Definition Atmosphere (from ancient Greek τμός steam and σφα ρα ball) a gas shell surrounding planet Earth, one of the geospheres. Its inner surface covers the hydrosphere and partly the earth's crust, while its outer surface borders 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 the weather on the Earth's surface, meteorology studies weather, and climatology deals with long-term climate variations.

Boundary of the atmosphere The atmosphere is considered to be that region around the Earth in which the gaseous medium rotates together with the Earth as a single whole; With this definition, the atmosphere passes into interplanetary space gradually, in the exosphere, starting at an altitude of about 1000 km from the Earth’s surface; the boundary of the atmosphere can also be conventionally drawn at an altitude of 1300 km. According to the definition proposed by the International Aviation Federation, the boundary of the atmosphere and space is drawn along the Karman line, located at an altitude of about 100 km, where aeronautics becomes completely impossible. NASA uses 122 kilometers as the boundary of the atmosphere; recent experiments clarify the boundary of the Earth's atmosphere and ionosphere as being at an altitude of 118 kilometers.

Physical properties The total mass of air in the atmosphere is (5.15.3) 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 pure dry air is 28.966 g/mol, 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 (~132.4 K); 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 +20 °C and relative humidity 50%. These conditional indicators have purely engineering significance.

The Earth's atmosphere arose as a result of two processes: the evaporation of matter from cosmic bodies as they fell to Earth and the release of gases during volcanic eruptions (degassation of the Earth's mantle). With the separation of the oceans and the emergence of the biosphere, the atmosphere changed due to gas exchange with water, plants, animals and the products of their decomposition in soils and swamps. Currently, 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). The water content in the atmosphere (in the form of water vapor) ranges from 0.2% to 2.5% by volume, and depends mainly on latitude. 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, HF, HBr, HI, Hg vapor, I 2, Br 2, as well as NO and many other gases in small 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).

Structure of the atmosphere Boundary layer of the atmosphere 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 located at an altitude of 810 km in polar, 1012 km in temperate and 1618 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 arise, 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 altitude stops. Stratosphere The layer of the atmosphere located at an altitude of 11 to 50 km. Characterized by a slight change in temperature in the 1125 km layer (lower layer of the stratosphere) and an increase in the 2540 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. Thermopause The region of the atmosphere adjacent to the thermosphere. In this region, the absorption of solar radiation is negligible and the temperature does not actually change with altitude. 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 8090 km. Temperature decreases with height with an average vertical gradient of (0.250.3)°/100 m. The main energy process is radiant heat transfer. Complex photochemical processes involving free radicals, vibrationally excited molecules, etc. cause atmospheric luminescence. Mesopause The transition layer between the mesosphere and thermosphere. There is a minimum in the vertical temperature distribution (about 90 °C).

Exosphere (scattering sphere) The exosphere is the scattering 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 km altitudes 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 km, the exosphere gradually transforms 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. Overview The troposphere accounts for about 80% of the mass of the atmosphere, the stratosphere for 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. Depending on the composition of the gas in the atmosphere, homosphere and heterosphere are distinguished. The heterosphere is a region where gravity affects the separation of gases, since their mixing at such a height 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 experiences 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. The human lungs constantly contain about 3 liters of alveolar air. The partial pressure of oxygen in alveolar air at normal atmospheric pressure is 110 mmHg. 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 at 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 1920 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 a 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 1519 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 radiation (primary cosmic rays) has an intense effect on the body; 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, phenomena familiar to us observed in the lower layers of the atmosphere, such as the propagation of sound, the occurrence of aerodynamic lift and drag, heat transfer by convection, etc., gradually weaken and then completely disappear. air, sound propagation is impossible. Up to altitudes of km, it is still possible to use air resistance and lift for controlled aerodynamic flight. But starting from altitudes of km, the concepts of the M number and the sound barrier, familiar to every pilot, lose their meaning: the conventional Karman line passes there, 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, using air jets and air radiators. At this altitude, as in space generally, the only way to transfer heat is thermal radiation.

History of the formation of the atmosphere According to the most widespread 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 a secondary atmosphere was formed. This atmosphere was restorative. Further, the process of formation of the atmosphere 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 of a tertiary atmosphere, characterized by much less hydrogen and much more 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 ammonia compounds, hydrocarbons, the 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. During the 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 the Earth's biosphere. 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. Organics buried in the ocean, swamps and forests turn into coal, oil and natural gas

Noble gases The source of the noble gases argon, helium and krypton are volcanic eruptions and the 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.

Atmospheric 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 coming 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 air 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 of t n. 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.). Intensive large-scale removal of particulate matter into the atmosphere is one of the possible causes of climate change on the planet.

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Presentation on the topic Atmosphere
The presentation was made by 5th grade student Sidorova Violetta Teacher: Kardanova Yu.R.

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goals and objectives
deepen knowledge about the atmosphere, study the composition of the air, the structure of the atmosphere and the characteristics of the layers, the importance of the atmosphere for the nature of the Earth; the formation of knowledge about the geographical shell - the atmosphere, as a source of existence of life.

Slide 4

Atmosphere - the air envelope of the Earth
The atmosphere is the uppermost shell of the Earth. Its thickness is approximately 2000-3000 km. There is no upper limit to the atmosphere.

Slide 5

Atmospheric composition
The Earth's atmosphere consists of a mixture of gases. This is mainly Nitrogen (N2) - 78%, oxygen (O2) - 21% and the remaining gases - carbon dioxide, water vapor, ozone, helium, hydrogen, argon, etc. - 1%.

Slide 6

The structure of the atmosphere
The thickness of the atmosphere is about 3 thousand km. It contains several layers that differ from each other in temperature and gas composition. The lower layer is the troposphere - the surface of the Earth, but this boundary is relative. Next comes the stratosphere. Even higher are the mesosphere, thermosphere, and exosphere. These are the upper layers of the atmosphere, which pass into outer space at an altitude of 2 - 3 thousand km. above the surface of the Earth.

Slide 7

The troposphere is the lowest layer of the atmosphere, the thickness of which above the poles is 8-10 km, in temperate latitudes - 10-12 km, and above the equator - 16-18 km. The air in the troposphere is heated by the earth's surface, that is, by land and water. Therefore, the air temperature in this layer decreases with height by an average of 0.6 °C for every 100 m. At the upper boundary of the troposphere it reaches -55 °C. At the same time, in the region of the equator at the upper boundary of the troposphere, the air temperature is -70 °C, and in the region of the North Pole -65 °C. About 80% of the mass of the atmosphere is concentrated in the troposphere, almost all the water vapor is located, thunderstorms, storms, clouds and precipitation occur, and vertical (convection) and horizontal (wind) movement of air occurs. We can say that weather is mainly formed in the troposphere.
Troposphere

Slide 8

The stratosphere is a layer of the atmosphere located above the troposphere at an altitude of 8 to 50 km. The color of the sky in this layer appears purple, which is explained by the thinness of the air, due to which the sun's rays are almost not scattered. The stratosphere contains 20% of the mass of the atmosphere. The air in this layer is rarefied, there is practically no water vapor, and therefore almost no clouds and precipitation form. However, stable air currents are observed in the stratosphere, the speed of which reaches 300 km/h. This layer contains ozone (ozone screen, ozonosphere), a layer that absorbs ultraviolet rays, preventing them from reaching the Earth and thereby protecting living organisms on our planet. Thanks to ozone, the air temperature at the upper boundary of the stratosphere ranges from -50 to 4-55 °C. Between the mesosphere and stratosphere there is a transition zone - the stratopause.
Stratosphere

Slide 9

The mesosphere is a layer of the atmosphere located at an altitude of 50-80 km. The air density here is 200 times less than at the Earth's surface. The color of the sky in the mesosphere appears black, and stars are visible during the day. The air temperature drops to -75 (-90)°C. At an altitude of 80 km the thermosphere begins. The air temperature in this layer rises sharply to a height of 250 m, and then becomes constant: at an altitude of 150 km it reaches 220-240 ° C; at an altitude of 500-600 km exceeds 1500 °C.
Mesosphere and thermosphere

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The meaning of atmosphere
All living organisms need air to breathe. Ozone contained in the stratosphere protects living organisms from harmful ultraviolet radiation from the Sun. As a result of human activities, the air becomes dirty. The ozone layer is being destroyed. We need to keep the air clean!

(slide 1 of computer presentation)Today I will tell you about the atmosphere, its structure and what role the atmosphere plays in the life of the Earth.

(slide 2 of computer presentation)“We live at the bottom of the ocean of air,” these words belong to the famous Italian scientist Evangelisto Torricelli.

(slide 3 of computer presentation)The ancient Greeks thought that the air around us was evaporated water, and called the shell surrounding the planet ATMOSPHERE (from the Greek words(atmos - steam) and (sphere - ball).

(slide 4 of the computer presentation).If a globe with a diameter of 35 cm is mentally surrounded by a layer of air 3 cm thick, you will get a model showing the comparative sizes of the Earth and the atmosphere. Our atmosphere is actually more than 1000 km thick.

Is the thickness of the atmosphere the same at different altitudes?

(slide 5-6 of the computer presentation).No, she is different. The atmosphere is conventionally divided into several layers - the troposphere, stratosphere, mesosphere, thermosphere, exosphere.

TO As spacecraft flights have shown, the atmosphere at different altitudes is different. The boundaries of the conditional layers are as follows:

1. troposphere – up to 16 km;
2. stratosphere – up to 50 km;
3. mesosphere – up to 80 km;
4. thermosphere – up to 150 km;
5. exosphere – 150 km and above, passing into outer space.

(slide 7 of the computer presentation). 90% of the total air mass is concentrated in the troposphere. Its thickness is not the same everywhere. Above the equator – 17 km, in the polar regions – 8-9 km, in mid-latitudes – 10-11 km. Why do you think?

IN At equatorial latitudes, the air heats up greatly, expands and increases in volume. In polar latitudes it is the other way around.

(slide 8 of the computer presentation). N The names of the layers of the atmosphere come from Greek and Latin words:

1. troposphere - “tropos” - Greek word - turn. It contains all the water vapor, it is the birthplace of clouds and all natural phenomena;
2. stratosphere – “stratum” is a Latin word – flooring, layer. Here is 1/5 of the atmosphere, this is the kingdom of cold, pearlescent clouds consisting of ice crystals and droplets of supercooled liquid, the sky here is black or dark purple;
3. mesosphere – “meso” - Greek word – middle, intermediate; the air here is thin, contains ozone, noctilucent clouds that are visible only at dusk;
4. thermosphere – “thermo” - the Greek word - heat; There is unprecedented heat here with very low temperatures;
5. exosphere - the outer shell of the atmosphere, extending for 500-600 km, this is the scattering layer

Let us compare the masses and volumes of atmospheric layers by consideringSlide 8 of a computer presentation.

(slide 9 of the computer presentation).

“What aircraft do you know that can rise to different heights?” Airplane, it flies at the boundary of the troposphere and stratosphere; stratospheric balloon in the stratosphere; radiosonde flies in the stratosphere;spaceship in the thermosphere; the first Soviet artificial satellite of the Earthat the boundary of the thermosphere and exosphere;weather satellite in the exosphere.

Look at the last vertical axis in the figure and answer the question:

How does the density of the atmosphere change with altitude? The density of the atmosphere decreases with height. Measurements show that air density decreases rapidly with altitude. Thus, at an altitude of 5.5 km above sea level, the air density is 2 times less than at the Earth’s surface. At an altitude of 11 km it is 4 times less and so on... the higher you go, the thinner the air. And finally, in the highest layers - hundreds and thousands of kilometers above the Earth - the atmosphere gradually turns into airless space. Thus, the atmosphere does not have a clear boundary.

What is air? What we breathe? Element? Wind? Something homogeneous? Complex connection?(slide 10 of the computer presentation).

Until the middle of the 18th century, scientists did not know that air is a mixture of gases. Scientists from many countries and different eras have dealt with this problem:

Robert Boyle (England), M.V. Lomonosov (Russia), Karl Scheele (Sweden), Joseph Priestley (England), Antoine Lavoisier (France), Henry Cavendish (England), William Ramsay (England).

(slide 11 of the computer presentation). According to modern concepts, air contains gases. Consider a pie chart. We see that nitrogen – 78%, oxygen – 21%, inert gases – 0.94%, carbon dioxide – 0.03%

There are variable constituents in the air, accounting for 0.03%. What are these variable components?

These are nitrogen oxides, sulfur oxides, carbon monoxide, ammonia, elemental sulfur, hydrogen sulfide, water and dust. These substances enter the atmosphere naturally. Water in the air determines its humidity and contributes to the formation of clouds and precipitation. Other substances play a negative role. They are air pollutants.

(slide 12 of the computer presentation)– when a volcano erupts, sulfur dioxide, hydrogen sulfide, and elemental sulfur enter the atmosphere.

– Dust storms contribute to the appearance of dust.

– the entry of nitrogen oxides into the atmosphere is facilitated by lightning discharges, during which nitrogen and oxygen in the air react with each other, as well as forest fires and the burning of peat bogs.

The processes of destruction of organic substances are accompanied by the formation of various gaseous sulfur compounds.

The ozone layer is important(slide 13 of the computer presentation)located in the statosphere. Ozone is formed in the upper rarefied layers under the influence of ultraviolet rays.

(animation - slide 14 of a computer presentation).

Why does the Earth have an atmosphere? What forces act on air?(slide 15 of the computer presentation).

Air volume 1m 3 has a mass of 1.3 kg.(slide 16 of the computer presentation).From the side of the Earth, the force of gravity acts on the air, like any other body. He is attracted by the Earth. But the molecules of gases that make up the atmosphere do not fall to the surface of the Earth. They are in continuous chaotic movement.

P Why then do the molecules not leave the Earth? To leave the Earth, a molecule, like a rocket, needs to have a speed of 11.2 km/s (second escape velocity)(slide 17 of the computer presentation), but the speed of gas molecules is much less than this value. So, two factors - random movement and the action of gravity, lead to the fact that molecules are located around the Earth, forming an atmosphere.

In the Solar System, the planets have an atmosphere, but it is different.

(slide 18 of the computer presentation)– on Venus and Mars – carbon dioxide, on the giant planets – helium, methane, ammonia(slide 19 of the computer presentation), there is no atmosphere on the Moon and Mercury(slide 20 of the computer presentation).

In 1862, the English naturalist James Glaisher and a friend went on a hot air balloon trip wearing only their jackets.(slide 21 of the computer presentation). Having risen to a height of 11 km, the travelers lost consciousness and were severely frostbitten. They did not know that for every 1500 m rise the temperature drops by 8○ S.

Why is this happening?

(slide 22 of the computer presentation).Difficulties encountered by travelers:

1. Clouds are a thick cold fog in which nothing is visible;

2. Lack of oxygen, because with a change in altitude, the air becomes rarefied;

3. Cold - for every kilometer of altitude, the temperature drops by 6°C;

(slide 23 of the computer presentation). N At high altitudes, the air is thinner and molecules rarely collide, so their speed decreases and the air temperature drops.But this is the picture in the troposphere at an altitude of 17 km. At this altitude above the tropics the temperature is 75 0 C, in the stratosphere the temperature rises to 0 0 C, in the mesosphere drops to – 85 0 C, in the thermosphere at an altitude of 400 km the temperature is 727 0 -927 0 C, in the exosphere the temperature is 1000 0 – 1200 0 C.

(slide 24 of the computer presentation).

How do spaceships fly at such altitudes? A The atmosphere is very rarefied, almost reaching a vacuum. Such an atmosphere does not provide resistance to ships, which allows them to remain in orbit for years.

(slide 25 of the computer presentation).

Take care of your planet!

There is one garden planet

In this cold space.

Only here the forests are noisy,

Calling migratory birds.

And dragonflies are only here

They look into the river in surprise.

Here he lives carelessly in the grass

The chirping songbird grasshopper,

Young wind, hooligan,

The old ocean tickles

Graceful dolphins

Waltz dancing and singing

In general, they live happily.

It's only a golden morning here,

The air is soft blue,

Breathe easily and to your heart's content.

We sometimes forget:

The air is leased to us,

He is one for all earthlings.

For life to triumph,

We need to protect the air.

Take care of your planet

After all, there is no other one in the world!

Galina Marshanova.

(slide 26 of the computer presentation).

Atmosphere meaning:

1. Protects the earth from overheating and hypothermia.
2. Protects against meteorites.
3. Protects against ultraviolet radiation.
4. Necessary for breathing.
5. Aesthetic value

(animation - slide 27 of a computer presentation).

(animation - slide 28 of a computer presentation).

The role of the atmosphere in the life of the Earth

(slide 29 of the computer presentation).

(slide 30 of the computer presentation).

1. Air is essential for all life on Earth.
2. The atmosphere - the armor of the Earth - protects against the bombardment of meteorites
3. The ozone layer blocks harmful cosmic radiation
4. Atmosphere is a world of sounds
5. Without the atmosphere, the Earth would be lifeless like the Moon, there would be no rivers, lakes, seas
6. The atmosphere is the Earth's clothing; it will not allow heat to escape into space

Slide 2

The atmosphere (from the Greek atmos - steam and spharia - ball) is the air shell of the Earth, rotating with it. The development of the atmosphere was closely related to the geological and geochemical processes occurring on our planet, as well as to the activities of living organisms.

The lower boundary of the atmosphere coincides with the surface of the Earth, since air penetrates into the smallest pores in the soil and is dissolved even in water.

The upper boundary at an altitude of 2000-3000 km gradually passes into outer space.

Thanks to the atmosphere, which contains oxygen, life on Earth is possible. Atmospheric oxygen is used in the breathing process of humans, animals, and plants.

Slide 3

LAYERS OF THE ATMOSPHERE

The atmosphere has a layered structure.

From the surface of the Earth upward these layers are:

• Troposphere
• Stratosphere
• Mesosphere
• Thermosphere
• Exosphere

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The troposphere is the lowest layer of the atmosphere, the thickness of which above the poles is 8-10 km, in temperate latitudes - 10-12 km, and above the equator - 16-18 km.

The air in the troposphere is heated by the earth's surface, that is, by land and water. Therefore, the air temperature in this layer decreases with height by an average of 0.6 °C for every 100 m. At the upper boundary of the troposphere it reaches -55 °C. At the same time, in the region of the equator at the upper boundary of the troposphere, the air temperature is -70 °C, and in the region of the North Pole -65 °C.

About 80% of the mass of the atmosphere is concentrated in the troposphere, almost all the water vapor is located, thunderstorms, storms, clouds and precipitation occur, and vertical (convection) and horizontal (wind) movement of air occurs.

We can say that weather is mainly formed in the troposphere.

Troposphere

Slide 6

The stratosphere is a layer of the atmosphere located above the troposphere at an altitude of 8 to 50 km. The color of the sky in this layer appears purple, which is explained by the thinness of the air, due to which the sun's rays are almost not scattered.

The stratosphere contains 20% of the mass of the atmosphere. The air in this layer is rarefied, there is practically no water vapor, and therefore almost no clouds and precipitation form. However, stable air currents are observed in the stratosphere, the speed of which reaches 300 km/h.

This layer contains ozone (ozone screen, ozonosphere), a layer that absorbs ultraviolet rays, preventing them from reaching the Earth and thereby protecting living organisms on our planet. Thanks to ozone, the air temperature at the upper boundary of the stratosphere ranges from -50 to 4-55 °C.

Between the mesosphere and stratosphere there is a transition zone - the stratopause.

Stratosphere

Slide 7

The mesosphere is a layer of the atmosphere located at an altitude of 50-80 km. The air density here is 200 times less than at the Earth's surface. The color of the sky in the mesosphere appears black, and stars are visible during the day. The air temperature drops to -75 (-90)°C.

At an altitude of 80 km the thermosphere begins. The air temperature in this layer rises sharply to a height of 250 m, and then becomes constant: at an altitude of 150 km it reaches 220-240 ° C; at an altitude of 500-600 km exceeds 1500 °C.

Mesosphere and thermosphere

Slide 8

In the mesosphere and thermosphere, under the influence of cosmic rays, gas molecules disintegrate into charged (ionized) particles of atoms, so this part of the atmosphere is called the ionosphere - a layer of very rarefied air, located at an altitude of 50 to 1000 km, consisting mainly of ionized oxygen atoms, molecules nitric oxide and free electrons

The atmosphere is the air envelope of the Earth, and in order to teach a geography lesson on this topic, there is a good presentation on 6th grade geography, which the World of Geography offered you to download, as usual, for free. During the lesson, 6th grade students learn a lot of interesting things about the atmosphere, about which they seem to be well aware. But in fact, the situation is such that they know about the composition of the air they breathe, but most likely they have not yet heard anything about the stratosphere. Therefore, there is a reason to download the presentation and, based on its slides, show and tell interesting information about the atmosphere.

View presentation content
"sostavatm"

What does the atmosphere consist of? and how it works

Do you have a blanket, children?

So that the whole Earth is covered

So that there is enough for everyone,

And besides, it wasn’t visible?

Neither fold nor unfold,

Neither touch nor look?

It would let in rain and light,

Yes, but it seems not?!

Atmosphere - this is the air shell of the Earth

Atmospheric composition

OXYGEN. Oxygen reserves in the atmosphere are replenished by plants.

CARBON DIOXIDE. Carbon dioxide accumulates in the atmosphere as a result of volcanic eruptions, the respiration of living organisms and the combustion of fuels.

WATER VAPOR. Water vapor enters the air due to the evaporation of water.

Carbon dioxide, together with water vapor, “save” the heat of our planet: the atmosphere transmits more energy from the Sun to the earth’s surface than the Earth releases into the surrounding outer space.

OZONE. Ozone is formed from oxygen under the influence of sunlight and electrical discharges. It has a fresh smell, like what we smell after a thunderstorm. There is very little of this gas in the atmosphere, but at an altitude of 20-30 km there is a layer of air with a higher ozone content. It is called the ozone screen. It, like a shield, protects all living things from the destructive radiation of the Sun.

IMPURITIES. In addition to gases, there are also solid impurities in the atmospheric air. These small particles are formed as a result of the destruction of rocks, volcanic eruptions, dust storms, and fuel combustion. On the one hand, they pollute the air, but, on the other hand, without them clouds cannot form.

Troposphere is the lower layer of the atmosphere, extending to a height of 8-10 km above the poles, 10-12 km in mid-latitudes and 16-18 km above the equator.

There are more than 4 / 5 of all atmospheric air. Moreover, more than half of it is concentrated up to a height of 5 km. The air temperature here decreases with height and reaches -55 C at the upper limit. The troposphere contains almost all atmospheric moisture. Clouds form in it, bringing rain, snow, and hail. Here there is a constant movement of air, and wind is formed. Human and plant life takes place in the troposphere.

Stratosphere is a layer of the atmosphere lying above the troposphere up to an altitude of 55 km.

The air in the stratosphere is thinner than in the troposphere. Almost no clouds form in it, since there is very little water vapor. The air temperature here increases with height and at the upper limit is close to 0 °C.

Above the stratosphere, several more atmospheric layers are distinguished, which gradually turn into airless space.

Run the test

1. The atmosphere is a shell

A. Gas

b. Water

V. Salty

2. The lowest layer of the atmosphere:

A. Stratosphere

b. Troposphere

V. Upper atmosphere

Run the test

3. Oxygen in the air contains:

4. In the troposphere are formed:

A. Clouds

b. Ultra-violet rays

V. Groundwater