home Treatment and prevention The climate is continental. Climate continental tropical

The climate is continental. Climate continental tropical

Russian climatologist Vladimir Koeppen defined a humid continental climate as a climate region characterized by large differences in seasonal temperatures. According to Köppen's 1900 definition, areas with a humid continental climate experience warm, hot summers that are often wet, as well as sometimes very cold winters. In addition, precipitation in such climatic regions is usually evenly distributed throughout the year. The coolest month has average temperatures of around -3ºC, while at least four months have average temperatures of 10ºC or higher. However, an area experiencing a humid continental climate should not be arid or semi-arid. According to the Köppen system, humid continental climates are divided into subtypes Dfa, Dfb, Dwa and Dwb, which are also called semi-boreal.

Designation of humid continental climate

The climate regime, which is defined by the average climatological characteristics over 30 years, uses a three-letter code. The first letter code always begins with a capital letter D. The next capital letter: f - does not correspond to any of the classifications; s - dry summer; and w - dry winter. The last letter: a - means the warmest month, the average values of which are above 22º C; b - does not meet the requirements of “a”, but characterizes four months above 10º C.

Areas that experience a humid continental climate

Humid continental climates occur somewhere between 30º and 60º north latitude in northeastern and central Asia, Europe and North America. Since the Southern Hemisphere has a larger oceanic area, as well as greater marine moderation, as a consequence, humid continental climates are virtually non-existent in this region. Thus, humid continental climate together with continental subarctic climate are phenomena that are mainly experienced by regions of the Northern Hemisphere.

The humid continental climates of places such as Nova Scotia, Newfoundland and Scandinavia are heavily influenced by marine influences, while experiencing frosty winters and relatively cool summers. The American Midwest and Southern Siberia have a more extreme humid continental climate, experiencing very cold winters and hotter summer highs compared to maritime regions. Areas such as Milwaukee, Wisconsin have a humid continental climate characterized by both a strong subarctic and subtropical air mass, but are primarily seasonal. For example, cold winters or hot and humid summers.

Precipitation in humid continental climates

Precipitation in humid continental climates comes from either frontal cyclones or convective showers that occur when tropical maritime air moves north behind a retreating polar front. Before such connecting activity a large number of regions experience a special maximum precipitation in summer. However, it is not uncommon to find more uniform patterns. Early summer events include strong tornadoes and thunderstorms, especially when the polar front is at the southern edge of the area. On the other hand, winter precipitation mainly occurs in snow form, with one to four months of continuous snow cover in most regions, especially in the north. Most often, snow begins to fall in combination with strong winds emanating from a severe frontal cyclone, resulting in a blizzard.

Vegetation in humid continental climates

By definition, the type of vegetation that thrives in humid continental climates is forests. that are well adapted to this type of climate regime include coniferous, deciduous, temperate, temperate evergreen forests and temperate grasslands. In the wetter areas of humid continental climates, vegetation such as fir, spruce, oak and pine is present, and many deciduous tree species lose their leaves during the fall season.

Continental climate, a set of climate properties determined by the influence of large land areas on the atmosphere and climate-forming processes. The main differences in the climate of continents and oceans are due to the peculiarities of their accumulation of heat. The surfaces of the continents heat up quickly and strongly during the day and summer and cool down at night and in winter. Over the oceans, this process is slowed down, since water masses during warm times of the day and year accumulate a large amount of heat in deep layers, which is gradually returned to the atmosphere in cold times. Therefore, air temperature and other climate characteristics change (from day to night and from summer to winter) over the continents more than over the oceans (see Continental climate, Marine climate) . Moving air masses leads to the spread of the influence of the oceans on the climate of adjacent parts of the continents and to the reverse influence of the continents on the climate of the oceans. Thus, the climate may be more or less continental (or oceanic), which can be expressed quantitatively; Most often, air temperature is considered as a function of the annual amplitude of air temperature.

In extratropical latitudes, non-periodic changes in air temperature are so frequent and significant that the daily temperature variation is clearly manifested only during periods of relatively stable, low-cloudy anticyclonic weather. The rest of the time it is obscured by non-periodic changes, which can be very intense.
For example, cold snaps in winter, when the temperature at any time of the day can drop (in continental conditions) by 10-20 ° C within one hour.

In tropical latitudes, non-periodic temperature changes are less significant and do not disrupt the daily temperature cycle as much.

Non-periodic temperature changes are associated mainly with the advection of air masses from other regions of the Earth. Particularly significant cold snaps (sometimes called cold waves) occur in temperate latitudes due to the intrusion of cold air masses from the Arctic and
Antarctica. In Europe, severe winter cold snaps also occur when cold air masses penetrate from the east, and in Western Europe - from the European territory of Russia. Cold air masses sometimes penetrate into
Mediterranean basin and even reach North Africa and Western Asia.
But more often they linger in front of European mountain ranges located in the latitudinal direction, especially in front of the Alps and the Caucasus. That's why climatic conditions The Mediterranean basin and Transcaucasia differ significantly from the conditions of nearby, but more northern regions.

In Asia, cold air freely penetrates to the mountain ranges that border the territory of the Central Asian republics from the south and east, so winters in the Turan Lowland are quite cold. But such mountain ranges as the Pamirs, Tien Shan, Altai, Tibetan Plateau, not to mention
The Himalayas are obstacles to further penetration of cold air masses to the south. In rare cases, significant advective cooling is observed, however, in India: in Punjab on average by 8 - 9 ° C, and in March
In 1911, the temperature dropped by 20° C. At the same time, cold masses flow around the mountain ranges from the west. Cold air penetrates the southeast more easily and more often
Asia, without encountering significant obstacles along the way.

There are no latitudinal mountain ranges in North America. Therefore, cold masses of Arctic air can spread unimpeded to Florida and the Gulf of Mexico.

Over the oceans, intrusions of cold air masses can penetrate deep into the tropics. Of course, cold air gradually warms up over warm water, but it can still cause noticeable drops in temperature.

Intrusions of sea air from the mid-latitudes of the Atlantic Ocean into
Europe is created by warming in winter and cooling in summer. The further into the depths
Eurasia, the less frequent the Atlantic air masses become and the more their initial properties change over the continent. But still, the influence of invasions from the Atlantic on climate can be traced back to
Central Siberian Plateau and Central Asia.

Tropical air invades Europe both in winter and summer from the North
Africa and from the low latitudes of the Atlantic. In summer, air masses similar in temperature to air masses of the tropics and therefore also called tropical air form in the south of Europe or come to Europe from
Kazakhstan and Central Asia. In the Asian territory of Russia in the summer there are intrusions of tropical air from Mongolia, Northern China, from the southern regions of Kazakhstan and from the deserts of Central Asia.

In some cases, strong temperature increases (up to +30° C) during summer incursions of tropical air extend to the Far North
Russia.

Tropical air invades North America from both the Pacific and
Atlantic Ocean, especially from the Gulf of Mexico. On the continent itself, masses of tropical air form over Mexico and the southern United States.

Even in the region of the North Pole, air temperatures in winter sometimes rise to zero as a result of advection from temperate latitudes, and the warming can be traced throughout the troposphere.

Movements of air masses leading to advective temperature changes are associated with cyclonic activity.

On smaller spatial scales, sharp non-periodic temperature changes can be associated with hair dryers in mountainous areas, i.e. with adiabatic heating of air during its downward movement.

Since non-periodic temperature changes occur every year differently, then the average annual air temperature at each individual point in different years different. Thus, in Moscow in 1862 the average annual temperature was +1.2° C, in 1925 +6.1° C. average temperature of a particular month in some years varies within even wider limits, especially for the winter months. Thus, in Moscow for 170 years, the average temperature in January fluctuated within 19 ° C (from -21 to -2 ° C), and in July - within 7 ° C (from
+15 to +22° C). But these are the extreme limits of fluctuations. On average, the temperature of one or another month of a particular year deviates from the long-term average for this month in winter by about 3 ° C and in summer by 1.5 ° C in one direction or the other.

The deviation of the average monthly temperature from the climatic norm is called the anomaly of the average monthly temperature for a given month. The long-term average value of the absolute values of monthly temperature anomalies can be taken as a measure of variability, which is greater, the more intense the non-periodic temperature changes in a given area, giving the same month a different character in different years. Therefore, the variability of average monthly temperatures increases with latitude: in the tropics it is small, in temperate latitudes it is significant, in a maritime climate it is less than in a continental climate.
The variability is especially great in the transition areas between marine and continental climates, where marine air masses may predominate in some years and continental ones in others.

Continental climate. The climate over the sea, characterized by small annual temperature amplitudes, can naturally be called marine, in contrast to the continental climate over land with large annual temperature amplitudes. The maritime climate also extends to the continental areas adjacent to the sea, over which the frequency of marine air masses is high. We can say that sea air brings a maritime climate to land.
Regions of the oceans where air masses from the nearby continent predominate have a continental rather than maritime climate.

The maritime climate is well defined in Western Europe, where all year round air transport from the Atlantic Ocean dominates. In the far west
In Europe, annual air temperature ranges are only a few degrees. With distance from the Atlantic Ocean inland, annual temperature amplitudes increase. In other words, the continental climate is increasing. IN
In Eastern Siberia, annual amplitudes reach several tens of degrees.
Summers here are hotter than in Western Europe, winters are much more severe.
The proximity of Eastern Siberia to the Pacific Ocean is not significant, since due to the conditions of the general circulation of the atmosphere, air from this ocean does not penetrate far into Siberia, especially in winter. Only in the Far East does the influx of air masses from the ocean in summer lower the temperature and thereby slightly reduce the annual amplitude.

CONTINENTALITY OF CLIMATE

climate, a set of climate properties determined by the influence of large land areas on the atmosphere and climate-forming processes. The main differences in the climate of continents and oceans are due to the peculiarities of their accumulation of heat. The surfaces of the continents heat up quickly and strongly during the day and summer and cool down at night and in winter. Over the oceans, this process is slowed down, since water masses during warm times of the day and year accumulate a large amount of heat in deep layers, which is gradually returned to the atmosphere in cold times. Therefore, air temperature and other climate characteristics change (from day to night and from summer to winter) over the continents more than over the oceans (see Continental climate, Marine climate). The movement of air masses leads to the spread of the influence of the oceans on the climate of adjacent parts of the continents and to the reverse influence of the continents on the climate of the oceans. Thus, the climate may be more or less continental (or oceanic), which can be expressed quantitatively; Most often, air temperature is considered as a function of the annual amplitude of air temperature.

Lit.: Khromov S. G., On the issue of continental climate, "Proceedings of the All-Russian Geographical Society", 1957, vol. 89, century. 3; Rubinshtein E. S., On the influence of the distribution of oceans and land on the globe, ibid., 1953, v. 85, century. 4 .

S. P. Khromov.

Great Soviet Encyclopedia, TSB. 2012

Key Features

Temperate continental climates are found only in the Northern Hemisphere. It is characteristic of both the Cordillera region and Central Europe. The temperate continental climate of Russia is manifested in Yakutia, Magadan region, in Siberia and Transbaikalia. Moving inland, the air loses moisture, making the climate more severe. Therefore, the more distant an area is from the sea or ocean, the more continental the climate will be.

Winter months

The temperate continental climate has a pronounced seasonality. The main seasons of the year - summer and winter - are worth considering separately. During the cold season, the earth's surface and atmosphere cool, leading to the formation of the Asian Anticyclone. It spreads to Siberia, Kazakhstan and Mongolia, and sometimes reaches the south- of Eastern Europe. The result is a harsh winter with strong air fluctuations within just a few days, when the thaw suddenly turns into frost down to minus thirty. the form of snow, which persists in areas east of Warsaw. The maximum height of the cover can reach ninety centimeters - such snowdrifts occur in Western Siberia. A large amount of snow protects the soil from freezing and provides it with moisture when spring comes.

Summer months

The temperate continental climate of Russia and Eastern Europe is characterized by a fairly rapid onset of summer. The increasing amount of solar heat warms the heat coming to the mainland from the ocean. Average monthly temperatures in July are just under twenty degrees. The annual amount of precipitation, most of which occurs in the summer, ranges from three hundred to eight hundred millimeters in these regions. The amount varies only on the slopes of the Alps. There can be more than two thousand millimeters of precipitation there. It is worth noting a decrease in their number in the direction from west to east. In North America the situation is inversely proportional. In Asian areas, evaporation exceeds natural precipitation and droughts may occur.

Features of vegetation

The temperate continental climate is characterized by deciduous forests. They consist of two tiers - trees and shrubs. The herbaceous cover has a greater number of species than other flora options. In addition, it is also divided into several tiers. The forests are characterized by branching with a dense crown. The seasons are not conducive to year-round vegetation. they shed leaves - simple, jagged or lobed, thin and unable to tolerate either drought or frost. The moderate continental climate of the temperate zone can be distinguished by both broad- and small-leaved species. The first include ash trees, maples, oaks, lindens, and elms. The second ones are aspen, alder and birch.

In addition, the forest can be divided into types such as monodominant and polydominant. The first are characteristic of Europe - a specific species predominates there. The latter are found in Asia, North America and Chile: the forest consists of many different species. In warm areas, evergreen species are found among deciduous trees, as well as vines - grape, legume, honeysuckle or euonymus. Despite the annual fall of leaves, the forests of these zones are characterized by poorly developed litter: the temperate continental climate contributes to its rapid decomposition. This creates excellent conditions for bacteria and earthworms. At the same time, the layer of foliage becomes an obstacle to moss, which grows in such a forest only at the roots of trees and in places protruding from the soil. The soil in this climate is podzolic, brown, carbonate or gley.

Characteristic animals

The fauna of a continental climate is located in forests very homogeneously. This is a combination of arboreal, terrestrial, herbivorous, and predatory animals. In the zones of deciduous forests there are a lot of amphibians and reptiles - there are twice as many of them here as in the tundra. The abundance of light, dense undergrowth, and lush grass provide excellent conditions for various animals. Here you can find animals that feed on seeds and nuts - rodents, squirrels, and numerous birds, such as blackbirds, western nightingales, little robins, great tits, and blue tits. In almost every forest you can find chaffinches and greenfinches, orioles, and in remote corners - wood pigeons. Larger animals are represented by stoats, badgers, wolves, foxes, lynxes and bears. They live throughout Europe and large parts of Asia. Unique species are found in uninhabited corners - wild cats, pine martens, and ferrets. The presence of herbivores is high - wapiti, bison and chamois are also found.

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

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

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

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

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

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

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

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

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

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

Climate zones

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

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

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

The main climatic zones are:

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

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

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

Diversity of Earth's climates

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

Arctic and Antarctic climate zones

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

Table 1. Climates of the Earth

Climate type	Climate zone	Average temperature, °C	Mode and amount of atmospheric precipitation, mm	Atmospheric circulation	Territory
Climate type	Climate zone		Mode and amount of atmospheric precipitation, mm	Atmospheric circulation	Territory
Equatorial	Equatorial		During a year. 2000	In areas of low atmospheric pressure, warm and humid equatorial air masses form	Equatorial regions of Africa, South America and Oceania
Tropical monsoon	Subequatorial		Mainly during the summer monsoon, 2000		South and Southeast Asia, Western and Central Africa, Northern Australia
tropical dry	Tropical		During the year, 200		North Africa, Central Australia
Mediterranean	Subtropical		Mainly in winter, 500	In summer there are anticyclones at high atmospheric pressure; in winter - cyclonic activity	Mediterranean, Southern coast of Crimea, South Africa, Southwestern Australia, Western California
Subtropical dry	Subtropical		During a year. 120	Dry continental air masses	Interiors of continents
Temperate marine	Moderate		During a year. 1000	Western winds	Western parts of Eurasia and North America
Temperate continental	Moderate		During a year. 400	Western winds	Interiors of continents
Moderate monsoon	Moderate		Mainly during the summer monsoon, 560		Eastern edge of Eurasia
Subarctic	Subarctic		During the year, 200	Cyclones predominate	Northern edges of Eurasia and North America
Arctic (Antarctic)	Arctic (Antarctic)		During the year, 100	Anticyclones predominate	The Arctic Ocean and mainland Australia

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

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

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

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

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

Temperate climate zone

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

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

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

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

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

In conditions of sufficient moisture, broad-leaved forests develop on the coasts, and in conditions of excess moisture, coniferous forests develop. The lack of summer heat reduces the upper limit of the forest in the mountains to 500-700 m above sea level.

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

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

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

Unlike Eurasia, the eastern coast of North America is characterized by maritime climate, which is expressed in the predominance of winter precipitation and the maritime type of annual variation in air temperature: the minimum occurs in February and the maximum in August, when the ocean is warmest.

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

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

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

In midwinter, the continental air in the lower layers becomes even colder than the Arctic air. This very cold air of the Asian anticyclone extends to Western Siberia, Kazakhstan, and the southeastern regions of Europe.

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

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

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

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

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

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

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

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

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

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

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

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

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

Subtropical climate zone

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

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

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

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

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

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

Equatorial climate zone

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

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