Temperature in different layers of the atmosphere. The structure of the atmosphere

Atmospheric air consists of nitrogen (77.99%), oxygen (21%), inert gases (1%) and carbon dioxide (0.01%). The share of carbon dioxide increases over time due to the fact that fuel combustion products are released into the atmosphere, and, in addition, the area of forests that absorb carbon dioxide and release oxygen decreases.

The atmosphere also contains a small amount of ozone, which is concentrated at an altitude of about 25-30 km and forms the so-called ozone layer. This layer creates a barrier to solar ultraviolet radiation, which is dangerous to living organisms on Earth.

In addition, the atmosphere contains water vapor and various impurities - dust particles, volcanic ash, soot, etc. The concentration of impurities is higher near the surface of the earth and in certain areas: above large cities, deserts.

Troposphere- lower, it contains most of the air and. The height of this layer varies: from 8-10 km near the tropics to 16-18 near the equator. in the troposphere it decreases with rise: by 6°C for every kilometer. The weather is formed in the troposphere, winds, precipitation, clouds, cyclones and anticyclones are formed.

The next layer of the atmosphere is stratosphere. The air in it is much more rarefied, and there is much less water vapor in it. The temperature in the lower part of the stratosphere is -60 - -80°C and falls with increasing altitude. It is in the stratosphere that the ozone layer is located. The stratosphere is characterized by high wind speeds (up to 80-100 m/sec).

Mesosphere- the middle layer of the atmosphere, lying above the stratosphere at altitudes from 50 to S0-S5 km. The mesosphere is characterized by a decrease in average temperature with height from 0°C at the lower boundary to -90°C at the upper boundary. Near the upper boundary of the mesosphere, noctilucent clouds are observed, illuminated by the sun at night. The air pressure at the upper boundary of the mesosphere is 200 times less than at the earth's surface.

Thermosphere- located above the mesosphere, at altitudes from SO to 400-500 km, in it the temperature first slowly and then quickly begins to rise again. The reason is the absorption of ultraviolet radiation from the Sun at altitudes of 150-300 km. In the thermosphere, the temperature continuously increases to an altitude of about 400 km, where it reaches 700 - 1500 ° C (depending on solar activity). Under the influence of ultraviolet, X-ray and cosmic radiation, ionization of the air (“auroras”) also occurs. The main regions of the ionosphere lie within the thermosphere.

Exosphere- the outer, most rarefied layer of the atmosphere, it begins at altitudes of 450-000 km, and its upper boundary is located at a distance of several thousand km from the earth’s surface, where the concentration of particles becomes the same as in interplanetary space. The exosphere consists of ionized gas (plasma); the lower and middle parts of the exosphere mainly consist of oxygen and nitrogen; With increasing altitude, the relative concentration of light gases, especially ionized hydrogen, rapidly increases. The temperature in the exosphere is 1300-3000° C; it grows weakly with height. The Earth's radiation belts are mainly located in the exosphere.

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%.

In addition to the gases indicated in the table, the atmosphere contains Cl 2, SO 2, NH 3, CO, O 3, NO 2, hydrocarbons, HCl, HBr, vapors, I 2, Br 2, as well as many other gases in minor amounts quantities. The troposphere constantly contains a large amount of suspended solid and liquid particles (aerosol). The rarest gas in the Earth's atmosphere is radon (Rn).

The structure of the atmosphere

Atmospheric boundary layer

The lower layer of the atmosphere adjacent to the Earth's surface (1-2 km thick) in which the influence of this surface directly affects its dynamics.

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 the total water vapor present in the atmosphere. Turbulence and convection are highly developed in the troposphere, clouds appear, and cyclones and anticyclones develop. Temperature decreases with increasing altitude with an average vertical gradient of 0.65°/100 m

Tropopause

The transition layer from the troposphere to the stratosphere, a layer of the atmosphere in which the decrease in temperature with height stops.

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 temperature in the 25-40 km layer from −56.5 to 0.8 ° (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.

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

The 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. According to the FAI definition, the Karman line is located at an altitude of 100 km above sea level.

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 1226.85 C, after which it remains almost constant to high altitudes. Under the influence of solar radiation and cosmic radiation, ionization of the air (“ auroras”) occurs - the main regions of the ionosphere lie inside the thermosphere. At altitudes above 300 km, atomic oxygen predominates. The upper limit of the thermosphere is largely determined by the current activity of the Sun. During periods of low activity - for example, in 2008-2009 - there is a noticeable decrease in the size of this layer.

Thermopause

The region of the atmosphere adjacent above the thermosphere. In this region, the absorption of solar radiation is negligible and the temperature does not actually change with altitude.

Exosphere (scattering sphere)

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 ~150 °C. Above 200 km, significant fluctuations in temperature and gas density in time and space are observed.

At an altitude of about 2000-3500 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.

Review

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 electrical properties in the atmosphere, they distinguish neutrosphere And ionosphere .

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 the homosphere. The boundary between these layers is called the turbopause, it lies at an altitude of about 120 km.

Other properties of the atmosphere and effects on the human body

Already at an altitude of 5 km above sea level, an untrained person begins to experience 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 9 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.

In rarefied layers of air, sound propagation is 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, the concepts of the M number and the sound barrier, familiar to every pilot, lose their meaning: there passes the conventional Karman line, beyond which the region of purely ballistic flight begins, 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 (that is, 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 this altitude, as in space generally, the only way to transfer heat is thermal radiation.

History of atmospheric formation

According to the most common theory, the Earth's atmosphere has had three different compositions throughout its history. Initially, it consisted of light gases (hydrogen and helium) captured from interplanetary space. This is the so-called primary atmosphere. 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. 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 nitrogen N2 is due to the oxidation of the ammonia-hydrogen atmosphere by molecular oxygen O2, which began to come from the surface of the planet as a result of photosynthesis, starting 3 billion years ago. Nitrogen 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 small quantities in the industrial production of nitrogen fertilizers. Cyanobacteria (blue-green algae) and nodule bacteria, which form rhizobial symbiosis with leguminous plants, which can be effective green manures - plants that do not deplete, but enrich the soil with natural fertilizers, can oxidize it with low energy consumption and convert it into a biologically active form.

Oxygen

The composition of the atmosphere began to change radically with the appearance of living organisms on Earth, as a result of photosynthesis, accompanied by the release of oxygen and the absorption of carbon dioxide. Initially, oxygen was spent on the oxidation of reduced compounds - ammonia, hydrocarbons, ferrous form of iron 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 the atmosphere, lithosphere and biosphere, this event was called the Oxygen Catastrophe.

Noble gases

Air pollution

Recently, humans have begun to influence the evolution of the atmosphere. The result of human activity has been a constant 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 200-300 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, SO2). Sulfur dioxide is oxidized by atmospheric oxygen to SO 3, and nitrogen oxide to NO 2 in the upper layers of the atmosphere, which in turn interact with water vapor, and the resulting sulfuric acid H 2 SO 4 and nitric acid HNO 3 fall to the surface of the Earth in the form so-called acid rain. The use of 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.

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Notes

M. I. Budyko, K. Ya. Kondratiev Atmosphere of the Earth // Great Soviet Encyclopedia. 3rd ed. / Ch. ed. A. M. Prokhorov. - M.: Soviet Encyclopedia, 1970. - T. 2. Angola - Barzas. - pp. 380-384.
- article from the Geological Encyclopedia
Gribbin, John. Science. A History (1543-2001). - L.: Penguin Books, 2003. - 648 p. - ISBN 978-0-140-29741-6.
Tans, Pieter. Globally averaged marine surface annual mean data. NOAA/ESRL. Retrieved February 19, 2014.(English) (as of 2013)
IPCC (English) (as of 1998).
S. P. Khromov Air humidity // Great Soviet Encyclopedia. 3rd ed. / Ch. ed. A. M. Prokhorov. - M.: Soviet Encyclopedia, 1971. - T. 5. Veshin - Gazli. - P. 149.
(English) SpaceDaily, 07/16/2010

Literature

V. V. Parin, F. P. Kosmolinsky, B. A. Dushkov“Space biology and medicine” (2nd edition, revised and expanded), M.: “Prosveshcheniye”, 1975, 223 pp.
N. V. Gusakova“Environmental Chemistry”, Rostov-on-Don: Phoenix, 2004, 192 with ISBN 5-222-05386-5
Sokolov V. A. Geochemistry of natural gases, M., 1971;
McEwen M., Phillips L. Atmospheric Chemistry, M., 1978;
Wark K., Warner S. Air pollution. Sources and control, trans. from English, M.. 1980;
Monitoring of background pollution of natural environments. V. 1, L., 1982.

Links

// December 17, 2013, FOBOS Center



History of the Earth

Physical properties of the Earth

Shells of the Earth

Geography and geology

Environment

see also

Excerpt characterizing the Earth's Atmosphere

When Pierre approached them, he noticed that Vera was in a smug rapture of conversation, Prince Andrei (which rarely happened to him) seemed embarrassed.
– What do you think? – Vera said with a subtle smile. “You, prince, are so insightful and so immediately understand the character of people.” What do you think about Natalie, can she be constant in her affections, can she, like other women (Vera meant herself), love a person once and remain faithful to him forever? This is what I consider true love. What do you think, prince?
“I know your sister too little,” answered Prince Andrei with a mocking smile, under which he wanted to hide his embarrassment, “to resolve such a delicate question; and then I noticed that the less I like a woman, the more constant she is,” he added and looked at Pierre, who came up to them at that time.
- Yes, it’s true, prince; in our time,” Vera continued (mentioning our time, as narrow-minded people generally like to mention, believing that they have found and appreciated the features of our time and that the properties of people change over time), in our time a girl has so much freedom that le plaisir d"etre courtisee [the pleasure of having admirers] often drowns out the true feeling in her. Et Nathalie, il faut l"avouer, y est tres sensible. [And Natalya, I must admit, is very sensitive to this.] The return to Natalie again made Prince Andrei frown unpleasantly; he wanted to get up, but Vera continued with an even more refined smile.
“I think no one was courtisee [the object of courtship] like her,” said Vera; - but never, until very recently, did she seriously like anyone. “You know, Count,” she turned to Pierre, “even our dear cousin Boris, who was, entre nous [between us], very, very dans le pays du tendre... [in the land of tenderness...]
Prince Andrei frowned and remained silent.
– You’re friends with Boris, aren’t you? - Vera told him.
- Yes, I know him…
– Did he tell you correctly about his childhood love for Natasha?
– Was there childhood love? - Prince Andrei suddenly asked, blushing unexpectedly.
- Yes. Vous savez entre cousin et cousine cette intimate mene quelquefois a l"amour: le cousinage est un dangereux voisinage, N"est ce pas? [You know, between a cousin and sister, this closeness sometimes leads to love. Such kinship is a dangerous neighborhood. Is not it?]
“Oh, without a doubt,” said Prince Andrei, and suddenly, unnaturally animated, he began joking with Pierre about how he should be careful in his treatment of his 50-year-old Moscow cousins, and in the middle of the joking conversation he stood up and, taking under Pierre's arm and took him aside.
- Well? - said Pierre, looking with surprise at the strange animation of his friend and noticing the look that he cast at Natasha as he stood up.
“I need, I need to talk to you,” said Prince Andrei. – You know our women’s gloves (he was talking about those Masonic gloves that were given to a newly elected brother to give to his beloved woman). “I... But no, I’ll talk to you later...” And with a strange sparkle in his eyes and anxiety in his movements, Prince Andrei approached Natasha and sat down next to her. Pierre saw Prince Andrei ask her something, and she flushed and answered him.
But at this time Berg approached Pierre, urgently asking him to take part in the dispute between the general and the colonel about Spanish affairs.
Berg was pleased and happy. The smile of joy did not leave his face. The evening was very good and exactly like other evenings he had seen. Everything was similar. And ladies', delicate conversations, and cards, and a general at cards, raising his voice, and a samovar, and cookies; but one thing was still missing, something that he always saw at the evenings, which he wanted to imitate.
There was a lack of loud conversation between men and an argument about something important and smart. The general started this conversation and Berg attracted Pierre to him.

The next day, Prince Andrei went to the Rostovs for dinner, as Count Ilya Andreich called him, and spent the whole day with them.
Everyone in the house felt for whom Prince Andrei was traveling, and he, without hiding, tried to be with Natasha all day. Not only in Natasha’s frightened, but happy and enthusiastic soul, but in the whole house one could feel the fear of something important that was about to happen. The Countess looked at Prince Andrei with sad and seriously stern eyes when he spoke to Natasha, and timidly and feignedly began some insignificant conversation as soon as he looked back at her. Sonya was afraid to leave Natasha and was afraid to be a hindrance when she was with them. Natasha turned pale with fear of anticipation when she remained alone with him for minutes. Prince Andrei amazed her with his timidity. She felt that he needed to tell her something, but that he could not bring himself to do so.
When Prince Andrey left in the evening, the Countess came up to Natasha and said in a whisper:
- Well?
“Mom, for God’s sake don’t ask me anything now.” “You can’t say that,” Natasha said.
But despite this, that evening Natasha, sometimes excited, sometimes frightened, with fixed eyes, lay for a long time in her mother’s bed. Either she told her how he praised her, then how he said that he would go abroad, then how he asked where they would live this summer, then how he asked her about Boris.
- But this, this... has never happened to me! - she said. “Only I’m scared in front of him, I’m always scared in front of him, what does that mean?” That means it's real, right? Mom, are you sleeping?
“No, my soul, I’m scared myself,” answered the mother. - Go.
- I won’t sleep anyway. What nonsense is it to sleep? Mom, mom, this has never happened to me! - she said with surprise and fear at the feeling that she recognized in herself. – And could we think!...
It seemed to Natasha that even when she first saw Prince Andrey in Otradnoye, she fell in love with him. She seemed to be frightened by this strange, unexpected happiness, that the one whom she had chosen back then (she was firmly convinced of this), that the same one had now met her again, and, it seemed, was not indifferent to her. “And he had to come to St. Petersburg on purpose now that we are here. And we had to meet at this ball. It's all fate. It is clear that this is fate, that all this was leading to this. Even then, as soon as I saw him, I felt something special.”
- What else did he tell you? What verses are these? Read... - the mother said thoughtfully, asking about the poems that Prince Andrei wrote in Natasha’s album.
“Mom, isn’t it a shame that he’s a widower?”
- That's enough, Natasha. Pray to God. Les Marieiages se font dans les cieux. [Marriages are made in heaven.]
- Darling, mother, how I love you, how good it makes me feel! – Natasha shouted, crying tears of happiness and excitement and hugging her mother.
At the same time, Prince Andrei was sitting with Pierre and telling him about his love for Natasha and his firm intention to marry her.

On this day, Countess Elena Vasilyevna had a reception, there was a French envoy, there was a prince, who had recently become a frequent visitor to the countess’s house, and many brilliant ladies and men. Pierre was downstairs, walked through the halls, and amazed all the guests with his concentrated, absent-minded and gloomy appearance.
Since the time of the ball, Pierre had felt the approaching attacks of hypochondria and with desperate effort tried to fight against them. From the time the prince became close to his wife, Pierre was unexpectedly granted a chamberlain, and from that time on he began to feel heaviness and shame in large society, and more often the old gloomy thoughts about the futility of everything human began to come to him. At the same time, the feeling he noticed between Natasha, whom he protected, and Prince Andrei, the contrast between his position and the position of his friend, further intensified this gloomy mood. He equally tried to avoid thoughts about his wife and about Natasha and Prince Andrei. Again everything seemed insignificant to him in comparison with eternity, again the question presented itself: “why?” And he forced himself to work day and night on Masonic works, hoping to ward off the approach of the evil spirit. Pierre, at 12 o'clock, having left the countess's chambers, was sitting upstairs in a smoky, low room, in a worn dressing gown in front of the table, copying out authentic Scottish acts, when someone entered his room. It was Prince Andrei.
“Oh, it’s you,” said Pierre with an absent-minded and dissatisfied look. “And I’m working,” he said, pointing to a notebook with that look of salvation from the hardships of life with which unhappy people look at their work.
Prince Andrei, with a radiant, enthusiastic face and renewed life, stopped in front of Pierre and, not noticing his sad face, smiled at him with the egoism of happiness.
“Well, my soul,” he said, “yesterday I wanted to tell you and today I came to you for this.” I've never experienced anything like it. I'm in love, my friend.
Pierre suddenly sighed heavily and collapsed with his heavy body on the sofa, next to Prince Andrei.
- To Natasha Rostova, right? - he said.
- Yes, yes, who? I would never believe it, but this feeling is stronger than me. Yesterday I suffered, I suffered, but I wouldn’t give up this torment for anything in the world. I haven't lived before. Now only I live, but I cannot live without her. But can she love me?... I'm too old for her... What aren't you saying?...
- I? I? “What did I tell you,” Pierre suddenly said, getting up and starting to walk around the room. - I always thought this... This girl is such a treasure, such... This is a rare girl... Dear friend, I ask you, don’t get smart, don’t doubt, get married, get married and get married... And I’m sure that there will be no happier person than you.
- But she!
- She loves you.
“Don’t talk nonsense...” said Prince Andrei, smiling and looking into Pierre’s eyes.
“He loves me, I know,” Pierre shouted angrily.
“No, listen,” said Prince Andrei, stopping him by the hand. – Do you know what situation I’m in? I need to tell everything to someone.
“Well, well, say, I’m very glad,” said Pierre, and indeed his face changed, the wrinkles smoothed out, and he joyfully listened to Prince Andrei. Prince Andrei seemed and was a completely different, new person. Where was his melancholy, his contempt for life, his disappointment? Pierre was the only person to whom he dared to speak; but he expressed to him everything that was in his soul. Either he easily and boldly made plans for a long future, talked about how he could not sacrifice his happiness for the whim of his father, how he would force his father to agree to this marriage and love her or do without his consent, then he was surprised how something strange, alien, independent of him, influenced by the feeling that possessed him.
“I wouldn’t believe anyone who told me that I could love like that,” said Prince Andrei. “This is not at all the feeling that I had before.” The whole world is divided for me into two halves: one - she and there is all the happiness of hope, light; the other half is everything where she is not there, there is all despondency and darkness...
“Darkness and gloom,” Pierre repeated, “yes, yes, I understand that.”
– I can’t help but love the world, it’s not my fault. And I'm very happy. You understand me? I know you're happy for me.
“Yes, yes,” Pierre confirmed, looking at his friend with tender and sad eyes. The brighter the fate of Prince Andrei seemed to him, the darker his own seemed.

To get married, the consent of the father was needed, and for this, the next day, Prince Andrei went to his father.
The father, with outward calm but inner anger, accepted his son’s message. He could not understand that anyone would want to change life, to introduce something new into it, when life was already ending for him. “If only they would let me live the way I want, and then we would do what we wanted,” the old man said to himself. With his son, however, he used the diplomacy that he used on important occasions. Taking a calm tone, he discussed the whole matter.
Firstly, the marriage was not brilliant in terms of kinship, wealth and nobility. Secondly, Prince Andrei was not in his first youth and was in poor health (the old man was especially careful about this), and she was very young. Thirdly, there was a son whom it was a pity to give to the girl. Fourthly, finally,” said the father, looking mockingly at his son, “I ask you, postpone the matter for a year, go abroad, get treatment, find, as you want, a German for Prince Nikolai, and then, if it’s love, passion, stubbornness, whatever you want, so great, then get married.
“And this is my last word, you know, my last...” the prince finished in a tone that showed that nothing would force him to change his decision.
Prince Andrei clearly saw that the old man hoped that the feeling of him or his future bride would not withstand the test of the year, or that he himself, the old prince, would die by this time, and decided to fulfill his father’s will: to propose and postpone the wedding for a year.
Three weeks after his last evening with the Rostovs, Prince Andrei returned to St. Petersburg.

The next day after her explanation with her mother, Natasha waited the whole day for Bolkonsky, but he did not come. The next, third day the same thing happened. Pierre also did not come, and Natasha, not knowing that Prince Andrei had gone to his father, could not explain his absence.
Three weeks passed like this. Natasha did not want to go anywhere and, like a shadow, idle and sad, she walked from room to room, cried secretly from everyone in the evening and did not appear to her mother in the evenings. She was constantly blushing and irritated. It seemed to her that everyone knew about her disappointment, laughed and felt sorry for her. With all the strength of her inner grief, this vain grief intensified her misfortune.
One day she came to the countess, wanted to tell her something, and suddenly began to cry. Her tears were the tears of an offended child who himself does not know why he is being punished.
The Countess began to calm Natasha down. Natasha, who had been listening at first to her mother’s words, suddenly interrupted her:
- Stop it, mom, I don’t think, and I don’t want to think! So, I traveled and stopped, and stopped...
Her voice trembled, she almost cried, but she recovered and calmly continued: “And I don’t want to get married at all.” And I'm afraid of him; I have now completely, completely calmed down...
The next day after this conversation, Natasha put on that old dress, which she was especially famous for the cheerfulness it brought in the morning, and in the morning she began her old way of life, from which she had fallen behind after the ball. After drinking tea, she went to the hall, which she especially loved for its strong resonance, and began to sing her solfeges (singing exercises). Having finished the first lesson, she stopped in the middle of the hall and repeated one musical phrase that she especially liked. She listened joyfully to the (as if unexpected for her) charm with which these shimmering sounds filled the entire emptiness of the hall and slowly froze, and she suddenly felt cheerful. “It’s good to think about it so much,” she said to herself and began to walk back and forth around the hall, not walking with simple steps on the ringing parquet floor, but at every step shifting from heel (she was wearing her new, favorite shoes) to toe, and just as joyfully as I listen to the sounds of my own voice, listening to this measured clatter of a heel and the creaking of a sock. Passing by the mirror, she looked into it. - "Here I am!" as if the expression on her face when she saw herself spoke. - “Well, that’s good. And I don’t need anyone.”
The footman wanted to enter to clean something in the hall, but she did not let him in, again closing the door behind him, and continued her walk. This morning she returned again to her favorite state of self-love and admiration for herself. - “What a charm this Natasha is!” she said again to herself in the words of some third, collective, male person. “She’s good, she has a voice, she’s young, and she doesn’t bother anyone, just leave her alone.” But no matter how much they left her alone, she could no longer be calm and she immediately felt it.
The entrance door opened in the hallway, and someone asked: “Are you at home?” and someone's steps were heard. Natasha looked in the mirror, but she did not see herself. She listened to sounds in the hall. When she saw herself, her face was pale. It was he. She knew this for sure, although she barely heard the sound of his voice from the closed doors.
Natasha, pale and frightened, ran into the living room.
- Mom, Bolkonsky has arrived! - she said. - Mom, this is terrible, this is unbearable! – I don’t want... to suffer! What should I do?…
Before the countess even had time to answer her, Prince Andrei entered the living room with an anxious and serious face. As soon as he saw Natasha, his face lit up. He kissed the hand of the Countess and Natasha and sat down near the sofa.
“We haven’t had the pleasure for a long time...” the countess began, but Prince Andrei interrupted her, answering her question and obviously in a hurry to say what he needed.
“I wasn’t with you all this time because I was with my father: I needed to talk to him about a very important matter.” “I just returned last night,” he said, looking at Natasha. “I need to talk to you, Countess,” he added after a moment of silence.
The Countess, sighing heavily, lowered her eyes.
“I am at your service,” she said.
Natasha knew that she had to leave, but she could not do it: something was squeezing her throat, and she looked discourteously, directly, with open eyes at Prince Andrei.
"Now? This minute!... No, this can’t be!” she thought.
He looked at her again, and this look convinced her that she was not mistaken. “Yes, now, this very minute, her fate was being decided.”
“Come, Natasha, I’ll call you,” the countess said in a whisper.
Natasha looked at Prince Andrei and her mother with frightened, pleading eyes, and left.
“I came, Countess, to ask for your daughter’s hand in marriage,” said Prince Andrei. The countess's face flushed, but she said nothing.
“Your proposal...” the countess began sedately. “He was silent, looking into her eyes. – Your offer... (she was embarrassed) we are pleased, and... I accept your offer, I’m glad. And my husband... I hope... but it will depend on her...
“I’ll tell her when I have your consent... do you give it to me?” - said Prince Andrei.
“Yes,” said the countess and extended her hand to him and, with a mixed feeling of aloofness and tenderness, pressed her lips to his forehead as he leaned over her hand. She wanted to love him like a son; but she felt that he was a stranger and a terrible person for her. “I’m sure my husband will agree,” said the countess, “but your father...
“My father, to whom I told my plans, made it an indispensable condition of consent that the wedding should take place no earlier than a year. And this is what I wanted to tell you,” said Prince Andrei.
– It’s true that Natasha is still young, but for so long.
“It couldn’t be otherwise,” said Prince Andrei with a sigh.
“I will send it to you,” said the countess and left the room.
“Lord, have mercy on us,” she repeated, looking for her daughter. Sonya said that Natasha is in the bedroom. Natasha sat on her bed, pale, with dry eyes, looking at the images and, quickly crossing herself, whispering something. Seeing her mother, she jumped up and rushed to her.
- What? Mom?... What?
- Go, go to him. “He asks for your hand,” the countess said coldly, as it seemed to Natasha... “Come... come,” the mother said with sadness and reproach after her fleeing daughter, and sighed heavily.
Natasha did not remember how she entered the living room. Entering the door and seeing him, she stopped. “Has this stranger really become everything to me now?” she asked herself and instantly answered: “Yes, that’s it: he alone is now dearer to me than everything in the world.” Prince Andrei approached her, lowering his eyes.
“I loved you from the moment I saw you.” Can I hope?
He looked at her, and the serious passion in her expression struck him. Her face said: “Why ask? Why doubt something you can’t help but know? Why talk when you can’t express in words what you feel.”
She approached him and stopped. He took her hand and kissed it.
- Do you love me?
“Yes, yes,” Natasha said as if with annoyance, sighed loudly, and another time, more and more often, and began to sob.
- About what? What's wrong with you?
“Oh, I’m so happy,” she answered, smiled through her tears, leaned closer to him, thought for a second, as if asking herself if this was possible, and kissed him.
Prince Andrei held her hands, looked into her eyes, and did not find in his soul the same love for her. Something suddenly turned in his soul: there was no former poetic and mysterious charm of desire, but there was pity for her feminine and childish weakness, there was fear of her devotion and gullibility, a heavy and at the same time joyful consciousness of the duty that forever connected him with her. The real feeling, although it was not as light and poetic as the previous one, was more serious and stronger.

Changing the earth's surface. No less important was the activity of the wind, which carried small fractions of rocks over long distances. Temperature fluctuations and other atmospheric factors significantly influenced the destruction of rocks. Along with this, A. protects the Earth's surface from the destructive effects of falling meteorites, most of which burn up when entering the dense layers of the atmosphere.

The activity of living organisms, which has had a strong influence on the development of oxygen, itself depends to a very large extent on atmospheric conditions. A. delays most of the ultraviolet radiation from the Sun, which has a detrimental effect on many organisms. Atmospheric oxygen is used in the process of respiration by animals and plants, atmospheric carbon dioxide is used in the process of plant nutrition. Climatic factors, especially thermal and moisture regimes, affect health and human activity. Agriculture is especially dependent on climatic conditions. In turn, human activity has an ever-increasing influence on the composition of the atmosphere and the climate regime.

The structure of the atmosphere

Vertical distribution of temperature in the atmosphere and related terminology.

Numerous observations show that A. has a clearly defined layered structure (see figure). The main features of the layered structure of aluminum are determined primarily by the characteristics of the vertical temperature distribution. In the lowest part of the atmosphere—the troposphere, where intense turbulent mixing is observed (see Turbulence in the atmosphere and hydrosphere), the temperature decreases with increasing altitude, and the vertical decrease in temperature averages 6° per 1 km. The height of the troposphere varies from 8-10 km at polar latitudes to 16-18 km at the equator. Due to the fact that air density quickly decreases with height, about 80% of the total mass of air is concentrated in the troposphere. Above the troposphere there is a transition layer - the tropopause with a temperature of 190-220, above which the stratosphere begins. In the lower part of the stratosphere, the decrease in temperature with height stops, and the temperature remains approximately constant up to an altitude of 25 km - the so-called. isothermal region(lower stratosphere); higher the temperature begins to increase - the inversion region (upper stratosphere). Temperatures reach a maximum of ~270 K at the level of the stratopause, located at an altitude of about 55 km. The A layer, located at altitudes from 55 to 80 km, where the temperature again decreases with height, is called the mesosphere. Above it there is a transition layer - mesopause, above which is the thermosphere, where the temperature, increasing with height, reaches very high values (over 1000 K). Even higher (at altitudes of ~ 1000 km or more) is the exosphere, from where atmospheric gases are dispersed into space due to dissipation and where a gradual transition from atmospheric to interplanetary space occurs. Usually, all layers of the atmosphere located above the troposphere are called upper, although sometimes the stratosphere or its lower part is also referred to as the lower layers of the atmosphere.

All structural parameters of Africa (temperature, pressure, density) have significant spatiotemporal variability (latitudinal, annual, seasonal, daily, etc.). Therefore, the data in Fig. reflect only the average state of the atmosphere.

Atmospheric structure diagram:
1 - sea level; 2 - the highest point of the Earth - Mount Chomolungma (Everest), 8848 m; 3 - fair weather cumulus clouds; 4 - powerful cumulus clouds; 5 - shower (thunderstorm) clouds; 6 - nimbostratus clouds; 7 - cirrus clouds; 8 - airplane; 9 - layer of maximum ozone concentration; 10 - mother-of-pearl clouds; 11 - stratospheric balloon; 12 - radiosonde; 1З - meteors; 14 - noctilucent clouds; 15 - auroras; 16 - American X-15 rocket aircraft; 17, 18, 19 - radio waves reflected from ionized layers and returning to Earth; 20 - sound wave reflected from the warm layer and returning to Earth; 21 - the first Soviet artificial Earth satellite; 22 - intercontinental ballistic missile; 23 - geophysical research rockets; 24 - meteorological satellites; 25 - spacecraft Soyuz-4 and Soyuz-5; 26 - space rockets leaving the atmosphere, as well as a radio wave penetrating ionized layers and leaving the atmosphere; 27, 28 - dissipation (slippage) of H and He atoms; 29 - trajectory of solar protons P; 30 - penetration of ultraviolet rays (wavelength l > 2000 and l< 900).

The layered structure of the atmosphere has many other diverse manifestations. The chemical composition of the atmosphere is heterogeneous over altitude. If at altitudes up to 90 km, where there is intense mixing of the atmosphere, the relative composition of the permanent components of the atmosphere remains practically unchanged (this entire thickness of the atmosphere is called the homosphere), then above 90 km - in heterosphere- under the influence of the dissociation of molecules of atmospheric gases by ultraviolet radiation from the sun, a strong change in the chemical composition of the atmosphere occurs with altitude. Typical features of this part of Africa are layers of ozone and the atmosphere's own glow. A complex layered structure is characteristic of atmospheric aerosol—solid particles of terrestrial and cosmic origin suspended in air. The most common aerosol layers are found below the tropopause and at an altitude of about 20 km. The vertical distribution of electrons and ions in the atmosphere is layered, which is expressed in the existence of D-, E-, and F-layers of the ionosphere.

Atmospheric composition

One of the most optically active components is atmospheric aerosol - particles suspended in the air ranging in size from several nm to several tens of microns, formed during the condensation of water vapor and entering the atmosphere from the earth's surface as a result of industrial pollution, volcanic eruptions, and also from space. Aerosol is observed both in the troposphere and in the upper layers of A. The aerosol concentration quickly decreases with height, but this variation is superimposed by numerous secondary maxima associated with the existence of aerosol layers.

Upper atmosphere

Above 20-30 km, as a result of dissociation, the molecules of atoms disintegrate to one degree or another into atoms, and free atoms and new, more complex molecules appear in the atom. Somewhat higher, ionization processes become significant.

The most unstable region is the heterosphere, where the processes of ionization and dissociation give rise to numerous photochemical reactions that determine changes in the composition of air with height. Gravitational separation of gases also occurs here, which is expressed in the gradual enrichment of Africa with lighter gases as the altitude increases. According to rocket measurements, gravitational separation of neutral gases - argon and nitrogen - is observed above 105-110 km. The main components of oxygen in the 100-210 km layer are molecular nitrogen, molecular oxygen and atomic oxygen (the concentration of the latter at the level of 210 km reaches 77 ± 20% of the concentration of molecular nitrogen).

The upper part of the thermosphere consists mainly of atomic oxygen and nitrogen. At an altitude of 500 km, molecular oxygen is practically absent, but molecular nitrogen, the relative concentration of which greatly decreases, still dominates over atomic nitrogen.

In the thermosphere, tidal movements (see Ebb and flow), gravitational waves, photochemical processes, an increase in the mean free path of particles, and other factors play an important role. The results of observations of satellite braking at altitudes of 200-700 km led to the conclusion that there is a relationship between density, temperature and solar activity, which is associated with the existence of daily, semi-annual and annual variations in structural parameters. It is possible that diurnal variations are largely due to atmospheric tides. During periods of solar flares, temperatures at an altitude of 200 km in low latitudes can reach 1700-1900°C.

Above 600 km, helium becomes the predominant component, and even higher, at altitudes of 2-20 thousand km, the Earth’s hydrogen corona extends. At these altitudes, the Earth is surrounded by a shell of charged particles, the temperature of which reaches several tens of thousands of degrees. The Earth's inner and outer radiation belts are located here. The inner belt, filled mainly with protons with energies of hundreds of MeV, is limited to altitudes of 500-1600 km at latitudes from the equator to 35-40°. The outer belt consists of electrons with energies of the order of hundreds of keV. Beyond the outer belt there is an "outermost belt" in which the concentration and flow of electrons is much higher. The intrusion of solar corpuscular radiation (solar wind) into the upper layers of the sun gives rise to auroras. Under the influence of this bombardment of the upper atmosphere by electrons and protons of the solar corona, the atmosphere’s own glow, which was previously called glow of the night sky. When the solar wind interacts with the Earth's magnetic field, a zone is created, called. Earth's magnetosphere, where solar plasma streams do not penetrate.

The upper layers of Africa are characterized by the existence of strong winds, the speed of which reaches 100-200 m/sec. Wind speed and direction within the troposphere, mesosphere and lower thermosphere have great spatiotemporal variability. Although the mass of the upper layers of the sky is insignificant compared to the mass of the lower layers and the energy of atmospheric processes in the high layers is relatively small, apparently there is some influence of the high layers of the sky on the weather and climate in the troposphere.

Radiation, heat and water balances of the atmosphere

Practically the only source of energy for all physical processes developing in Africa is solar radiation. The main feature of the radiation regime of A. is the so-called. greenhouse effect: A. weakly absorbs short-wave solar radiation (most of it reaches the earth's surface), but retains long-wave (entirely infrared) thermal radiation from the earth's surface, which significantly reduces the heat transfer of the Earth into outer space and increases its temperature.

Solar radiation arriving in Africa is partially absorbed in Africa, mainly by water vapor, carbon dioxide, ozone, and aerosols and is scattered on aerosol particles and on fluctuations in the density of Africa. Due to the dispersion of the radiant energy of the Sun in Africa, not only direct solar radiation is observed, but also scattered radiation, together they make up the total radiation. Reaching the earth's surface, the total radiation is partially reflected from it. The amount of reflected radiation is determined by the reflectivity of the underlying surface, the so-called. albedo Due to the absorbed radiation, the earth's surface heats up and becomes a source of its own long-wave radiation directed towards the earth. In turn, the earth also emits long-wave radiation directed towards the earth's surface (the so-called anti-radiation of the earth) and into outer space (the so-called outgoing radiation). Rational heat exchange between the earth's surface and the earth is determined by effective radiation - the difference between the intrinsic radiation of the earth's surface and the counter-radiation absorbed by it. The difference between the short-wave radiation absorbed by the earth's surface and the effective radiation is called radiation balance.

The transformation of the energy of solar radiation after its absorption on the earth's surface and in the atmosphere constitutes the heat balance of the earth. The main source of heat for the atmosphere is the earth's surface, which absorbs the bulk of solar radiation. Since the absorption of solar radiation in the Earth is less than the loss of heat from the Earth into the world space by long-wave radiation, the radiation heat consumption is replenished by the influx of heat to the Earth from the earth’s surface in the form of turbulent heat exchange and the arrival of heat as a result of condensation of water vapor in the Earth. Since the total The amount of condensation throughout Africa is equal to the amount of precipitation, as well as the amount of evaporation from the earth's surface; the arrival of condensation heat in Africa is numerically equal to the heat lost for evaporation on the Earth's surface (see also Water balance).

Some of the energy of solar radiation is spent on maintaining the general circulation of the atmosphere and on other atmospheric processes, but this part is insignificant compared to the main components of the heat balance.

Air movement

Due to the high mobility of atmospheric air, winds are observed at all altitudes. Air movements depend on many factors, the main one being the uneven heating of air in different regions of the globe.

Particularly large temperature contrasts at the Earth's surface exist between the equator and the poles due to differences in the arrival of solar energy at different latitudes. Along with this, the distribution of temperature is influenced by the location of continents and oceans. Due to the high heat capacity and thermal conductivity of ocean waters, the oceans significantly attenuate temperature fluctuations that arise as a result of changes in the arrival of solar radiation throughout the year. In this regard, in temperate and high latitudes, the air temperature over the oceans in summer is noticeably lower than over the continents, and higher in winter.

The uneven heating of the atmosphere contributes to the development of a system of large-scale air currents - the so-called. general atmospheric circulation, which creates horizontal heat transfer in the atmosphere, as a result of which differences in the heating of atmospheric air in individual areas are noticeably smoothed out. Along with this, the general circulation carries out moisture circulation in Africa, during which water vapor is transferred from the oceans to land and the continents are moistened. The movement of air in the general circulation system is closely related to the distribution of atmospheric pressure and also depends on the rotation of the Earth (see Coriolis force). At sea level, the pressure distribution is characterized by a decrease near the equator, an increase in the subtropics (high pressure belts) and a decrease in temperate and high latitudes. At the same time, over the continents of extratropical latitudes, the pressure is usually increased in winter and decreased in summer.

Associated with the planetary pressure distribution is a complex system of air currents, some of which are relatively stable, while others are constantly changing in space and time. Stable air currents include trade winds, which are directed from the subtropical latitudes of both hemispheres to the equator. Monsoons are also relatively stable - air currents that arise between the ocean and the mainland and are seasonal. In temperate latitudes, westerly air currents predominate (from west to east). These currents include large eddies - cyclones and anticyclones, usually extending over hundreds and thousands of km. Cyclones are also observed in tropical latitudes, where they are distinguished by their smaller sizes, but especially high wind speeds, often reaching the strength of a hurricane (so-called tropical cyclones). In the upper troposphere and lower stratosphere there are relatively narrow (hundreds of kilometers wide) jet streams that have sharply defined boundaries, within which the wind reaches enormous speeds - up to 100-150 m/sec. Observations show that the features of atmospheric circulation in the lower part of the stratosphere are determined by processes in the troposphere.

In the upper half of the stratosphere, where temperature increases with altitude, wind speed increases with altitude, with eastern winds dominating in summer and westerly winds in winter. The circulation here is determined by a stratospheric heat source, the existence of which is associated with the intense absorption of ultraviolet solar radiation by ozone.

In the lower part of the mesosphere in temperate latitudes, the speed of the winter westerly transport increases to maximum values - about 80 m/sec, and the summer eastern transport - up to 60 m/sec at a level of about 70 km. Research in recent years has clearly shown that the features of the temperature field in the mesosphere cannot be explained only by the influence of radiation factors. Dynamic factors are of primary importance (in particular, heating or cooling when air descends or rises), and heat sources arising from photochemical reactions (for example, recombination of atomic oxygen) are also possible.

Above the cold mesopause layer (in the thermosphere), the air temperature begins to increase rapidly with altitude. In many respects, this region of Africa is similar to the lower half of the stratosphere. It is likely that the circulation in the lower part of the thermosphere is determined by processes in the mesosphere, and the dynamics of the upper layers of the thermosphere is determined by the absorption of solar radiation here. However, it is difficult to study atmospheric motion at these altitudes due to their significant complexity. Tidal movements (mainly solar semidiurnal and diurnal tides) become of great importance in the thermosphere, under the influence of which wind speeds at altitudes of more than 80 km can reach 100-120 m/sec. A characteristic feature of atmospheric tides is their strong variability depending on latitude, time of year, altitude above sea level and time of day. In the thermosphere, significant changes in wind speed with height are also observed (mainly near the 100 km level), attributed to the influence of gravitational waves. Located in the altitude range of 100-110 km so-called. The turbopause sharply separates the region above from the zone of intense turbulent mixing.

Along with large-scale air currents, numerous local air circulations are observed in the lower layers of the atmosphere (breeze, bora, mountain-valley winds, etc.; see Local winds). In all air currents, wind pulsations are usually observed, corresponding to the movement of air vortices of medium and small sizes. Such pulsations are associated with atmospheric turbulence, which significantly affects many atmospheric processes.

Climate and weather

Differences in the amount of solar radiation arriving at different latitudes of the earth's surface and the complexity of its structure, including the distribution of oceans, continents and major mountain systems, determine the diversity of the Earth's climates (see Climate).

Literature

Meteorology and hydrology for 50 years of Soviet power, ed. E. K. Fedorova, L., 1967;
Khrgian A. Kh., Atmospheric Physics, 2nd ed., M., 1958;
Zverev A.S., Synoptic meteorology and fundamentals of weather prediction, Leningrad, 1968;
Khromov S.P., Meteorology and climatology for geographical faculties, Leningrad, 1964;
Tverskoy P.N., Course of Meteorology, Leningrad, 1962;
Matveev L. T., Fundamentals of general meteorology. Atmospheric Physics, Leningrad, 1965;
Budyko M.I., Thermal balance of the earth's surface, Leningrad, 1956;
Kondratyev K. Ya., Actinometry, Leningrad, 1965;
Khvostikov I. A., High layers of the atmosphere, Leningrad, 1964;
Moroz V.I., Physics of Planets, M., 1967;
Tverskoy P.N., Atmospheric electricity, Leningrad, 1949;
Shishkin N. S., Clouds, precipitation and thunderstorm electricity, M., 1964;
Ozone in the Earth's Atmosphere, ed. G. P. Gushchina, Leningrad, 1966;
Imyanitov I.M., Chubarina E.V., Electricity of the free atmosphere, Leningrad, 1965.

M. I. Budyko, K. Ya. Kondratiev.

This article or section uses text

The atmosphere has a layered structure. The boundaries between layers are not sharp and their height depends on latitude and time of year. The layered structure is the result of temperature changes at different altitudes. Weather is formed in the troposphere (lower about 10 km: about 6 km above the poles and more than 16 km above the equator). And the upper boundary of the troposophere is higher in summer than in winter.

From the surface of the Earth upward these layers are:

Troposphere

Stratosphere

Mesosphere

Thermosphere

Exosphere

Troposphere

The lower part of the atmosphere, up to a height of 10-15 km, in which 4/5 of the total mass of atmospheric air is concentrated, is called the troposphere. It is characteristic that the temperature here drops with height by an average of 0.6°/100 m (in some cases, the vertical temperature distribution varies widely). The troposphere contains almost all of the atmospheric water vapor and produces almost all of the clouds. Turbulence is also highly developed here, especially near the earth's surface, as well as in the so-called jet streams in the upper part of the troposphere.

The height to which the troposphere extends over each location on Earth varies from day to day. In addition, even on average it varies at different latitudes and in different seasons of the year. On average, the annual troposphere extends over the poles to a height of about 9 km, over temperate latitudes up to 10-12 km and above the equator up to 15-17 km. The average annual air temperature at the earth's surface is about +26° at the equator and about -23° at the north pole. At the upper boundary of the troposphere above the equator, the average temperature is about -70°, above the North Pole in winter about -65°, and in summer about -45°.

The air pressure at the upper boundary of the troposphere, corresponding to its height, is 5-8 times less than at the earth's surface. Consequently, the bulk of atmospheric air is located in the troposphere. The processes occurring in the troposphere are directly and decisively important for the weather and climate at the earth's surface.

All water vapor is concentrated in the troposphere and that is why all clouds form within the troposphere. Temperature decreases with altitude.

The sun's rays easily pass through the troposphere, and the heat that radiates from the Earth, heated by the sun's rays, accumulates in the troposphere: gases such as carbon dioxide, methane and water vapor retain heat. This mechanism of warming the atmosphere from the Earth, heated by solar radiation, is called the greenhouse effect. Precisely because the source of heat for the atmosphere is the Earth, the air temperature decreases with height

The boundary between the turbulent troposphere and the calm stratosphere is called the tropopause. This is where fast-moving winds called "jet streams" form.

It was once assumed that the temperature of the atmosphere falls above the troposophere, but measurements in the high layers of the atmosphere have shown that this is not so: immediately above the tropopause the temperature is almost constant, and then begins to increase. Strong horizontal winds blow in the stratosphere without forming turbulence. The air in the stratosphere is very dry and therefore clouds are rare. So-called nacreous clouds are formed.

The stratosphere is very important for life on Earth, as it is in this layer that there is a small amount of ozone, which absorbs strong ultraviolet radiation that is harmful to life. By absorbing ultraviolet radiation, ozone heats the stratosphere.

Stratosphere

Above the troposphere to an altitude of 50-55 km lies the stratosphere, characterized by the fact that the temperature in it, on average, increases with height. The transition layer between the troposphere and stratosphere (1-2 km thick) is called the tropopause.

Above were data on the temperature at the upper boundary of the troposphere. These temperatures are also typical for the lower stratosphere. Thus, the air temperature in the lower stratosphere above the equator is always very low; Moreover, in summer it is much lower than above the pole.

The lower stratosphere is more or less isothermal. But, starting from an altitude of about 25 km, the temperature in the stratosphere quickly increases with altitude, reaching maximum positive values at an altitude of about 50 km (from +10 to +30°). Due to the increase in temperature with altitude, turbulence in the stratosphere is low.

There is negligible water vapor in the stratosphere. However, at altitudes of 20-25 km, very thin, so-called nacreous clouds are sometimes observed in high latitudes. During the day they are not visible, but at night they appear to glow, as they are illuminated by the sun below the horizon. These clouds are made up of supercooled water droplets. The stratosphere is also characterized by the fact that it mainly contains atmospheric ozone, as mentioned above

Mesosphere

Above the stratosphere lies the mesosphere layer, up to approximately 80 km. Here the temperature drops with altitude to several tens of degrees below zero. Due to the rapid drop in temperature with height, turbulence is highly developed in the mesosphere. At altitudes close to the upper boundary of the mesosphere (75-90 km), another special kind of clouds are observed, also illuminated by the sun at night, the so-called noctilucent ones. They are most likely composed of ice crystals.

At the upper boundary of the mesosphere, air pressure is 200 times less than at the earth's surface. Thus, in the troposphere, stratosphere and mesosphere together, up to an altitude of 80 km, lies more than 99.5% of the total mass of the atmosphere. The overlying layers account for a negligible amount of air

At an altitude of about 50 km above the Earth, the temperature begins to fall again, marking the upper limit of the stratosphere and the beginning of the next layer, the mesosphere. The mesosphere has the coldest temperature in the atmosphere: from -2 to -138 degrees Celsius. The highest clouds are also located here: in clear weather they can be seen at sunset. They are called noctilucent (glowing at night).

Thermosphere

The upper part of the atmosphere, above the mesosphere, is characterized by very high temperatures and is therefore called the thermosphere. However, two parts are distinguished in it: the ionosphere, extending from the mesosphere to altitudes of the order of a thousand kilometers, and the outer part lying above it - the exosphere, which turns into the earth's corona.

The air in the ionosphere is extremely rarefied. We have already indicated that at altitudes of 300-750 km its average density is about 10-8-10-10 g/m3. But even with such a low density, each cubic centimeter of air at an altitude of 300 km still contains about one billion (109) molecules or atoms, and at an altitude of 600 km - over 10 million (107). This is several orders of magnitude greater than the content of gases in interplanetary space.

The ionosphere, as the name itself says, is characterized by a very strong degree of ionization of the air - the ion content here is many times greater than in the underlying layers, despite the strong general rarefaction of the air. These ions are mainly charged oxygen atoms, charged nitric oxide molecules, and free electrons. Their content at altitudes of 100-400 km is about 1015-106 per cubic centimeter.

Several layers, or regions, with maximum ionization are distinguished in the ionosphere, especially at altitudes of 100-120 km and 200-400 km. But even in the spaces between these layers, the degree of ionization of the atmosphere remains very high. The position of the ionospheric layers and the concentration of ions in them change all the time. Sporadic collections of electrons with particularly high concentrations are called electron clouds.

The electrical conductivity of the atmosphere depends on the degree of ionization. Therefore, in the ionosphere, the electrical conductivity of air is generally 1012 times greater than that of the earth’s surface. Radio waves experience absorption, refraction and reflection in the ionosphere. Waves with a length of more than 20 m cannot pass through the ionosphere at all: they are reflected by electron layers of low concentration in the lower part of the ionosphere (at altitudes of 70-80 km). Medium and short waves are reflected by the overlying ionospheric layers.

It is due to reflection from the ionosphere that long-distance communication on short waves is possible. Multiple reflections from the ionosphere and the earth's surface allow short waves to travel in a zigzag manner over long distances, bending around the surface of the globe. Since the position and concentration of ionospheric layers are constantly changing, the conditions for absorption, reflection and propagation of radio waves also change. Therefore, for reliable radio communications, continuous study of the state of the ionosphere is necessary. Observations of the propagation of radio waves are precisely the means for such research.

In the ionosphere, auroras and the glow of the night sky, which is close in nature to them in nature, are observed - constant luminescence of atmospheric air, as well as sharp fluctuations in the magnetic field - ionospheric magnetic storms.

Ionization in the ionosphere owes its existence to the action of ultraviolet radiation from the Sun. Its absorption by molecules of atmospheric gases leads to the formation of charged atoms and free electrons, as discussed above. Magnetic field fluctuations in the ionosphere and auroras depend on fluctuations in solar activity. Changes in solar activity are associated with changes in the flow of corpuscular radiation coming from the Sun into the earth's atmosphere. Namely, corpuscular radiation is of primary importance for these ionospheric phenomena.

The temperature in the ionosphere increases with altitude to very high values. At altitudes of about 800 km it reaches 1000°.

When we talk about high temperatures in the ionosphere, we mean that particles of atmospheric gases move there at very high speeds. However, the air density in the ionosphere is so low that a body located in the ionosphere, for example a flying satellite, will not be heated by heat exchange with the air. The temperature regime of the satellite will depend on its direct absorption of solar radiation and on the release of its own radiation into the surrounding space. The thermosphere is located above the mesosphere at an altitude of 90 to 500 km above the Earth's surface. Gas molecules here are highly scattered and absorb X-rays and short-wavelength ultraviolet radiation. Because of this, temperatures can reach 1000 degrees Celsius.

The thermosphere basically corresponds to the ionosphere, where ionized gas reflects radio waves back to Earth, a phenomenon that makes radio communications possible.

Exosphere

Above 800-1000 km, the atmosphere passes into the exosphere and gradually into interplanetary space. The speeds of movement of gas particles, especially light ones, are very high here, and due to the extreme rarefaction of the air at these altitudes, the particles can fly around the Earth in elliptical orbits without colliding with each other. Individual particles can have speeds sufficient to overcome gravity. For uncharged particles, the critical speed will be 11.2 km/sec. Such especially fast particles can, moving along hyperbolic trajectories, fly out of the atmosphere into outer space, “escape”, and dissipate. Therefore, the exosphere is also called the scattering sphere.

Mostly hydrogen atoms, which are the dominant gas in the highest layers of the exosphere, escape.

Recently it was assumed that the exosphere, and with it the Earth’s atmosphere in general, ends at altitudes of about 2000-3000 km. But from observations by rockets and satellites, it appears that hydrogen escaping from the exosphere forms what is called the Earth's corona around the Earth, extending to more than 20,000 km. Of course, the density of gas in the earth's corona is negligible. For every cubic centimeter there are on average only about a thousand particles. But in interplanetary space the concentration of particles (mainly protons and electrons) is at least ten times less.

With the help of satellites and geophysical rockets, the existence in the upper part of the atmosphere and in near-Earth space of the Earth's radiation belt, starting at an altitude of several hundred kilometers and extending tens of thousands of kilometers from the earth's surface, has been established. This belt consists of electrically charged particles - protons and electrons, captured by the Earth's magnetic field and moving at very high speeds. Their energy is on the order of hundreds of thousands of electron volts. The radiation belt constantly loses particles in the earth's atmosphere and is replenished by flows of solar corpuscular radiation.

atmosphere temperature stratosphere troposphere

The exact size of the atmosphere is unknown, since its upper boundary is not clearly visible. However, the structure of the atmosphere has been studied enough for everyone to get an idea of how the gaseous envelope of our planet is structured.

Scientists who study the physics of the atmosphere define it as the region around the Earth that rotates with the planet. FAI gives the following definition:

The boundary between space and the atmosphere runs along the Karman line. This line, according to the definition of the same organization, is an altitude above sea level located at an altitude of 100 km.

Everything above this line is outer space. The atmosphere gradually moves into interplanetary space, which is why there are different ideas about its size.

With the lower boundary of the atmosphere, everything is much simpler - it passes along the surface of the earth's crust and the water surface of the Earth - the hydrosphere. In this case, the border, one might say, merges with the earth and water surfaces, since the particles there are also dissolved air particles.

What layers of the atmosphere are included in the size of the Earth?

Interesting fact: in winter it is lower, in summer it is higher.

It is in this layer that turbulence, anticyclones and cyclones arise, and clouds form. It is this sphere that is responsible for the formation of weather; approximately 80% of all air masses are located in it.

The tropopause is a layer in which the temperature does not decrease with height. Above the tropopause, at an altitude above 11 and up to 50 km is located. The stratosphere contains a layer of ozone, which is known to protect the planet from ultraviolet rays. The air in this layer is thin, which explains the characteristic purple hue of the sky. The speed of air flows here can reach 300 km/h. Between the stratosphere and mesosphere there is a stratopause - a boundary sphere in which the temperature maximum occurs.

The next layer is . It extends to heights of 85-90 kilometers. The color of the sky in the mesosphere is black, so stars can be observed even in the morning and afternoon. The most complex photochemical processes take place there, during which atmospheric glow occurs.

Between the mesosphere and the next layer, there is a mesopause. It is defined as a transition layer in which a temperature minimum is observed. Higher up, at an altitude of 100 kilometers above sea level, is the Karman line. Above this line are the thermosphere (altitude limit 800 km) and the exosphere, which is also called the “dispersion zone”. At an altitude of approximately 2-3 thousand kilometers it passes into the near-space vacuum.

Considering that the upper layer of the atmosphere is not clearly visible, its exact size is impossible to calculate. In addition, in different countries there are organizations that have different opinions on this matter. It should be noted that Karman line can be considered the boundary of the earth’s atmosphere only conditionally, since different sources use different boundary markers. Thus, in some sources you can find information that the upper limit passes at an altitude of 2500-3000 km.

NASA uses the 122 kilometer mark for calculations. Not long ago, experiments were carried out that clarified the border as located at around 118 km.