What gas is in the earth's atmosphere. Atmosphere - the air envelope of the Earth

STRUCTURE OF THE ATMOSPHERE

Atmosphere(from ancient Greek ἀτμός - steam and σφαῖρα - ball) - the gas shell (geosphere) surrounding planet Earth. Its inner surface covers the hydrosphere and partly the earth's crust, while its outer surface borders the near-Earth part of outer space.

Physical properties

The thickness of the atmosphere is approximately 120 km from the Earth's surface. The total mass of air in the atmosphere is (5.1-5.3) 10 18 kg. Of these, the mass of dry air is (5.1352 ± 0.0003) 10 18 kg, the total mass of water vapor is on average 1.27 10 16 kg.

The molar mass of clean dry air is 28.966 g/mol, and the density of air at the sea surface is approximately 1.2 kg/m3. The pressure at 0 °C at sea level is 101.325 kPa; critical temperature - −140.7 °C; critical pressure - 3.7 MPa; C p at 0 °C - 1.0048·10 3 J/(kg·K), C v - 0.7159·10 3 J/(kg·K) (at 0 °C). Solubility of air in water (by mass) at 0 °C - 0.0036%, at 25 °C - 0.0023%.

The following are accepted as “normal conditions” at the Earth’s surface: density 1.2 kg/m3, barometric pressure 101.35 kPa, temperature plus 20 °C and relative humidity 50%. These conditional indicators have purely engineering significance.

The structure of the atmosphere

The atmosphere has a layered structure. The layers of the atmosphere differ from each other in air temperature, its density, the amount of water vapor in the air and other properties.

Troposphere(Ancient Greek τρόπος - “turn”, “change” and σφαῖρα - “ball”) - the lower, most studied layer of the atmosphere, 8-10 km high in the polar regions, up to 10-12 km in temperate latitudes, at the equator - 16-18 km.

When rising in the troposphere, the temperature decreases by an average of 0.65 K every 100 m and reaches 180-220 K in the upper part. This upper layer of the troposphere, in which the decrease in temperature with height stops, is called the tropopause. The next layer of the atmosphere, located above the troposphere, is called the stratosphere.

More than 80% of the total mass of atmospheric air is concentrated in the troposphere, turbulence and convection are highly developed, the predominant part of water vapor is concentrated, clouds arise, atmospheric fronts form, cyclones and anticyclones develop, as well as other processes that determine weather and climate. The processes occurring in the troposphere are caused primarily by convection.

The part of the troposphere within which the formation of glaciers on the earth's surface is possible is called chionosphere.

Tropopause(from the Greek τροπος - turn, change and παῦσις - stop, termination) - a layer of the atmosphere in which the decrease in temperature with height stops; transition layer from the troposphere to the stratosphere. In the earth's atmosphere, the tropopause is located at altitudes from 8-12 km (above sea level) in the polar regions and up to 16-18 km above the equator. The height of the tropopause also depends on the time of year (in summer the tropopause is located higher than in winter) and cyclonic activity (in cyclones it is lower, and in anticyclones it is higher)

The thickness of the tropopause ranges from several hundred meters to 2-3 kilometers. In the subtropics, tropopause breaks are observed due to powerful jet currents. The tropopause over certain areas is often destroyed and re-formed.

Stratosphere(from Latin stratum - flooring, layer) - a layer of the atmosphere located at an altitude of 11 to 50 km. Characterized by a slight change in temperature in the 11-25 km layer (lower layer of the stratosphere) and an increase in temperature in the 25-40 km layer from −56.5 to 0.8 ° C (upper layer of the stratosphere or inversion region). Having reached a value of about 273 K (almost 0 °C) at an altitude of about 40 km, the temperature remains constant up to an altitude of about 55 km. This region of constant temperature is called the stratopause and is the boundary between the stratosphere and mesosphere. The air density in the stratosphere is tens and hundreds of times less than at sea level.

It is in the stratosphere that the ozone layer (“ozone layer”) is located (at an altitude of 15-20 to 55-60 km), which determines the upper limit of life in the biosphere. Ozone (O 3) is formed as a result of photochemical reactions most intensively at an altitude of ~30 km. The total mass of O 3 would amount to a layer 1.7-4.0 mm thick at normal pressure, but this is enough to absorb life-destructive ultraviolet radiation from the Sun. The destruction of O 3 occurs when it interacts with free radicals, NO, and halogen-containing compounds (including “freons”).

In the stratosphere, most of the short-wave part of ultraviolet radiation (180-200 nm) is retained and the energy of short waves is transformed. Under the influence of these rays, magnetic fields change, molecules disintegrate, ionization occurs, and new formation of gases and other chemical compounds occurs. These processes can be observed in the form of northern lights, lightning and other glows.

In the stratosphere and higher layers, under the influence of solar radiation, gas molecules dissociate into atoms (above 80 km CO 2 and H 2 dissociate, above 150 km - O 2, above 300 km - N 2). At an altitude of 200-500 km, ionization of gases also occurs in the ionosphere; at an altitude of 320 km, the concentration of charged particles (O + 2, O − 2, N + 2) is ~ 1/300 of the concentration of neutral particles. In the upper layers of the atmosphere there are free radicals - OH, HO 2, etc.

There is almost no water vapor in the stratosphere.

Flights into the stratosphere began in the 1930s. The flight on the first stratospheric balloon (FNRS-1), which was made by Auguste Picard and Paul Kipfer on May 27, 1931 to an altitude of 16.2 km, is widely known. Modern combat and supersonic commercial aircraft fly in the stratosphere at altitudes generally up to 20 km (although the dynamic ceiling can be much higher). High-altitude weather balloons rise up to 40 km; the record for an unmanned balloon is 51.8 km.

Recently, in US military circles, much attention has been paid to the development of layers of the stratosphere above 20 km, often called “pre-space”. « near space» ). It is assumed that unmanned airships and solar-powered aircraft (like NASA Pathfinder) will be able to remain at an altitude of about 30 km for a long time and provide surveillance and communications to very large areas, while remaining low-vulnerable to air defense systems; Such devices will be many times cheaper than satellites.

Stratopause- a layer of the atmosphere that is the boundary between two layers, the stratosphere and the mesosphere. In the stratosphere, temperature increases with increasing altitude, and the stratopause is the layer where the temperature reaches its maximum. The temperature of the stratopause is about 0 °C.

This phenomenon is observed not only on Earth, but also on other planets that have an atmosphere.

On Earth, the stratopause is located at an altitude of 50 - 55 km above sea level. Atmospheric pressure is about 1/1000 that of sea level.

Mesosphere(from the Greek μεσο- - “middle” and σφαῖρα - “ball”, “sphere”) - a layer of the atmosphere at altitudes from 40-50 to 80-90 km. Characterized by an increase in temperature with altitude; the maximum (about +50°C) temperature is located at an altitude of about 60 km, after which the temperature begins to decrease to −70° or −80°C. This decrease in temperature is associated with the vigorous absorption of solar radiation (radiation) by ozone. The term was adopted by the Geographical and Geophysical Union in 1951.

The gas composition of the mesosphere, like that of the underlying atmospheric layers, is constant and contains about 80% nitrogen and 20% oxygen.

The mesosphere is separated from the underlying stratosphere by the stratopause, and from the overlying thermosphere by the mesopause. Mesopause basically coincides with turbopause.

Meteors begin to glow and, as a rule, completely burn up in the mesosphere.

Noctilucent clouds may appear in the mesosphere.

For flights, the mesosphere is a kind of “dead zone” - the air here is too rarefied to support airplanes or balloons (at an altitude of 50 km the air density is 1000 times less than at sea level), and at the same time too dense for artificial flights satellites in such low orbit. Direct studies of the mesosphere are carried out mainly using suborbital weather rockets; In general, the mesosphere has been studied less well than other layers of the atmosphere, which is why scientists have nicknamed it the “ignorosphere.”

Mesopause

Mesopause- a layer of the atmosphere that separates the mesosphere and thermosphere. On Earth it is located at an altitude of 80-90 km above sea level. At the mesopause there is a temperature minimum, which is about −100 °C. Below (starting from an altitude of about 50 km) the temperature drops with height, higher (up to an altitude of about 400 km) it rises again. The mesopause coincides with the lower boundary of the region of active absorption of X-ray and short-wave ultraviolet radiation from the Sun. At this altitude noctilucent clouds are observed.

Mesopause occurs not only on Earth, but also on other planets that have an atmosphere.

Karman Line- altitude above sea level, which is conventionally accepted as the boundary between the Earth’s atmosphere and space.

According to the Fédération Aéronautique Internationale (FAI) definition, the Karman line is located at an altitude of 100 km above sea level.

The height was named after Theodore von Karman, an American scientist of Hungarian origin. He was the first to determine that at approximately this altitude the atmosphere becomes so rarefied that aeronautics becomes impossible, since the speed of the aircraft required to create sufficient lift becomes greater than the first cosmic speed, and therefore, to achieve greater altitudes it is necessary to use astronautics.

The Earth's atmosphere continues beyond the Karman line. The outer part of the earth's atmosphere, the exosphere, extends to an altitude of 10 thousand km or more; at this altitude, the atmosphere consists mainly of hydrogen atoms that are capable of leaving the atmosphere.

Achieving the Karman Line was the first condition for receiving the Ansari X Prize, as this is the basis for recognizing the flight as a space flight.

Earth's atmosphere

Atmosphere(from. Old Greekἀτμός - steam and σφαῖρα - ball) - gas shell ( geosphere), surrounding the planet Earth. Its inner surface covers hydrosphere and partially bark, the outer one borders on the near-Earth part of outer space.

The set of branches of physics and chemistry that study the atmosphere is usually called atmospheric physics. The atmosphere determines weather on the surface of the Earth, studying weather meteorology, and long-term variations climate - climatology.

The structure of the atmosphere

The structure of the atmosphere

Troposphere

Its upper limit is at an altitude of 8-10 km in polar, 10-12 km in temperate and 16-18 km in tropical latitudes; lower in winter than in summer. The lower, main layer of the atmosphere. Contains more than 80% of the total mass of atmospheric air and about 90% of all water vapor present in the atmosphere. In the troposphere are highly developed turbulence And convection, arise clouds, are developing cyclones And anticyclones. Temperature decreases with increasing altitude with average vertical gradient 0.65°/100 m

Stratosphere

A layer of the atmosphere located at an altitude of 11 to 50 km. Characterized by a slight change in temperature in the 11-25 km layer (lower layer of the stratosphere) and an increase in the 25-40 km layer from −56.5 to 0.8 ° WITH(upper layer of the stratosphere or region inversions). Having reached a value of about 273 K (almost 0 ° C) at an altitude of about 40 km, the temperature remains constant up to an altitude of about 55 km. This region of constant temperature is called stratopause and is the boundary between the stratosphere and mesosphere.

Stratopause

The boundary layer of the atmosphere between the stratosphere and mesosphere. In the vertical temperature distribution there is a maximum (about 0 °C).

Mesosphere

Earth's atmosphere

Mesosphere begins at an altitude of 50 km and extends to 80-90 km. Temperature decreases with height with an average vertical gradient of (0.25-0.3)°/100 m. The main energy process is radiant heat transfer. Complex photochemical processes involving free radicals, vibrationally excited molecules, etc., cause the glow of the atmosphere.

Mesopause

Transitional layer between the mesosphere and thermosphere. There is a minimum in the vertical temperature distribution (about -90 °C).

Karman Line

The height above sea level, which is conventionally accepted as the boundary between the Earth's atmosphere and space.

Thermosphere

Main article: Thermosphere

The upper limit is about 800 km. The temperature rises to altitudes of 200-300 km, where it reaches values of the order of 1500 K, after which it remains almost constant to high altitudes. Under the influence of ultraviolet and x-ray solar radiation and cosmic radiation, air ionization occurs (“ auroras") - main areas ionosphere lie inside the thermosphere. At altitudes above 300 km, atomic oxygen predominates.

Atmospheric layers up to an altitude of 120 km

Exosphere (scattering sphere)

Exosphere- dispersion zone, the outer part of the thermosphere, located above 700 km. The gas in the exosphere is very rarefied, and from here its particles leak into interplanetary space ( dissipation).

Up to an altitude of 100 km, the atmosphere is a homogeneous, well-mixed mixture of gases. In higher layers, the distribution of gases by height depends on their molecular weights; the concentration of heavier gases decreases faster with distance from the Earth's surface. Due to the decrease in gas density, the temperature drops from 0 °C in the stratosphere to −110 °C in the mesosphere. However, the kinetic energy of individual particles at altitudes of 200-250 km corresponds to a temperature of ~1500 °C. Above 200 km, significant fluctuations in temperature and gas density in time and space are observed.

At an altitude of about 2000-3000 km, the exosphere gradually turns into the so-called near space vacuum, which is filled with highly rarefied particles of interplanetary gas, mainly hydrogen atoms. But this gas represents only part of the interplanetary matter. The other part consists of dust particles of cometary and meteoric origin. In addition to extremely rarefied dust particles, electromagnetic and corpuscular radiation of solar and galactic origin penetrates into this space.

The troposphere accounts for about 80% of the mass of the atmosphere, the stratosphere - about 20%; the mass of the mesosphere is no more than 0.3%, the thermosphere is less than 0.05% of the total mass of the atmosphere. Based on the electrical properties in the atmosphere, the neutronosphere and ionosphere are distinguished. It is currently believed that the atmosphere extends to an altitude of 2000-3000 km.

Depending on the composition of the gas in the atmosphere, they emit homosphere And heterosphere. Heterosphere - This is the area where gravity affects the separation of gases, since their mixing at such an altitude is negligible. This implies a variable composition of the heterosphere. Below it lies a well-mixed, homogeneous part of the atmosphere, called homosphere. The boundary between these layers is called turbo pause, it lies at an altitude of about 120 km.

Physical properties

The thickness of the atmosphere is approximately 2000 - 3000 km from the Earth's surface. Total mass air- (5.1-5.3)×10 18 kg. Molar mass clean dry air is 28.966. Pressure at 0 °C at sea level 101.325 kPa; critical temperature?140.7 °C; critical pressure 3.7 MPa; C p 1.0048×10 3 J/(kg K) (at 0 °C), C v 0.7159×10 3 J/(kg K) (at 0 °C). The solubility of air in water at 0 °C is 0.036%, at 25 °C - 0.22%.

Physiological and other properties of the atmosphere

Already at an altitude of 5 km above sea level, an untrained person develops oxygen starvation and without adaptation, a person’s performance is significantly reduced. The physiological zone of the atmosphere ends here. Human breathing becomes impossible at an altitude of 15 km, although up to approximately 115 km the atmosphere contains oxygen.

The atmosphere supplies us with the oxygen necessary for breathing. However, due to the drop in the total pressure of the atmosphere, as you rise to altitude, the partial pressure of oxygen decreases accordingly.

The human lungs constantly contain about 3 liters of alveolar air. Partial pressure oxygen in alveolar air at normal atmospheric pressure is 110 mm Hg. Art., carbon dioxide pressure - 40 mm Hg. Art., and water vapor - 47 mm Hg. Art. With increasing altitude, oxygen pressure drops, and the total vapor pressure of water and carbon dioxide in the lungs remains almost constant - about 87 mm Hg. Art. The supply of oxygen to the lungs will completely stop when the ambient air pressure becomes equal to this value.

At an altitude of about 19-20 km, the atmospheric pressure drops to 47 mm Hg. Art. Therefore, at this altitude, water and interstitial fluid begin to boil in the human body. Outside the pressurized cabin at these altitudes, death occurs almost instantly. Thus, from the point of view of human physiology, “space” begins already at an altitude of 15-19 km.

Dense layers of air - the troposphere and stratosphere - protect us from the damaging effects of radiation. With sufficient rarefaction of air, at altitudes of more than 36 km, ionizing agents have an intense effect on the body. radiation- primary cosmic rays; At altitudes of more than 40 km, the ultraviolet part of the solar spectrum is dangerous for humans.

As we rise to an ever greater height above the Earth's surface, such familiar phenomena observed in the lower layers of the atmosphere as the propagation of sound, the emergence of aerodynamic lift and resistance, heat transfer convection and etc.

In rarefied layers of air, distribution sound turns out to be impossible. Up to altitudes of 60-90 km, it is still possible to use air resistance and lift for controlled aerodynamic flight. But starting from altitudes of 100-130 km, concepts familiar to every pilot numbers M And sound barrier lose their meaning, there is a conditional Karman Line beyond which begins the sphere of purely ballistic flight, which can only be controlled using reactive forces.

At altitudes above 100 km, the atmosphere is deprived of another remarkable property - the ability to absorb, conduct and transmit thermal energy by convection (i.e. by mixing air). This means that various elements of equipment on the orbital space station will not be able to be cooled from the outside in the same way as is usually done on an airplane - with the help of air jets and air radiators. At such a height, as in space generally, the only way to transfer heat is thermal radiation.

Atmospheric composition

Composition of dry air

The Earth's atmosphere consists mainly of gases and various impurities (dust, water droplets, ice crystals, sea salts, combustion products).

The concentration of gases that make up the atmosphere is almost constant, with the exception of water (H 2 O) and carbon dioxide (CO 2).

Composition of dry air

Nitrogen
Oxygen
Argon
Water
Carbon dioxide
Neon
Helium
Methane
Krypton
Hydrogen
Xenon
Nitrous oxide

In addition to the gases indicated in the table, the atmosphere contains SO 2, NH 3, CO, ozone, hydrocarbons, HCl, HF, couples Hg, I 2 , and also NO and many other gases in small quantities. The troposphere constantly contains a large number of suspended solid and liquid particles ( aerosol).

History of atmospheric formation

According to the most common theory, the Earth's atmosphere has had four different compositions over time. Initially it consisted of light gases ( hydrogen And helium), captured from interplanetary space. This is the so-called primary atmosphere(about four billion years ago). At the next stage, active volcanic activity led to the saturation of the atmosphere with gases other than hydrogen (carbon dioxide, ammonia, water vapor). This is how it was formed secondary atmosphere(about three billion years before the present day). This atmosphere was restorative. Further, the process of atmosphere formation was determined by the following factors:

leakage of light gases (hydrogen and helium) into interplanetary space;

chemical reactions occurring in the atmosphere under the influence of ultraviolet radiation, lightning discharges and some other factors.

Gradually these factors led to the formation tertiary atmosphere, characterized by a much lower content of hydrogen and a much higher content of nitrogen and carbon dioxide (formed as a result of chemical reactions from ammonia and hydrocarbons).

Nitrogen

The formation of a large amount of N 2 is due to the oxidation of the ammonia-hydrogen atmosphere by molecular O 2, which began to come from the surface of the planet as a result of photosynthesis, starting 3 billion years ago. N2 is also released into the atmosphere as a result of denitrification of nitrates and other nitrogen-containing compounds. Nitrogen is oxidized by ozone to NO in the upper atmosphere.

Nitrogen N 2 reacts only under specific conditions (for example, during a lightning discharge). The oxidation of molecular nitrogen by ozone during electrical discharges is used in the industrial production of nitrogen fertilizers. They can oxidize it with low energy consumption and convert it into a biologically active form. cyanobacteria (blue-green algae) and nodule bacteria that form rhizobial symbiosis With legumes plants, so-called green manure.

Oxygen

The composition of the atmosphere began to change radically with the appearance on Earth living organisms, as a result photosynthesis accompanied by the release of oxygen and absorption of carbon dioxide. Initially, oxygen was spent on the oxidation of reduced compounds - ammonia, hydrocarbons, nitrous form gland contained in the oceans, etc. At the end of this stage, the oxygen content in the atmosphere began to increase. Gradually, a modern atmosphere with oxidizing properties formed. Since this caused serious and abrupt changes in many processes occurring in atmosphere, lithosphere And biosphere, this event was called Oxygen disaster.

During Phanerozoic the composition of the atmosphere and oxygen content underwent changes. They correlated primarily with the rate of deposition of organic sediment. Thus, during periods of coal accumulation, the oxygen content in the atmosphere apparently significantly exceeded the modern level.

Carbon dioxide

The content of CO 2 in the atmosphere depends on volcanic activity and chemical processes in the earth's shells, but most of all - on the intensity of biosynthesis and decomposition of organic matter in biosphere Earth. Almost the entire current biomass of the planet (about 2.4 × 10 12 tons ) is formed due to carbon dioxide, nitrogen and water vapor contained in the atmospheric air. Buried in ocean, V swamps and in forests organic matter turns into coal, oil And natural gas. (cm. Geochemical carbon cycle)

Noble gases

Source of inert gases - argon, helium And krypton- volcanic eruptions and decay of radioactive elements. The Earth in general and the atmosphere in particular are depleted of inert gases compared to space. It is believed that the reason for this lies in the continuous leakage of gases into interplanetary space.

Air pollution

Recently, the evolution of the atmosphere has begun to be influenced by Human. The result of his activities was a constant significant increase in the content of carbon dioxide in the atmosphere due to the combustion of hydrocarbon fuels accumulated in previous geological eras. Huge amounts of CO 2 are consumed during photosynthesis and absorbed by the world's oceans. This gas enters the atmosphere due to the decomposition of carbonate rocks and organic substances of plant and animal origin, as well as due to volcanism and human industrial activity. Over the past 100 years, the content of CO 2 in the atmosphere has increased by 10%, with the bulk (360 billion tons) coming from fuel combustion. If the growth rate of fuel combustion continues, then in the next 50 - 60 years the amount of CO 2 in the atmosphere will double and could lead to global climate change.

Fuel combustion is the main source of polluting gases ( CO, NO, SO 2 ). Sulfur dioxide is oxidized by atmospheric oxygen to SO 3 in the upper layers of the atmosphere, which in turn interacts with water and ammonia vapor, and the resulting sulfuric acid (H 2 SO 4 ) And ammonium sulfate ((NH 4 ) 2 SO 4 ) return to the surface of the Earth in the form of the so-called. acid rain. Usage internal combustion engines leads to significant atmospheric pollution with nitrogen oxides, hydrocarbons and lead compounds ( tetraethyl lead Pb(CH 3 CH 2 ) 4 ) ).

Aerosol pollution of the atmosphere is caused by both natural causes (volcanic eruptions, dust storms, entrainment of drops of sea water and plant pollen, etc.) and human economic activities (mining ores and building materials, burning fuel, making cement, etc.). Intense large-scale release of particulate matter into the atmosphere is one of the possible causes of climate change on the planet.

Everyone who has flown on an airplane is accustomed to this kind of message: “our flight takes place at an altitude of 10,000 m, the temperature outside is 50 ° C.” It seems nothing special. The farther from the surface of the Earth heated by the Sun, the colder it is. Many people think that the temperature decreases continuously with altitude and that the temperature gradually drops, approaching the temperature of space. By the way, scientists thought so until the end of the 19th century.

Let's take a closer look at the distribution of air temperature over the Earth. The atmosphere is divided into several layers, which primarily reflect the nature of temperature changes.

The lower layer of the atmosphere is called troposphere, which means “sphere of rotation.” All changes in weather and climate are the result of physical processes occurring precisely in this layer. The upper boundary of this layer is located where the decrease in temperature with height is replaced by its increase - approximately at an altitude of 15-16 km above the equator and 7-8 km above the poles. Like the Earth itself, the atmosphere, under the influence of the rotation of our planet, is also somewhat flattened above the poles and swells above the equator. However, this effect is expressed in the atmosphere much more strongly than in the solid shell of the Earth. In the direction from the Earth's surface to At the upper boundary of the troposphere, the air temperature decreases. Above the equator, the minimum air temperature is about -62 ° C, and above the poles - about -45 ° C. At moderate latitudes, more than 75% of the mass of the atmosphere is in the troposphere. In the tropics, about 90% is within the troposphere mass of the atmosphere.

In 1899, a minimum was found in the vertical temperature profile at a certain altitude, and then the temperature increased slightly. The beginning of this increase means the transition to the next layer of the atmosphere - to stratosphere, which means “sphere of the layer.” The term stratosphere means and reflects the previous idea of the uniqueness of the layer lying above the troposphere. The stratosphere extends to an altitude of about 50 km above the earth’s surface. Its peculiarity is, in particular, a sharp increase in air temperature. This increase in temperature is explained the reaction of ozone formation is one of the main chemical reactions occurring in the atmosphere.

The bulk of ozone is concentrated at altitudes of approximately 25 km, but in general the ozone layer is a highly extended shell, covering almost the entire stratosphere. The interaction of oxygen with ultraviolet rays is one of the beneficial processes in the earth’s atmosphere that contributes to the maintenance of life on Earth. The absorption of this energy by ozone prevents its excessive flow to the earth's surface, where exactly the level of energy that is suitable for the existence of terrestrial life forms is created. The ozonosphere absorbs some of the radiant energy passing through the atmosphere. As a result, a vertical air temperature gradient of approximately 0.62°C per 100 m is established in the ozonosphere, i.e., the temperature increases with altitude up to the upper limit of the stratosphere - the stratopause (50 km), reaching, according to some data, 0°C.

At altitudes from 50 to 80 km there is a layer of the atmosphere called mesosphere. The word "mesosphere" means "intermediate sphere", where the air temperature continues to decrease with height. Above the mesosphere, in a layer called thermosphere, the temperature rises again with altitude up to about 1000°C, and then drops very quickly to -96°C. However, it does not drop indefinitely, then the temperature increases again.

Thermosphere is the first layer ionosphere. Unlike the previously mentioned layers, the ionosphere is not distinguished by temperature. The ionosphere is an area of electrical nature that makes many types of radio communications possible. The ionosphere is divided into several layers, designated by the letters D, E, F1 and F2. These layers also have special names. The separation into layers is caused by several reasons, among which the most important is the unequal influence of the layers on the passage of radio waves. The lowest layer, D, mainly absorbs radio waves and thereby prevents their further propagation. The best studied layer E is located at an altitude of approximately 100 km above the earth's surface. It is also called the Kennelly-Heaviside layer after the names of the American and English scientists who simultaneously and independently discovered it. Layer E, like a giant mirror, reflects radio waves. Thanks to this layer, long radio waves travel further distances than would be expected if they propagated only in a straight line, without being reflected from the E layer. The F layer has similar properties. It is also called the Appleton layer. Together with the Kennelly-Heaviside layer, it reflects radio waves to terrestrial radio stations. Such reflection can occur at various angles. The Appleton layer is located at an altitude of about 240 km.

The outermost region of the atmosphere, the second layer of the ionosphere, is often called exosphere. This term refers to the existence of the outskirts of space near the Earth. It is difficult to determine exactly where the atmosphere ends and space begins, since with altitude the density of atmospheric gases gradually decreases and the atmosphere itself gradually turns into almost a vacuum, in which only individual molecules are found. Already at an altitude of approximately 320 km, the density of the atmosphere is so low that molecules can travel more than 1 km without colliding with each other. The outermost part of the atmosphere serves as its upper boundary, which is located at altitudes from 480 to 960 km.

More information about processes in the atmosphere can be found on the website “Earth Climate”

> Earth's atmosphere

Description Earth's atmosphere for children of all ages: what air is made of, the presence of gases, layers with photos, climate and weather of the third planet of the solar system.

For the little ones It is already known that the Earth is the only planet in our system that has a viable atmosphere. The gas blanket is not only rich in air, but also protects us from excessive heat and solar radiation. Important explain to the children that the system is designed incredibly well, because it allows the surface to warm up during the day and cool down at night, maintaining an acceptable balance.

Begin explanation for children It is possible from the fact that the globe of the earth's atmosphere extends over 480 km, but most of it is located 16 km from the surface. The higher the altitude, the lower the pressure. If we take sea level, then the pressure there is 1 kg per square centimeter. But at an altitude of 3 km, it will change - 0.7 kg per square centimeter. Of course, in such conditions it is more difficult to breathe ( children you could feel this if you ever went hiking in the mountains).

Composition of the Earth's air - explanation for children

Among the gases there are:

Nitrogen – 78%.
Oxygen – 21%.
Argon – 0.93%.
Carbon dioxide – 0.038%.
There is also water vapor and other gas impurities in small quantities.

Atmospheric layers of the Earth - explanation for children

Parents or teachers At school We should remind you that the earth's atmosphere is divided into 5 levels: exosphere, thermosphere, mesosphere, stratosphere and troposphere. With each layer, the atmosphere dissolves more and more until the gases finally disperse into space.

The troposphere is closest to the surface. With a thickness of 7-20 km, it makes up half of the earth's atmosphere. The closer to Earth, the more the air warms up. Almost all water vapor and dust are collected here. Children may not be surprised that clouds float at this level.

The stratosphere starts from the troposphere and rises 50 km above the surface. There is a lot of ozone here, which heats the atmosphere and protects from harmful solar radiation. The air is 1000 times thinner than above sea level and unusually dry. That is why airplanes feel great here.

Mesosphere: 50 km to 85 km above the surface. The peak is called the mesopause and is the coolest place in the earth's atmosphere (-90°C). It is very difficult to explore because jet planes cannot get there, and the orbital altitude of the satellites is too high. Scientists only know that this is where meteors burn up.

Thermosphere: 90 km and between 500-1000 km. The temperature reaches 1500°C. It is considered part of the earth's atmosphere, but it is important explain to the children that the air density here is so low that most of it is already perceived as outer space. In fact, this is where the space shuttles and the International Space Station are located. In addition, auroras are formed here. Charged cosmic particles come into contact with atoms and molecules of the thermosphere, transferring them to a higher energy level. Thanks to this, we see these photons of light in the form of the aurora.

The exosphere is the highest layer. An incredibly thin line of merging the atmosphere with space. Consists of widely scattered hydrogen and helium particles.

Earth's climate and weather - explanation for children

For the little ones need to explain that the Earth manages to support many living species thanks to a regional climate that is represented by extreme cold at the poles and tropical warmth at the equator. Children should know that regional climate is the weather that in a particular area remains unchanged for 30 years. Of course, sometimes it can change for a few hours, but for the most part it remains stable.

In addition, the global earth climate is distinguished - the average of the regional one. It has changed throughout human history. Today there is rapid warming. Scientists are sounding the alarm as greenhouse gases caused by human activity are trapping heat in the atmosphere, risking turning our planet into Venus.

The atmosphere extends upward for many hundreds of kilometers. Its upper limit, at an altitude of about 2000-3000 km, to a certain extent, it is conditional, since the gases that make it up, gradually becoming rarefied, pass into cosmic space. The chemical composition of the atmosphere, pressure, density, temperature and its other physical properties change with altitude. As mentioned earlier, the chemical composition of air up to a height of 100 km does not change significantly. Slightly higher, the atmosphere also consists mainly of nitrogen and oxygen. But at altitudes 100-110 km, Under the influence of ultraviolet radiation from the sun, oxygen molecules are split into atoms and atomic oxygen appears. Above 110-120 km almost all oxygen becomes atomic. Supposedly above 400-500 km The gases that make up the atmosphere are also in an atomic state.

Air pressure and density decrease rapidly with altitude. Although the atmosphere extends upward for hundreds of kilometers, the bulk of it is located in a rather thin layer adjacent to the surface of the earth in its lowest parts. So, in the layer between sea level and heights 5-6 km half the mass of the atmosphere is concentrated in the layer 0-16 km-90%, and in the layer 0-30 km- 99%. The same rapid decrease in air mass occurs above 30 km. If weight 1 m 3 air at the surface of the earth is 1033 g, then at a height of 20 km it is equal to 43 g, and at a height of 40 km only 4 years

At an altitude of 300-400 km and above, the air is so rarefied that during the day its density changes many times. Research has shown that this change in density is related to the position of the Sun. The highest air density is around noon, the lowest at night. This is partly explained by the fact that the upper layers of the atmosphere react to changes in the electromagnetic radiation of the Sun.

Air temperature also varies unequally with altitude. According to the nature of temperature changes with altitude, the atmosphere is divided into several spheres, between which there are transition layers, so-called pauses, where the temperature changes little with altitude.

Here are the names and main characteristics of the spheres and transition layers.

Let us present basic data on the physical properties of these spheres.

Troposphere. The physical properties of the troposphere are largely determined by the influence of the earth's surface, which is its lower boundary. The highest altitude of the troposphere is observed in the equatorial and tropical zones. Here it reaches 16-18 km and is subject to relatively little daily and seasonal changes. Over the polar and adjacent regions, the upper boundary of the troposphere lies on average at a level of 8-10 km. In middle latitudes it ranges from 6-8 to 14-16 km.

The vertical thickness of the troposphere depends significantly on the nature of atmospheric processes. Often during the day the upper boundary of the troposphere above a given point or area falls or rises by several kilometers. This is mainly due to changes in air temperature.

More than 4/5 of the mass of the earth's atmosphere and almost all the water vapor contained in it are concentrated in the troposphere. In addition, from the surface of the earth to the upper boundary of the troposphere, the temperature decreases by an average of 0.6° for every 100 m, or 6° per 1 km raising . This is explained by the fact that the air in the troposphere is heated and cooled primarily by the earth's surface.

In accordance with the influx of solar energy, the temperature decreases from the equator to the poles. Thus, the average air temperature at the surface of the earth at the equator reaches +26°, over the polar regions in winter -34°, -36°, and in summer about 0°. Thus, the temperature difference between the equator and the pole in winter is 60°, and in summer only 26°. True, such low temperatures in the Arctic in winter are observed only near the surface of the earth due to cooling of the air above the icy expanses.

In winter in Central Antarctica, the air temperature on the surface of the ice sheet is even lower. At Vostok station in August 1960, the lowest temperature on the globe was recorded -88.3°, and most often in Central Antarctica it is -45°, -50°.

With height, the temperature difference between the equator and the pole decreases. For example, at an altitude of 5 km at the equator the temperature reaches -2°, -4°, and at the same altitude in the Central Arctic -37°, -39° in winter and -19°, -20° in summer; therefore, the temperature difference in winter is 35-36°, and in summer 16-17°. In the southern hemisphere these differences are somewhat larger.

The energy of atmospheric circulation can be determined by equator-pole temperature contracts. Since the magnitude of temperature contrasts is greater in winter, atmospheric processes occur more intensely than in summer. This also explains the fact that the prevailing westerly winds in the troposphere in winter have higher speeds than in summer. In this case, the wind speed, as a rule, increases with height, reaching a maximum at the upper boundary of the troposphere. Horizontal transfer is accompanied by vertical movements of air and turbulent (disordered) movement. Due to the rise and fall of large volumes of air, clouds form and dissipate, precipitation occurs and ceases. The transition layer between the troposphere and the overlying sphere is tropopause. Above it lies the stratosphere.

Stratosphere extends from heights 8-17 to 50-55 km. It was discovered at the beginning of our century. In terms of physical properties, the stratosphere differs sharply from the troposphere in that the air temperature here, as a rule, increases by an average of 1 - 2 ° per kilometer of elevation and at the upper boundary, at an altitude of 50-55 km, even becomes positive. The increase in temperature in this area is caused by the presence of ozone (O 3), which is formed under the influence of ultraviolet radiation from the Sun. The ozone layer occupies almost the entire stratosphere. The stratosphere is very poor in water vapor. There are no violent processes of cloud formation and no precipitation.

More recently, it was assumed that the stratosphere is a relatively calm environment where air mixing does not occur, as in the troposphere. Therefore, it was believed that gases in the stratosphere are divided into layers in accordance with their specific gravities. Hence the name stratosphere (“stratus” - layered). It was also believed that the temperature in the stratosphere is formed under the influence of radiative equilibrium, i.e., when absorbed and reflected solar radiation is equal.

New data obtained from radiosondes and weather rockets have shown that the stratosphere, like the upper troposphere, experiences intense air circulation with large changes in temperature and wind. Here, as in the troposphere, the air experiences significant vertical movements and turbulent movements with strong horizontal air currents. All this is the result of a non-uniform temperature distribution.

The transition layer between the stratosphere and the overlying sphere is stratopause. However, before moving on to the characteristics of higher layers of the atmosphere, let us become familiar with the so-called ozonosphere, the boundaries of which approximately correspond to the boundaries of the stratosphere.

Ozone in the atmosphere. Ozone plays a large role in creating temperature regimes and air currents in the stratosphere. Ozone (O 3) is felt by us after a thunderstorm when we inhale clean air with a pleasant aftertaste. However, here we will not talk about this ozone formed after a thunderstorm, but about the ozone contained in the 10-60 layer km with a maximum at an altitude of 22-25 km. Ozone is formed under the influence of ultraviolet rays from the Sun and, although its total amount is small, plays an important role in the atmosphere. Ozone has the ability to absorb ultraviolet radiation from the Sun and thereby protects flora and fauna from its destructive effects. Even that insignificant fraction of ultraviolet rays that reaches the surface of the earth severely burns the body when a person is overly keen on sunbathing.

The amount of ozone varies over different parts of the Earth. There is more ozone in high latitudes, less in middle and low latitudes, and this amount varies depending on the changing seasons of the year. There is more ozone in spring, less in autumn. In addition, non-periodic fluctuations occur depending on the horizontal and vertical circulation of the atmosphere. Many atmospheric processes are closely related to ozone content, since it has a direct impact on the temperature field.

In winter, under polar night conditions, at high latitudes, radiation and cooling of the air occurs in the ozone layer. As a result, in the stratosphere of high latitudes (in the Arctic and Antarctic), a cold region is formed in winter, a stratospheric cyclonic vortex with large horizontal temperature and pressure gradients, causing westerly winds over the mid-latitudes of the globe.

In summer, under polar day conditions, at high latitudes, the ozone layer absorbs solar heat and warms the air. As a result of an increase in temperature in the stratosphere at high latitudes, a heat region and a stratospheric anticyclonic vortex are formed. Therefore, above the middle latitudes of the globe above 20 km In summer, easterly winds predominate in the stratosphere.

Mesosphere. Observations using meteorological rockets and other methods have established that the general increase in temperature observed in the stratosphere ends at altitudes of 50-55 km. Above this layer, the temperature decreases again and at the upper boundary of the mesosphere (about 80 km) reaches -75°, -90°. Then the temperature increases again with height.

It is interesting to note that the decrease in temperature with height characteristic of the mesosphere occurs differently at different latitudes and throughout the year. In low latitudes, the temperature drop occurs more slowly than in high latitudes: the average vertical temperature gradient for the mesosphere is respectively 0.23° - 0.31° per 100 m or 2.3°-3.1° per 1 km. In summer it is much larger than in winter. As the latest research in high latitudes has shown, the temperature at the upper boundary of the mesosphere in summer is several tens of degrees lower than in winter. In the upper mesosphere at an altitude of about 80 km In the mesopause layer, the decrease in temperature with height stops and its increase begins. Here, under the inversion layer at dusk or before sunrise in clear weather, shiny thin clouds are observed, illuminated by the sun below the horizon. Against the dark background of the sky they glow with a silvery-blue light. That's why these clouds are called noctilucent.

The nature of noctilucent clouds has not yet been sufficiently studied. For a long time it was believed that they consisted of volcanic dust. However, the absence of optical phenomena characteristic of real volcanic clouds led to the abandonment of this hypothesis. It was then suggested that noctilucent clouds were composed of cosmic dust. In recent years, a hypothesis has been proposed that these clouds are composed of ice crystals, like ordinary cirrus clouds. The level of noctilucent clouds is determined by the blocking layer due to temperature inversion during the transition from the mesosphere to the thermosphere at an altitude of about 80 km. Since the temperature in the sub-inversion layer reaches -80° and below, the most favorable conditions are created here for the condensation of water vapor, which enters here from the stratosphere as a result of vertical movement or by turbulent diffusion. Noctilucent clouds are usually observed in the summer, sometimes in very large numbers and for several months.

Observations of noctilucent clouds have established that in summer the winds at their level are highly variable. Wind speeds vary widely: from 50-100 to several hundred kilometers per hour.

Temperature at altitudes. A visual representation of the nature of the temperature distribution with height, between the earth's surface and altitudes of 90-100 km, in winter and summer in the northern hemisphere, is given by Figure 5. The surfaces separating the spheres are depicted here with thick dashed lines. At the very bottom, the troposphere is clearly visible with a characteristic decrease in temperature with height. Above the tropopause, in the stratosphere, on the contrary, the temperature generally increases with height and at altitudes of 50-55 km reaches + 10°, -10°. Let's pay attention to an important detail. In winter, in the stratosphere of high latitudes, the temperature above the tropopause drops from -60 to -75° and only above 30 km again increases to -15°. In summer, starting from the tropopause, the temperature rises with altitude by 50 km reaches + 10°. Above the stratopause, the temperature decreases again with height, and at a level of 80 km it does not exceed -70°, -90°.

From Figure 5 it follows that in the layer 10-40 km The air temperature in winter and summer at high latitudes is sharply different. In winter, under polar night conditions, the temperature here reaches -60°, -75°, and in summer a minimum of -45° is near the tropopause. Above the tropopause, the temperature increases at altitudes of 30-35 km is only -30°, -20°, which is caused by the heating of the air in the ozone layer under polar day conditions. It also follows from the figure that even in the same season and at the same level, the temperature is not the same. Their difference between different latitudes exceeds 20-30°. In this case, the heterogeneity is especially significant in the layer of low temperatures (18-30 km) and in the layer of maximum temperatures (50-60 km) in the stratosphere, as well as in the layer of low temperatures in the upper mesosphere (75-85km).

The average temperatures shown in Figure 5 are obtained from observational data in the northern hemisphere, however, judging by the available information, they can also be attributed to the southern hemisphere. Some differences exist mainly at high latitudes. Over Antarctica in winter, the air temperature in the troposphere and lower stratosphere is noticeably lower than over the Central Arctic.

Winds at heights. The seasonal distribution of temperature is determined by a rather complex system of air currents in the stratosphere and mesosphere.

Figure 6 shows a vertical section of the wind field in the atmosphere between the earth's surface and a height of 90 km winter and summer over the northern hemisphere. The isolines depict the average speeds of the prevailing wind (in m/sec). It follows from the figure that the wind regime in the stratosphere in winter and summer is sharply different. In winter, both the troposphere and stratosphere are dominated by westerly winds with maximum speeds of about

100 m/sec at an altitude of 60-65 km. In summer, westerly winds prevail only up to heights of 18-20 km. Higher up they become eastern, with maximum speeds up to 70 m/sec at an altitude of 55-60km.

In summer, above the mesosphere, the winds become westerly, and in winter - eastern.

Thermosphere. Above the mesosphere is the thermosphere, which is characterized by an increase in temperature With height. According to the data obtained, mainly with the help of rockets, it was established that in the thermosphere already at a level of 150 km air temperature reaches 220-240°, and at 200 km more than 500°. Above the temperature continues to rise and at the level of 500-600 km exceeds 1500°. Based on data obtained from the launches of artificial Earth satellites, it was found that in the upper thermosphere the temperature reaches about 2000° and fluctuates significantly during the day. The question arises as to how to explain such high temperatures in the high layers of the atmosphere. Recall that the temperature of a gas is a measure of the average speed of movement of molecules. In the lower, densest part of the atmosphere, the molecules of the gases that make up the air often collide with each other when moving and instantly transfer kinetic energy to each other. Therefore, the kinetic energy in a dense medium is on average the same. In high layers, where the air density is very low, collisions between molecules located at large distances occur less frequently. When energy is absorbed, the speed of molecules changes greatly between collisions; in addition, molecules of lighter gases move at higher speeds than molecules of heavy gases. As a result, the temperature of the gases may be different.

In rarefied gases there are relatively few molecules of very small sizes (light gases). If they move at high speeds, then the temperature in a given volume of air will be high. In the thermosphere, every cubic centimeter of air contains tens and hundreds of thousands of molecules of various gases, while at the surface of the earth there are about hundreds of millions of billions of them. Therefore, excessively high temperatures in the high layers of the atmosphere, showing the speed of movement of molecules in this very loose environment, cannot cause even slight heating of the body located here. Just as a person does not feel high temperature under the dazzling light of electric lamps, although the filaments in a rarefied environment instantly heat up to several thousand degrees.

In the lower thermosphere and mesosphere, the main part of meteor showers burns up before reaching the earth's surface.

Available information about atmospheric layers above 60-80 km are still insufficient for final conclusions about the structure, regime and processes developing in them. However, it is known that in the upper mesosphere and lower thermosphere the temperature regime is created as a result of the transformation of molecular oxygen (O 2) into atomic oxygen (O), which occurs under the influence of ultraviolet solar radiation. In the thermosphere, the temperature regime is greatly influenced by corpuscular, x-ray and. ultraviolet radiation from the sun. Here, even during the day, there are sharp changes in temperature and wind.

Ionization of the atmosphere. The most interesting feature of the atmosphere is above 60-80 km is hers ionization, i.e., the process of formation of a huge number of electrically charged particles - ions. Since the ionization of gases is characteristic of the lower thermosphere, it is also called the ionosphere.

Gases in the ionosphere are mostly in an atomic state. Under the influence of ultraviolet and corpuscular radiation from the Sun, which have high energy, the process of splitting off electrons from neutral atoms and air molecules occurs. Such atoms and molecules that have lost one or more electrons become positively charged, and the free electron can rejoin a neutral atom or molecule and endow it with its negative charge. Such positively and negatively charged atoms and molecules are called ions, and gases - ionized, i.e., having received an electric charge. At higher concentrations of ions, gases become electrically conductive.

The ionization process occurs most intensively in thick layers limited by heights of 60-80 and 220-400 km. In these layers there are optimal conditions for ionization. Here, the air density is noticeably greater than in the upper atmosphere, and the supply of ultraviolet and corpuscular radiation from the Sun is sufficient for the ionization process.

The discovery of the ionosphere is one of the important and brilliant achievements of science. After all, a distinctive feature of the ionosphere is its influence on the propagation of radio waves. In the ionized layers, radio waves are reflected, and therefore long-distance radio communication becomes possible. Charged atoms-ions reflect short radio waves, and they return to the earth's surface again, but at a considerable distance from the place of radio transmission. Obviously, short radio waves make this path several times, and thus long-distance radio communication is ensured. If it were not for the ionosphere, then it would be necessary to build expensive radio relay lines to transmit radio signals over long distances.

However, it is known that sometimes radio communications on short waves are disrupted. This occurs as a result of chromospheric flares on the Sun, due to which the ultraviolet radiation of the Sun sharply increases, leading to strong disturbances of the ionosphere and the Earth's magnetic field - magnetic storms. During magnetic storms, radio communications are disrupted, since the movement of charged particles depends on the magnetic field. During magnetic storms, the ionosphere reflects radio waves worse or transmits them into space. Mainly with changes in solar activity, accompanied by increased ultraviolet radiation, the electron density of the ionosphere and the absorption of radio waves during the daytime increase, leading to disruption of short-wave radio communications.

According to new research, in a powerful ionized layer there are zones where the concentration of free electrons reaches a slightly higher concentration than in neighboring layers. Four such zones are known, which are located at altitudes of about 60-80, 100-120, 180-200 and 300-400 km and are designated by letters D, E, F 1 And F 2 . With increasing radiation from the Sun, charged particles (corpuscles) under the influence of the Earth's magnetic field are deflected towards high latitudes. Upon entering the atmosphere, the corpuscles increase the ionization of gases so much that they begin to glow. This is how they arise auroras- in the form of beautiful multicolored arcs that light up in the night sky mainly in the high latitudes of the Earth. Auroras are accompanied by strong magnetic storms. In such cases, auroras become visible in mid-latitudes, and in rare cases even in the tropical zone. For example, the intense aurora observed on January 21-22, 1957, was visible in almost all southern regions of our country.

By photographing auroras from two points located at a distance of several tens of kilometers, the height of the auroras is determined with great accuracy. Usually auroras are located at an altitude of about 100 km, They are often found at an altitude of several hundred kilometers, and sometimes at a level of about 1000 km. Although the nature of the auroras has been clarified, there are still many unresolved questions related to this phenomenon. The reasons for the diversity of forms of auroras are still unknown.

According to the third Soviet satellite, between altitudes 200 and 1000 km During the day, positive ions of split molecular oxygen, i.e., atomic oxygen (O), predominate. Soviet scientists are exploring the ionosphere using artificial satellites of the Cosmos series. American scientists also study the ionosphere using satellites.

The surface separating the thermosphere from the exosphere fluctuates depending on changes in solar activity and other factors. Vertically, these fluctuations reach 100-200 km and more.

Exosphere (scattering sphere) - the uppermost part of the atmosphere, located above 800 km. It has been little studied. According to observational data and theoretical calculations, the temperature in the exosphere increases with altitude, presumably up to 2000°. Unlike the lower ionosphere, in the exosphere the gases are so rarefied that their particles, moving at enormous speeds, almost never meet each other.

Until relatively recently, it was assumed that the conventional boundary of the atmosphere is at an altitude of about 1000 km. However, based on the braking of artificial Earth satellites, it has been established that at altitudes of 700-800 km in 1 cm 3 contains up to 160 thousand positive ions of atomic oxygen and nitrogen. This suggests that the charged layers of the atmosphere extend into space over a much greater distance.

At high temperatures at the conventional boundary of the atmosphere, the speeds of gas particles reach approximately 12 km/sec. At these speeds, gases gradually escape from the region of gravity into interplanetary space. This happens over a long period of time. For example, particles of hydrogen and helium are removed into interplanetary space over several years.

In the study of high layers of the atmosphere, rich data was obtained both from satellites of the Cosmos and Electron series, and from geophysical rockets and space stations Mars-1, Luna-4, etc. Direct observations of astronauts also turned out to be valuable. Thus, according to photographs taken in space by V. Nikolaeva-Tereshkova, it was established that at an altitude of 19 km There is a dust layer from the Earth. This was confirmed by data obtained by the crew of the Voskhod spacecraft. Apparently, there is a close connection between the dust layer and the so-called pearly clouds, sometimes observed at altitudes of about 20-30km.

From the atmosphere to outer space. Previous assumptions that beyond the Earth's atmosphere, in the interplanetary

space, gases are very rarefied and the concentration of particles does not exceed several units in 1 cm 3, didn't come true. Research has shown that near-Earth space is filled with charged particles. On this basis, a hypothesis was put forward about the existence of zones around the Earth with a noticeably increased content of charged particles, i.e. radiation belts- internal and external. New data helped clarify things. It turned out that there are also charged particles between the inner and outer radiation belts. Their number varies depending on geomagnetic and solar activity. Thus, according to the new assumption, instead of radiation belts, there are radiation zones without clearly defined boundaries. The boundaries of radiation zones change depending on solar activity. When it intensifies, that is, when spots and jets of gas appear on the Sun, ejected over hundreds of thousands of kilometers, the flow of cosmic particles increases, which feed the Earth's radiation zones.

Radiation zones are dangerous for people flying on spacecraft. Therefore, before a flight into space, the state and position of radiation zones are determined, and the orbit of the spacecraft is chosen so that it passes outside areas of increased radiation. However, the high layers of the atmosphere, as well as outer space close to the Earth, have still been little explored.

The study of the high layers of the atmosphere and near-Earth space uses rich data obtained from Cosmos satellites and space stations.

The high layers of the atmosphere are the least studied. However, modern methods of its research allow us to hope that in the coming years people will know many details of the structure of the atmosphere at the bottom of which they live.

In conclusion, we present a schematic vertical section of the atmosphere (Fig. 7). Here, altitudes in kilometers and air pressure in millimeters are plotted vertically, and temperature is plotted horizontally. The solid curve shows the change in air temperature with height. At the corresponding altitudes, the most important phenomena observed in the atmosphere are noted, as well as the maximum altitudes reached by radiosondes and other means of sensing the atmosphere.