climate Moderately warm with dry winter, CS - Climate Moderately warm with dry summer (Mediterranean) , Ci - the climate is moderately warm with uniform moisture, DW - the climate is moderately cold with dry winter, DF - the climate is moderately cold with uniform moisture, it is a climate of the tundra, EF - the climate of the Eternal Frost. For further detail, 23 additional features and the corresponding indices (A, B, C, D, etc.) are introduced, based on the details in temperature and precipitation mode. Many types of climates according to K.K. K. K. K. are known under the names associated with the characteristic of this type of vegetation.
The basis of the genetic classification of climates B.P. Alice is the geographical types of air masses and their circulation. The separation of land on climatic belts is associated with the conditions for forming climates, which are determined by the circulation of air masses.
In each hemisphere, four main climatic belts are highlighted:
- 1) Equatorial air,
- 2) tropical air,
- 3) air temperate latitudes,
- 4) Arctic (Antarctic) air
In each belt, continental and sea subtypes of air masses and climates are formed under the influence of sushi and the sea. The total system of B. P. Alisova includes the following climates:
I. Hot climates
1.1 Equatorial climate Hot and uniform wet. He is peculiar to inner Amazonia, the Congo Basin (Zaire) and the coast of the Gulf of Guinea, the Malacca Peninsula, the Sunda Islands and the island of New Guinea.
The main climate-forming processes include radiation balance (residual heat). On the continent, it ranges from 2510 to 4190 MJ / m 2 (60-100 kcal / cm 2) per year, on oceans - from 4190 to 5010 MJ / m 2 (100-120 kcal / cm 2) per year. It is less than in tropical latitudes. Almost no seasonal fluctuations in solar radiation. Much more than the residual radiation, the air heats the hidden heat of the vaporization - to 4190-5850 MJ / m 2 (100-140 kcal / cm 2) per year. This heat source supports a uniform temperature of the temperature during the year and day.
The circulation of the atmosphere in the equatorial belt consists of two links: 1) convergence of trade winds and 2) ascending currents (vertical convection).
The interaction of the air mass of tropical and equatorial zones determines the nature of moisture rotation: steam comes from two huge tropical zones and condensed in rising currents in a relatively narrow anti-essential band. Naturally, it falls large here, on average about 2000 mm, the amount of precipitation. Air humidity in the equatorial climate ranges from 81 to 85%, and the annual precipitation amount is about 2414 mm (Singapore).
1.2 Tropical climate. A typical tropical climate is hot and dry, deserted. Variations of the interaction of the "Ocean - atmosphere - Mainland" system cause a sharply pronounced Western-East dissimmetry of the tropical nature of the zone.
The following variations of the tropical climate are distinguished:
- 1) typical desert climates are characteristic of central mainland regions;
- 2) sea variety a deserted climate inherent in the western banks of the mainland;
- 3) Wet tropical forest and savanna climates inherent in the eastern coasts of the mainland.
Solar radiation within the tropical climate is very significant: on the mainland 7530-8380 MJ / m 2 per year, on the oceans - 6,800 MJ / m 2 (160 kcal / cm 2) per year. Radiation balance on land is lower than on oceans - 2510 MJ / m 2 (60 kcal / cm 2) per year. This is due to the fact that 70% and more radiation heat is spent on the heating of the sands of the desert and then due to the high albedo of the sands and the cloudless sky, it is emotionally radiated outside the land. The main battery of thermal energy - water is missing here. The desert is the field of cooling the atmosphere and the geographic shell.
Characterized anticyclonal atmospheric circulation. The lowered air masses are adiabatically heated and drained. High atmospheric pressure and radial spreading of air prevent the penetration of air masses from the ocean into the Western and central sectors. The "Ocean - atmosphere - Mainland" system works not to favor these sectors of the mainland. Typical features of a tropical climate - heat, a large amplitude of temperature and dryness. Large areas are contternated with an uppermost area of \u200b\u200bJuly 30 ° C, sometimes the middle July temperature rises to 36.3 ° (Barbara) and even 39 0 s (in the death valley). In winter, the temperature is 10-20 ° C. The average annual amplitude is about 20 ° C. It is much more daily, it can reach 40 ° C in the air and 80 ° C on the sand surface. On the plains, the temperature sometimes drops to - 5 ° C, and in the mountains of Tibesta to - 18 ° C. The precipitation is not only a little, but they fall far away every year, often they do not happen for several years in a row.
The climate of the western outskirts of the mainland (sea variety of deserted climate) is due to cold currents, inverse air stratification and the transmission circulation, carrying water vapor from the mainland into the ocean.
In the eastern regions of the mainlands of tropical belts - on the banks of the Caribbean Sea, in East Industan, in the Rio de Janeiro area, in Southeast Africa and East Australia - the climate is wet tropical. The sea air masses of the Passops come here, and the precipitation falls a significant amount. In Rio de Janeiro, the annual precipitation is approximately 1099 mm and rains go in every month.
The air temperature above in Rio de Janeiro in January is 25.8 ° C, in July 20.4 ° C.
1.3 subequatorial (subequatorial monsoon, or savanna) climate
The sub-screen climate is composed of two independent climatic regimes: Equatorial in the July part of the year in the northern hemisphere and tropical in opposite seasons. Therefore, the most characteristic of his feature is a sharp separation for two seasons: the rainy season and the dry season. Air humidity in the subequatorial climate is 70 and 87%, the annual precipitation amount is 1880 mm.
The duration of the dry period in the subequatorial belt ranges from one month at the border with an equatorial climate to 11 months at the border with tropical deserts.
II. Subtropical climates
Subtropical climates are between 25 and 40 ° C.Sh. and Yu.Sh., in the belt of subtropical circulation variable. It is characterized by a change of climate regime for the seasons: in summer, the tropical air with high atmospheric pressure dominates and is dry weather, and in winter, temperate low pressure and medium-European weather is spreading to these latitudes.
South (in the northern hemisphere) The border of subtropical latitudes is denoted by the southern limit of winter propagation of temperate air masses or the January position of the moderate front. The northern border of subtropics passes along the northern limit of the Tula position of tropical air, or a tropical maximum, or, finally, on the July position of the moderate front. Subtropics, thereof, can not be considered a strip of gradual transition from moderate climates to tropical. It is latitude with a seasonal change of moderate and tropical air characteristic only for them.
The total solar radiation in the subtropics is 7510--5850 MJ / M 2 (180--140 kcal / cm 2) per year, that is, close to the average for the whole land. There is no excess heat, as in a hot belt, but there is no negative winter balance, as in moderate. Actual temperatures Correspond to solar.
The circulation of the atmosphere in winter is predominantly cyclopic, relatively cold air masses from moderate latitudes are often penetrated.
The moisture turnover is characterized by sharply pronounced seasonality: the sediments fall in winter, the summer is dry (except for monsoon).
In the subtropical belt of the northern hemisphere begins the greatest long-term strike of the mainland; It causes long-term differentiation of the climatic belt. Three regions are formed: Western, Central and East.
Western regions of the subtropical zone are characterized by the Mediterranean climate - Atlas, Southern Europe, anterior Asia, San Francisco, Santiago, Cape Town and Southwestern Australia, South Coast of Crimea, the Black Sea coast near the city of Tuapse (Russia).
For intramatic areas - East Turkey, Iran, South of Central Asia, Gobi, South of the US Middle West, Steppe Argentina - the climate of dry subtropics is characterized. From the Mediterranean, it is characterized by an increase in arid and continentality.
On the eastern outskirts of the mainland - in average China and in the south-east of the United States - subtropics wet. Close to them climate la fees. At all months, rains fall: in winter, due to cyclonic air circulation on a temperate front (under the monsoon conditions with sushi), in the summer of the sea monsoon.
III. Moderate climates
The southern boundary of the temperate climatic belt passes through the summer limit of a tropical maximum, about 40 ° C.Sh. and Yu.Sh. The northern border coincides with the winter position of the Arctic Front, approximately with the southern border of the tundra, near the polar circles.
In a temperate belt, Europe, except for the Mediterranean Peninsulas, Asia north of the Kara-Bogaz-goal line is the middle of the island of Honsu and to the Tundrov Zone, North America from the parallel of the mouth of Missouri to the latitude of the middle of Hudson Bay. IN southern Hemisphere In moderate climate there are only south of South America and the South Island of New Zealand.
Constrictly by the characteristic of the northern moderate belt.
Radiation balance in the moderate belt is reduced to 1257 and 837 MJ / m 2 (30 and 20 kcal / cm 2) per year. The seasonal difference of the radiation regime is very significant: in the summer the balance of about 251 MJ / m 2 (6 kcal / cm 2) per month, a little less tropical, and in the winter it is negative, about 41.9 MJ / m 2 (1 kcal / cm2) per month . In winter, temperate belt does not cost its radiation heat; The advection of heat from tropical latitudes is played. The heat is transferred to the atmosphere and hydrosphere. The bulk of it enters the ocean and peripheral territory, central regions Get out.
In the circulation of the atmosphere, the main thing is the western transfer of air masses, cyclonic and anticyclonic activity and the invasion of the average latitude of both arctic and tropical air. All three air masses are moderate, arctic and tropical - there are continental and marine.
With a drop in radiation heat in a moderate belt, evaporation and total amount of moisture rotation are reduced. On the larger area of \u200b\u200bthe moderate belt drops 500-400 mm of precipitation, their territorial distribution is characterized by a consistent decrease in sushi deep into. In the inner areas, which make up most of the belt, snow falls out and a snow cover persistent to six months is formed.
The following climates are allocated in the northern moderate belt:
- 1. Sea, or Western European, or deciduous forests, or finally the climate of oak. It is characteristic of Western Europe, the coastal strip of North-West America from Alaska to San Francisco and for the south of Chile.
- 2. Mainland, or taiga climate. It is formed in Eurasia from Sweden to Yenisei, in America - in the forest continental states of Canada and the United States.
- 3. For Yeniseem, in Eastern Siberia, the only province of a sharply continental moderate climate is formed on earth. The advection of heat and moisture from the ocean here is the smallest due to the vast sizes of Eurasia. The mainland in winter is getting out, a negative temperature anomaly is formed to - 22 ° C and a powerful thermal anticyclone is created. There is a cloudless clear slightly snowy winter with frosts up to - 64 ° C. The huge area is contaminated by the heater of January in - 30, - 36 and even - 40 ° C. Precipitation is less than 200 mm; Snow cover is thin, the soil is deeply freezing, the eternal Merzlot has a power of 70 to 800 m.
- 4. Arid moderate climate is formed within the northern mainland in Eurasia to the south, and in America west of the forest area. The climate here gradually changes towards aridness, the forests are replaced by steppes, semi-deserts and deserts.
- 5. Missual climate of moderate latitudes, or Far Eastern forests, is typically expressed on the eastern periphery of Asia.
IV. Cold climates
Cold, or subarctic (subnatrotic), or tundra, is called the climate of the circulation variable, at which moderate air dominates in the summer, and in the winter, arctic. Cold climate breaks into two varieties: mainland and sea. I.
- 1. Subarctic mainland tundra climate is inherent in large areas of the Polar Occaras of Eurasia and North America. The southern border of this belt passes 68 ° C.Sh., that is, in isotherm 10 ° C, and with the climate of the ice zone - according to isotherm 00cs of the warmest month. The landscaped borders of the subarctic belt coincide with the limits of the tundra. Residual solar radiation in the tundra zone in the annual output is positive, from 209 to 419 MJ / m2 (from 5 to 10 kcal / cm2) per year. But this is only due to two or three year old; Most of the year the balance is negative. Circulation of the atmosphere In addition to the already known movements of arctic and moderate air lies also in the monsoon trend: the winds dominate with sushi in winter, the winds of the northern directions prevail. This reduces the temperature. The heat regime is supported by the advection of heat atmosphere and hydrosphere, especially in Western regions. Summer is a short and cool, smugmer period less than 90 days, the winter is long and cold: the temperature of January is from - 6 ° in the Murmansk coast until - 400c at the mouth of the Lena. The precipitation is a bit: from 300 mm in the west to 100 mm in Eastern Siberia. But evaporation is even less. Atmospheric moisturizing excess. The soil is covered by eternal Merzlot.
- 2. Oceanic tundra climate is inherent in the islands: Commander and Aleutian in the northern hemisphere, Kergelen, South Orkney, South Georgia and Falkland in South. The oceanic tundra climate on the islands applies to 500 s. sh. and Yu.Sh. This is due to cold currents. Climate Smooth: Winter is warm, about - 3, - 40c, summer is cool, below 10 ° C. Precipitation many, 400 mm; large, up to 80-90%, cloudiness at all months; Family fog, air raw, many days with rain, almost always windy.
V. Climates of the Eternal Frost
Arctic and antarctic climates are allocated. The main climatic processes in ice zones are essential than in moderate. In winter, there is no solar illumination at all, and in the summer it is around the clock. The snowy surface has a high albedo and acts on the troposphere coolingly.
In the summer, within 1-2 months, the balance of the sun is positive, 20.9-41.9 MJ / m 2 (0-1.0 kcal / cm 2) per month. The remaining 10-11 months earth only emits. Solar heat deficiency up to 3350 MJ / m 2 (80 kcal / cm 2) per year. With such radiation balance, the main source of atmospheric heat is the circulation of the atmosphere and hydrosphere. It delivers 3350 - MJ / M 2 (80-100 kcal / cm 2) per year. The air in the climates of the eternal frost is usually warmer than the underlying snow surface. In Antarctica, for example, the air temperature near the snow drops to - 90 0 S.
The conditions of heat adevection in the Arctic and Antarctic are different. In the Arctic, the troposphere receives from water directly and through the sea ice about 167 MJ / m 2 (4 kcal / cm 2) per year, Antarctic is deprived of this heat.
In summer, the average air temperature in the Arctic is about 0 ° C, and on the coasts it reaches 5 ° C, in Antarctica - around - 30 °, - 35 ° C.
In January, in the central Arctic - 40 0 \u200b\u200bs, on the coast of the mainland 30 ° C, and at the ingredic islands, the temperature rises to - 16 ° C (Svalbard). And only over Greenland, the steady anticyclone lowers the temperature of July to - 14 °, and January to - 49 ° C.
Antarctica climate is the coldest on the whole earth. In Eastern Antarctica, at the station East, the temperature of January (summer) - 32 °, August (winter) -71 ° C. On the coast, somewhat softer: in peace in January - 2 °. In August - 18 ° C.
The described zonal climates are characteristic of lowlands, elevations and a low plateau. In the mountains, climatic conditions change with a height, forming a vertical explanation.
Climatic belts are solid or intermittent areas, which are located parallel to the latitudes of the planet. Among themselves, they differ in circulation of air flow and the amount of solar energy. The terrain, proximity to or is also important climate-forming factors.
According to the classification of the Soviet climatologist B. P. Alisov, there are seven main types of climate of the Earth: Equatorial, two tropical, two moderate and two polar (one in and hemispheres). In addition, Alisov highlighted six intermediate belts, three in each hemisphere: two subequatorial, two subtropical, as well as subarctic and subanctic.
Arctic and Antarctic climatic belt
Arctic and Antarctic climatic belt on 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 protracted harsh winters. The maximum summer temperature is + 5 ° C. Arctic ice affect the climate of the land as a whole, not letting it overheat.
Antarctic belt is located in the south of the planet. Under its influence is the nearby islands. On the mainland there is a pole of cold, so winter temperatures are on average - 60 ° C. Summer indicators are not raised above -20 ° C. The territory is located in the area of \u200b\u200bthe Arctic desert. The mainland is almost completely covered with ice. Sushi plots are found only in the coastal zone.
Subarctic and subnutrctic climatic belt
Subarctic and subnutrctic climatic belt on world map
The subarctic zone includes Northern Canada, South of Greenland, Alaska, North Scandinavia, the northern regions of Siberia and the Far East. The average temperature of the winter temperature is -30 ° C. With the arrival of a short summer, the mark rises to + 20 ° C. In the north of this climatic belt dominates, which is characterized by high humidity, wetting and frequent winds. South is located in the Zone of Fundra. The soil has time to warm up for the summer, so shrubs and palpal shrubs grow here.
Within the South Ocean Islands near Antarctica. The zone is susceptible to the seasonal influence of air masses. In winter, the Arctic air dominates here, and in the summer they come from a moderate belt. The average temperature in winter is -15 ° C. On the islands often storms, fogs and snowfalls. In the cold season, the entire water area is engaged in ice, but with the onset of summer they melt. Warm month indicators on average are -2 ° C. The climate is difficult to call a favorable. Vegetable world represented by algae, lichen, moss and dispersion.
Moderate climatic belt
Moderate climatic belt on world map
In the zone of the moderate belt lies a quarter of the entire surface of the planet: North America, and. Its main feature is the clear severity of the seasons of the year. The predominant air masses give high humidity and low pressure. The average temperature of winter temperatures is 0 ° C. In the summer, the mark rises above fifteen degrees. The cyclones dominating in the northern part of the zone provoke snow and rains. Most of the precipitation falls in the form of a summer rain.
District territories are drought by droughts. represented by alternating forests and arid regions. In the north grows, the vegetable world of which is adapted to low temperatures and high humidity. Gradually, it replaces the zone of mixed wide forests. The steppe strip in the south is moving all the continents. The semi-desert zone and the desert covers the western part of North America and Asia.
Moderate climate is divided into the following subtypes:
- nautical;
- moderate continental;
- sharply continental;
- monsoon.
Subtropical climatic belt
Subtropical climatic belt on world map
In the zone of subtropics there is a part of the Black Sea coast, southwest and, south of northern and. In winter, the territory is under the influence of air moving from a moderate belt. The thermometer mark is rarely lowered below zero. In the summer, subtropical cyclones affect the climatic zone, which are well warmed by the Earth. In the eastern part of the mainland moist air dominates. Here is a long summer and soft winter without frost. Western coasts are characterized by arid summer and warm winter.
In the inner areas of the climatic zone of temperature is significantly higher. It is almost always worth clear weather. Most precipitation falls in a cold period when air masses are shifted to the side. Anticious forests with an undergrowth of evergreen shrubs grow on the coasts. In the northern hemisphere, the zone of subtropical steppes comes to a shift, smoothly flowing into the desert. In the southern hemisphere, the steppes go into broad and leaf falling forests. Mountain areas represented by woodlong zones.
In the subtropical climatic zone, the following climate subtypes are distinguished:
- subtropical oceanic climate and Mediterranean climate;
- subtropical intocontinental climate;
- subtropical monsonic climate;
- climate of high subtropical Nagrai.
Tropical climatic belt
Tropical climatic belt on world map
Tropical climatic belt covers separate territories at all except Antarctica. All year round over the oceans dominates the area of \u200b\u200bhigh pressure. Because of this, there is little precipitation in the climatic zone. Summer temperature indicators in both hemispheres exceed + 35 ° C. Medium winter temperatures are + 10 ° C. The average daily temperature fluctuate is felt in the depths of the continents.
Most of the time there is a clear arid weather. The bulk of sediments falls on the winter months. Significant temperature differences provoke dust storms. On the coasts, the climate is significantly softer: winter is warm, and the summer is soft and wet. Strong winds There are practically absent, precipitation falls out the calendar summer. The dominant natural zones are rainforests, deserts and semi-deserts.
Tropical climatic belt includes the following climate subtypes:
- trade house climate;
- tropical dry climate;
- tropical monsoon climate;
- monsonic climate on tropical plateau.
Sub-screen climatic belt
Sub-screening climatic belt on world map
Sub-screen climatic belt affects both hemispheres of land. IN summer time The zone is influenced by equatorial wet winds. In winter, the trade winds dominate. The average annual temperature is + 28 ° C. Daily temperature differences are insignificant. Most of the precipitation falls in the warm season under the influence of summer monsoon. The closer to the equator, the rain is rude. In the summer, most rivers come out of the banks, and for the winter they completely dry.
The plant world is represented by monsoon mixed forests, and palpal. The foliage in the trees turns yellow and falls in the period of drought. With the arrival of the rain it is restored. On open spaces, the savannahs grow cereals and dispersion. The plant world adjusted under rain periods and drought. Some remote forest arrays have not yet been studied by a person.
Equatorial climatic belt
Equatorial climatic belt on world map
The belt is located on both sides of the equator. A constant stream of solar radiation forms a hot climate. On weather conditions, air masses coming from the equator are affected. The difference between winter and summer temperatures is only 3 ° C. Unlike other climatic belts, the equatorial climate remains almost unchanged all year. The temperature indicators are not lowered below + 27 ° C. Because of the abundant precipitation, high humidity, fogs and clouds are formed. Strong winds are practically absent, which positively affects the plant world.
