Climate general information. Earth's climate

The concept of "climate"

Unlike the concept of “weather,” climate is more general concept. IN scientific literature the term was introduced back in the $II$ century. BC. ancient Greek astronomer Hipparchus. Literally translated, the term means “slope.” It is surprising that ancient scientists were well aware of the dependence of the physical and geographical conditions of the surface on the slope sun rays. They compared the climate of the planet with the position of Greece and believed that to the north of it lies a temperate climate zone, and even further north they are already moving icy deserts. To the south of Greece there are hot deserts, and in the Southern Hemisphere the climatic zonation will be repeated.
The ideas of ancient scientists about climate prevailed until the beginning of the 19th century. Over the course of many decades, the concept of “climate” has been transformed, and each time a new meaning has been invested in it.

Definition 1

Climate- This is a long-term weather pattern.

This short definition of climate does not mean that it is definitive. Today there is no single, generally accepted definition and different authors interpret it differently.

Climate depends on large processes on a planetary scale - on solar irradiation of the Earth's surface, on heat and moisture exchange between the atmosphere and the surface of the planet, atmospheric circulation, the action of the biosphere, on the characteristics of perennial snow cover and glaciers. Uneven distribution solar heat on the surface of the Earth, its spherical shape and rotation around its axis have led to a huge variety of climatic conditions. Scientists combined all these conditions in a certain way and identified $13$ latitudinal climatic zones, which are located more or less symmetrically relative to each other. The heterogeneity of climatic zones depends on their geographical location– they are located near the ocean or in the depths of the continent.

Climate is a complex system, all its components, which in one way or another exert their influence and cause changes over vast areas.

These components are:

• Atmosphere;
• Hydrosphere;
• Biosphere;
• Underlying surface.

Atmosphere- a central component of the climate system. The processes that arise in it greatly influence the weather and climate.

The World Ocean is very closely connected with the atmosphere, i.e. hydrosphere, which is second important component climate system. By mutually transferring heat, they influence weather and climate conditions. Weather that originates in the central parts of the ocean spreads to the continents, and the ocean itself has enormous heat capacity. Slowly heating up, it gradually gives up its heat, serving as a heat accumulator for the planet.

Depending on what surface the sun's rays fall on, they will heat it or be reflected back into the atmosphere. Snow and ice are the most reflective.

Continuous interaction of living and nonliving matter occurs in one of the largest shells of the Earth - biosphere. It is the environment for everything organic world. The processes operating in the biosphere contribute to the formation of oxygen, nitrogen, carbon dioxide and ultimately enter the atmosphere, influencing the climate.

Climate-forming factors

The diversity of climate and its features are determined by different geographical conditions and a number of factors called climate-forming.

These main factors include:

• Solar radiation;
• Atmospheric circulation;
• The nature of the earth's surface, i.e. terrain.

Note 1

These factors determine the climate anywhere on Earth. The most important thing is solar radiation. Only $45$% of radiation reaches the Earth's surface. All life processes and such climate indicators as pressure, cloudiness, precipitation, atmospheric circulation, etc. depend on the heat entering the surface of the planet.

Through atmospheric circulation, not only inter-latitudinal exchange of air occurs, but also its redistribution from the surface to the upper layers of the atmosphere and back. Thanks to air masses, clouds are transported, wind and precipitation form. Air masses redistribute pressure, temperature, and humidity.

Influence solar radiation and atmospheric circulation is qualitatively changed by such a climate-forming factor as terrain. High relief forms - ridges, mountain rises - are characterized by their specific features: mine temperature regime and its own precipitation regime, which depends on the exposure, orientation of the slopes and the height of the ridges. Mountainous terrain acts as a mechanical barrier to the path of air masses and fronts. Sometimes mountains act as boundaries of climatic regions; they can change the nature of the atmosphere or exclude the possibility of air exchange. Thanks to high landforms, there are many places on Earth where precipitation is very high or low. For example, the outskirts of Central Asia are protected by powerful mountain systems, which explains the dryness of its climate.

In mountainous areas, climate change occurs with altitude - the temperature becomes lower, atmospheric pressure drops, air humidity decreases, up to a certain altitude the amount of precipitation increases and then decreases. As a result of these features, mountain regions are distinguished altitude climate zones. Lowland areas practically do not distort the direct influence of climate-forming factors - they receive the amount of heat corresponding to the latitude and do not distort the direction of movement of air masses. In addition to the main climate-forming factors, a number of other factors will influence the climate.

Among them are:

• Distribution of land and sea;
• Remoteness of the territory from seas and oceans;
• Sea and continental air;
• Sea currents.

Changing of the climate

Currently, the world community is expressing great concern about climate change on the planet in the 21st century. An increase in the average temperature in the atmosphere and in the surface layer is the main change that can affect negative impact on natural ecosystems and on humans. Global warming becomes an important problem for the survival of humanity.

This problem is being studied by specialized international organizations, is widely discussed in international forums. Since $1988 under the auspices UNEP And WHO The International Commission on Climate Change (ICCC) is functioning. The commission evaluates all data on this problem, determines possible consequences climate change and outlines a response strategy. In 1992, a conference was held in Rio de Janeiro at which a special Convention on Climate Change was adopted.

As evidence of climate change, a number of scientists cite examples of an increase in average global temperature - hot and dry summers, mild winters, melting glaciers and rising sea levels, frequent and destructive typhoons and hurricanes. Studies have shown that in the $20s and $30s of the $20th century, warming affected the Arctic and adjacent areas of Europe, Asia, and North America.

Note 2

Brooks' research suggests that the climate has become wetter since the mid-17th century, with mild winters and cool summers. The increase in winter temperatures in the Arctic and mid-latitudes began in $1850. Winter temperatures in Northern Europe increased by $2.8 degrees over three months in the first $30 years of the 20th century, and southwesterly winds were predominant. average temperature in the western part of the Arctic for $1931-1935$. increased by $9$ degrees compared to the second half of the 19th century. As a result, the ice boundary retreated to the north. No one can say how long these climatic conditions will continue, just as no one can name the exact reasons for these climate change. But, nevertheless, there are attempts to explain climate fluctuations. The sun is the main driving force of climate. As a result of the fact that earth's surface heats up unevenly, causing winds and currents to form in the ocean. Solar activity is accompanied magnetic storms and warming.

Change in Earth's orbit, change magnetic field, changes in the size of oceans and continents, and volcanic eruptions have big influence on the planet's climate. These reasons are natural. It was they who changed the climate in geological epochs and until recently. They determined the beginning and end of long-term climate cycles such as ice ages. Solar and volcanic activity explains half temperature changes up to $1950$ - an increase in temperature is associated with solar activity, and a decrease in temperature is associated with volcanic activity. In the second half of the $XX$ century. scientists added one more factor - anthropogenic associated with human activity. The result of this factor was an increase in greenhouse effect, which had an impact on climate change $8$ times greater than the impact of changes in solar activity over the past two centuries. The problem exists, and scientists are working to solve it different countries, including Russia.

Features of the climate of North America The climate of North America is influenced by climate-forming factors: the geographical location of the continent, its size and configuration, relief, sea currents. Due to its geographical location, size and significant extent from north to south, the territory of the continent is part of all climatic zones except the equatorial one. The most wide part The mainland falls on moderate latitudes. Therefore, the climate in temperate zone […]

The main features of Africa's climate are determined by the location of most of it in equatorial and tropical latitudes. At high air temperatures, the main differences in the climate of individual regions are determined by the amount of precipitation and the duration of the rainy season. Vast areas lack moisture. Africa is characterized by the transport of tropical air by trade winds. High banks make it difficult for wet winds to enter. The western shores in tropical latitudes are washed by cold […]

Climate zones The cycle of heat, moisture and the general circulation of the atmosphere form the weather and climate in the geographic envelope. The types of air masses and the characteristics of their circulation at different latitudes create the conditions for the formation of the Earth's climate. The dominance of one air mass throughout the year determines the boundaries of climate zones. Climatic zones are territories that encircle the Earth in a continuous or intermittent strip; Friend […]

The territory of this practically steppe country, which does not have access to the seas, has the most continental climate: dry, cold winters with severe frosts and strong winds, and hot, dusty summers. Even in ancient times, horse tribes roamed the high plains and low mountains. That is why one of the symbols of Mongolia still remains the yurt - a portable dwelling made of felt. […]

In the past, the Earth's climate has changed repeatedly: warming eras have followed. ice ages. The main reasons for such changes were the movement of continents, changes in the tilt of the earth's axis and the speed of rotation of our planet. Climates of the Earth Climate is a long-term weather regime characteristic of a given territory. Climate is more constant than weather; it remains the same over time. The idea of ​​climate is formed from many years of weather observations. Different regions of the Earth have different average temperatures [...]

We feel the weather every day when we go outside. From the weather forecast we learn about its changes, about impending thunderstorms and hurricanes, severe frosts and snowfalls, rain and fog. Weather Weather is the state of the troposphere at a given place in given time. Weather is characterized by a number of indicators called meteorological elements. These include air temperature and humidity, atmospheric pressure, cloudiness, […]

The process of formation of relief and climate The relief of Eastern Europe, modern plains, lowlands and mountains were formed as a result of complex and long-term geological development. The most ancient structure of crystalline rocks, representing the geological basis of Eastern Europe, is the Russian platform, in the rigid foundation of which mining processes stopped relatively early. This, as well as the activity of glaciers, explains the predominance of the flat landscape. In the same place where the platform came into contact with [...]

An idea of ​​the climate of any area can be obtained over a period of 30-40 years, since during this time all possible combinations of weather conditions occur here: very cold or warm winters, hot or cool summers, rainy and dry seasons, droughts and years when atmospheric precipitation falls one and a half to two times more than normal. Many factors influence climate formation. The primary factor is solar energy. It is known that the Sun sends […]

Jan Feb March Apr May June July Aug Sep Oct Nov Dec Daytime temperature in degrees Celsius 13 13 15 18 23 27 30 30 27 23 18 15 Night temperature in degrees Celsius 5 6 7 9 13 16 18 18 16 13 10 6 Water temperature in degrees mustache Celsius 15 14 15 16 […]

The weather on the island of Crete is moderate, which characterizes its winters as rainy, and its summers as hot and dry. The climate of the island of Crete is Mediterranean, temperate. There are special weather differences in Crete between the mountainous and coastal areas, as well as its eastern and western parts. In particular, the coastal zone is characterized by moderate winters and dry, hot summers. The rainy season continues from […]

Climatic conditions in different parts of Crimea are not the same. This is explained by the influence of two main factors: the mountains and the seas washing the peninsula. The mountains serve as a barrier, trapping the cold continental and arctic air flowing here, and the sea, being a powerful heat regulator, softens the climate of the coastal strip. The South Coast has a Mediterranean climate. Winter in its western part is warm, humid, […]

The weather in Germany is characterized by a moderate climate. As for the climate in Germany, it really “turned its face” to the German residents. Its moderation allows you not only to enjoy the warm German weather, but also to run a household. Winters in Germany are devoid of severe frosts. Although, the further a German city is located from the sea line, the harsher it is in Germany weather in winter […]

Arctic belt B Arctic belt Arctic air masses dominate throughout the year. In winter, there is no solar radiation (polar night) or its influx is very small due to the low position of the Sun. The air temperature is very low and there is little precipitation. The ocean is covered with drifting ice of high concentration. Repeated meteorological conditions are typical. In summer, the influx of solar energy is significant and continuous (polar day), but the height of the Sun […]

The weather elements include temperature, pressure, wind, air humidity, visibility range, precipitation, cloudiness, which are zonal in their manifestations and interrelated. Air temperature directly depends on the amount of solar heat entering the Earth, which is determined primarily by the geographic latitude of the area: the closer to the equator, the higher the air temperature. Wind is the horizontal movement of air [...]

Weather is the state of the troposphere in a given place at a given time. Weather is characterized by the totality of the values ​​of all meteorological elements considered and is rarely stable, changing throughout the day and throughout the year. Climate (from the Greek Mima - slope) is a long-term weather pattern characteristic of a given area. Climate, unlike weather, is characterized by stability. He is characterized not only [...]

In the direction from north to south, our country is located in the arctic, subarctic and temperate climatic zones. But significant climate changes are also observed within each zone: both when moving from west to east (climatic regions), and when moving from north to south (zonal climate types). For example, there are five subtypes of the temperate climate zone: temperate continental, […]

The distribution of temperatures over the Earth's surface depends on two factors: on the radiation balance and on the circulation of air masses, which means that the air temperature in Russia varies greatly according to the seasons of the year. Due to the negative radiation balance in winter, significant cooling of the surface occurs. The location of January isotherms on climate maps clearly shows that their position has little connection […]

The formation of the country's climate is influenced by the following factors: Geographical location of the territory. It is they who determine the main features of the climate. There is a clear change associated with geographic location temperature conditions according to the seasons of the year, varying degrees of humidity, a wide variety of climates. The distribution of solar radiation and the circulation of air masses depend on the geographical location. The geographical position of Russia is characterized, first of all, by its large extent […]

Arctic climate zone. Arctic climate. The Arctic type of climate is represented on the islands of the Arctic Ocean and in the far north of Siberia. This is the Arctic climate zone and all year round Arctic air masses dominate here. Due to its geographical location, the area has very little solar radiation. In winter, under polar night conditions, the surface receives virtually no solar heat and average air temperatures […]

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 marine 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 cloudiness, uniform and fairly a large number of atmospheric 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 of the warm current, is available all year round covered with a thick layer of ice.

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- 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 Atlantic Ocean Therefore, winters in this area are relatively mild.

Regions of the 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 soil 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, blizzards, etc.). In the 20th century in number climate indicators included the characteristics of the elements of the heat balance of the earth's surface, such as total solar radiation, radiation balance, the amount of heat exchange between the earth's surface and the atmosphere, and heat consumption for evaporation. Complex indicators are also used, i.e. functions of several elements: various coefficients, factors, indices (for example, continentality, aridity, moisture), etc.

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 zones, air masses change seasonally. They come here from neighboring zones, so the climate of the subequatorial zone in summer is similar to the climate of the equatorial zone, and in winter - to the tropical climate; The climate of the subtropical zones in summer is similar to the climate of the tropical 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. For example, in the tropical zone of Africa, 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 An altitudinal zone is formed 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 0 °C. Into the dark winter time During the year, these regions receive absolutely no solar radiation, although there are twilights and auroras. Even in summer, the sun's rays 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 climate Arctic, since the southern continent is different large sizes and altitudes, 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
Equatorial	Equatorial			During a year. 2000	Warm and humid equatorial air masses form in areas of low atmospheric pressure	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, South coast Crimea, South Africa, South Western 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 of the atlas). In winter, arctic air predominates here, which forms in areas of high pressure. Arctic air spreads to the eastern regions of Canada 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 sea ​​temperate 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 on the coasts, developed broadleaf forests, and in conditions of excess - conifers. 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 monsoonal features and is accompanied seasonal change winds: in winter, north-western currents predominate, in summer - south-eastern 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 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 east coast of North America is characterized by monkfish climate, which are expressed in the predominance of winter precipitation and marine type annual progress air temperatures: 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. IN winter months With a negative radiation balance, the earth's surface cools. The cooling effect of the land surface on the surface layers of air is especially great in Asia, where 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 one is very cold air The Asian anticyclone extends to Western Siberia, Kazakhstan, and 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 geographical features continental territories. 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 into the land of the Baltic and North Seas. 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, 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 V 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 winter, cool summers and little 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 of 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 are 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, foggy, and the most warm month- 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. Average annual precipitation under conditions 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 basins South America and Congo in Africa, on the Malacca Peninsula and on the islands of Southeast Asia. Usually average annual temperature 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. Humid air, cloudiness and dense vegetation cover prevent night cooling and maintain maximum temperatures. daytime temperatures below +37 °C, lower than in higher 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.

On Earth, it determines the nature of many features of nature. Climatic conditions also greatly influence the lives, economic activities of people, their health and even biological features. At the same time, the climates of individual territories do not exist in isolation. They are parts of a single atmospheric process for the entire planet.

Climate classification

Earth's climates, which have similar features, are combined into certain types, which replace each other in the direction from the equator to the poles. In each hemisphere there are 7 climatic zones, of which 4 are main and 3 are transitional. This division is based on placement according to to the globe air masses with different properties and characteristics of air movement in them.

In the main belts, one air mass. In the equatorial zone - equatorial, in the tropical - tropical, in the temperate - air of temperate latitudes, in the Arctic (Antarctic) - arctic (Antarctic). IN transition belts, located between the main ones, alternately enter from the adjacent main belts in different seasons of the year. Here, conditions change seasonally: in summer they are the same as in the neighboring warmer zone, in winter they are the same as in the neighboring colder zone. Along with the change in air masses in the transition zones, the weather also changes. For example, in subequatorial belt Summer is hot and rainy, while winter is cooler and drier.

The climate within the belts is heterogeneous. Therefore, the belts are divided into climatic regions. Above the oceans, where sea air masses are formed, there are areas of oceanic climates, and above the continents - continental climates. In many climatic zones on the western and eastern coasts of the continents, special types of climate are formed, differing from both continental and oceanic. The reason for this is the interaction of marine and continental air masses, as well as the presence of ocean currents.

Hot ones include and. These areas constantly receive a significant amount of heat due to the high angle of incidence of the sun's rays.

In the equatorial belt, the equatorial air mass dominates throughout the year. The heated air constantly rises in conditions, which leads to the formation of rain clouds. There is heavy rainfall here every day, often with . The amount of precipitation is 1000-3000 mm per year. This is more than the amount of moisture that can evaporate. The equatorial zone has one season of the year: always hot and humid.

IN tropical zones A tropical air mass dominates throughout the year. In it, air descends from the upper layers of the troposphere to the earth's surface. As it descends, it heats up, and even over the oceans no clouds form. Clear weather prevails, in which the sun's rays strongly heat the surface. Therefore on land average in summer higher than in the equatorial zone (up to +35 ° WITH). Winter temperatures are lower than summer temperatures due to a decrease in the angle of incidence of sunlight. Due to the lack of clouds there is very little precipitation throughout the year, so on land it is common tropical desert. These are the hottest areas of the Earth, where temperature records are recorded. The exception is the eastern shores of the continents, which are washed by warm currents and are influenced by trade winds blowing from the oceans. Therefore, there is a lot of rainfall here.

The territory of subequatorial (transitional) belts is occupied by a humid equatorial air mass in summer, and dry tropical air in winter. Therefore, there are hot and rainy summers and dry and also hot - due to the high position of the Sun - winter.

Temperate climate zones

They occupy about 1/4 of the Earth's surface. They have sharper seasonal differences in temperature and precipitation than hot zones. This is due to a significant decrease in the angle of incidence of sunlight and increased complexity of circulation. They contain air of temperate latitudes all year round, but there are frequent intrusions of arctic and tropical air.

The Southern Hemisphere is dominated by an oceanic temperate climate with cool summers (from +12 to +14 °C), mild winters (from +4 to +6 °C) and heavy precipitation (about 1000 mm per year). In the Northern Hemisphere, large areas are occupied by continental temperate and. His main feature- pronounced changes in temperature across seasons.

The western shores of the continents receive moist air from the oceans all year round, brought from the western temperate latitudes; there is a lot of precipitation here (1000 mm per year). Summers are cool (up to + 16 °C) and humid, and winters are wet and warm (from 0 to +5 °C). Moving from west to east into the interior of the continents, the climate becomes more continental: the amount of precipitation decreases, summer temperatures increase, and winter temperatures decrease.

A monsoon climate is formed on the eastern shores of the continents: summer monsoons bring heavy precipitation from the oceans, and winter monsoons, blowing from the continents to the oceans, are associated with frosty and drier weather.

The subtropical transition zones receive air from temperate latitudes in winter, and tropical air in summer. The continental subtropical climate is characterized by hot (up to +30 °C) dry summers and cool (0 to +5 °C) and somewhat wetter winters. There is less precipitation per year than can evaporate, so deserts and deserts predominate. There is a lot of precipitation on the coasts of the continents, and on the western shores it is rainy in winter due to westerly winds from the oceans, and on the eastern shores it is rainy in summer due to the monsoons.

Cold climate zones

During the polar day, the earth's surface receives little solar heat, and during the polar night it does not heat up at all. Therefore, the Arctic and Antarctic air masses are very cold and contain little. The Antarctic continental climate is the most severe: exceptionally frosty winters and cold summers with sub-zero temperatures. Therefore, it is covered by a powerful glacier. In the Northern Hemisphere, the climate is similar, and above it is Arctic. It is warmer than Antarctic waters, since ocean waters, even covered with ice, provide additional heat.

In the subarctic and subantarctic zones, the Arctic (Antarctic) air mass dominates in winter, and air of temperate latitudes in summer. Summers are cool, short and humid, winters are long, harsh and with little snow.