Temperature of the layers of the earth's atmosphere. Layers of the atmosphere. The concept of the earth's atmosphere

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

Tropopause

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

Stratosphere

The layer of the atmosphere located at an altitude of 11 to 50 km. A slight change in temperature in the layer of 11-25 km (the lower layer of the stratosphere) and its increase in the layer 25-40 km from -56.5 to 0.8 ° (the upper layer of the stratosphere or the inversion region) are characteristic. 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 the mesosphere.

Stratopause

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

Mesosphere

Atmosphere of earth

Boundary of the earth's atmosphere

Thermosphere

The upper limit is about 800 km. The temperature rises to altitudes of 200-300 km, where it reaches values ​​of the order of 1500 K, after which it remains almost constant up to high altitudes. Under the influence of ultraviolet and X-ray solar radiation and cosmic radiation, air ionization ("polar lights") occurs - the main areas of the ionosphere lie inside the thermosphere. At altitudes over 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 to the top of the thermosphere. In this area, the absorption of solar radiation is negligible and the temperature does not actually change with altitude.

Exosphere (Orb of Dispersion)

Up to an altitude of 100 km, the atmosphere is a homogeneous, well-mixed mixture of gases. In higher layers, the distribution of gases along the height depends on their molecular masses, the concentration of heavier gases decreases faster with distance from the Earth's surface. Due to the decrease in the density of gases, 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 the temperature and density of gases are observed in time and space.

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 is only a fraction of the interplanetary matter. Another part is made up of dust-like particles of cometary and meteoric origin. In addition to extremely rarefied dust-like particles, electromagnetic and corpuscular radiation of solar and galactic origin penetrates into this space.

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

Depending on the composition of the gas in the atmosphere, homosphere and heterosphere. Heterosphere- this is the area where gravity affects the separation of gases, since their mixing at this height is negligible. Hence the variable composition of the heterosphere. Below it lies a well-mixed part of the atmosphere, homogeneous in composition, called the homosphere. The boundary between these layers is called the turbopause; it lies at an altitude of about 120 km.

Physiological and other properties of the atmosphere

Already at an altitude of 5 km above sea level, an untrained person develops oxygen starvation and without adaptation, the person's working capacity is significantly reduced. This is where the physiological zone of the atmosphere ends. Human breathing becomes impossible at an altitude of 9 km, although the atmosphere contains oxygen up to about 115 km.

The atmosphere supplies us with the oxygen we need to breathe. However, due to the drop in the total pressure of the atmosphere as it rises to altitude, the partial pressure of oxygen also decreases accordingly.

In rarefied layers of air, the propagation of sound is impossible. Up to heights of 60-90 km, it is still possible to use the resistance and lift of the air for controlled aerodynamic flight. But starting from heights of 100-130 km, the concepts of the number M and the sound barrier, familiar to every pilot, lose their meaning: the conditional Karman line passes there, beyond which the area of ​​purely ballistic flight begins, which can be controlled only using reactive forces.

At altitudes above 100 km, the atmosphere also lacks another remarkable property - the ability to absorb, conduct and transfer thermal energy by convection (i.e., by mixing air). This means that various elements of equipment, equipment of the orbiting space station will not be able to cool from the outside as it is usually done on an airplane - with the help of air jets and air radiators. At this altitude, as in space in general, the only way to transfer heat is thermal radiation.

The history of the formation of the atmosphere

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

• leakage of light gases (hydrogen and helium) into interplanetary space;
• chemical reactions 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 hydrogen content and a much higher nitrogen and carbon dioxide content (formed as a result of chemical reactions from ammonia and hydrocarbons).

Nitrogen

The formation of a large amount of nitrogen N 2 is due to the oxidation of the ammonia-hydrogen atmosphere with molecular oxygen O 2, which began to flow from the planet's surface as a result of photosynthesis, starting from 3 billion years ago. Also, nitrogen N 2 is 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 strike). Oxidation of molecular nitrogen by ozone with electrical discharges in small quantities is used in the industrial production of nitrogen fertilizers. It can be oxidized with low energy consumption and converted into a biologically active form by cyanobacteria (blue-green algae) and nodule bacteria that form rhizobial symbiosis with legumes, the so-called. siderates.

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, the ferrous form of iron contained in the oceans, etc. At the end of this stage, the oxygen content in the atmosphere began to grow. Gradually, a modern atmosphere with oxidizing properties was formed. Since this caused serious and abrupt changes in many processes taking place in the atmosphere, lithosphere and biosphere, this event was called the Oxygen Catastrophe.

Noble gases

Air pollution

V recent times man began to influence the evolution of the atmosphere. The result of his activities was a constant significant increase in the content of carbon dioxide in the atmosphere due to the combustion of hydrocarbon fuels accumulated in previous geological eras. Enormous 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 matter of plant and animal origin, as well as due to volcanism and human production activities. 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 СО 2 in the atmosphere will double and may lead to global climate changes.

Fuel combustion is the main source of polluting gases (CO, SO 2). Sulfur dioxide is oxidized by atmospheric oxygen to SO 3 in the upper atmosphere, which in turn interacts with water and ammonia vapors, and the resulting sulfuric acid (H 2 SO 4) and ammonium sulfate ((NH 4) 2 SO 4) return to the surface of the Earth in the form of the so-called. acid rain. The use of internal combustion engines leads to significant pollution of the atmosphere 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 eruption, dust storms, drift sea ​​water and pollen of plants, etc.), and economic activities human (mining of ores and building materials, fuel combustion, cement making, etc.). Intense large-scale removal of solid particles into the atmosphere is one of the possible causes of climate change on the planet.

see also

• Jacchia (atmosphere model)

Notes (edit)

Links

Literature

1. V. V. Parin, F. P. Kosmolinsky, B. A. Dushkov"Space biology and medicine" (2nd edition, revised and enlarged), M .: "Education", 1975, 223 pages.
2. N.V. Gusakova"Chemistry of the Environment", Rostov-on-Don: Phoenix, 2004, 192 with ISBN 5-222-05386-5
3. Sokolov V.A. Geochemistry of natural gases, M., 1971;
4. McEwen M., Phillips L. Chemistry of the atmosphere, M., 1978;
5. Work K., Warner S. Air pollution. Sources and Control, trans. from English., M .. 1980;
6. Monitoring of background pollution of natural environments. v. 1, L., 1982.

The atmosphere is one of the most important components of our planet. It is she who "shelters" people from the harsh conditions of outer space, such as solar radiation and space debris. At the same time, many facts about the atmosphere are unknown to most people.

True color of the sky

While it's hard to believe, the sky is actually purple. When light enters the atmosphere, air and water particles absorb the light, scattering it. At the same time, the violet color is scattered most of all, which is why people see the blue sky.

Exclusive element in the Earth's atmosphere

As many remember from school, the Earth's atmosphere consists of approximately 78% nitrogen, 21% oxygen and small impurities of argon, carbon dioxide and other gases. But few people know that our atmosphere is the only one on this moment discovered by scientists (in addition to comet 67P), which has free oxygen. Because oxygen is a highly reactive gas, it often reacts with other chemicals in space. Its pure form on Earth makes the planet habitable.

White stripe in the sky

Surely, some sometimes wondered why there is a white stripe in the sky behind a jet plane. These white traces, known as contrails, are formed when hot and humid exhaust gases from an aircraft engine mix with colder outside air. The water vapor from the exhaust gas freezes and becomes visible.

The main layers of the atmosphere

The Earth's atmosphere consists of five main layers, which make possible life on the planet. The first of these, the troposphere, extends from sea level to an altitude of about 17 km to the equator. Most of the weather events take place in it.

Ozone layer

The next layer of the atmosphere, the stratosphere, reaches an altitude of about 50 km at the equator. It contains an ozone layer that protects people from dangerous ultraviolet rays. Even though this layer is above the troposphere, it may actually be warmer due to the energy it absorbs. sun rays... Most jets and weather balloons fly in the stratosphere. Airplanes can fly faster in it because they are less affected by gravity and friction. Weather balloons, on the other hand, can get a better idea of ​​storms, most of which occur lower in the troposphere.

Mesosphere

The mesosphere is the middle layer extending up to 85 km above the planet's surface. The temperature in it fluctuates around -120 ° C. Most of the meteors that enter the Earth's atmosphere burn up in the mesosphere. The last two layers passing into space are the thermosphere and exosphere.

Disappearance of the atmosphere

The earth has most likely lost its atmosphere several times. When the planet was covered in oceans of magma, massive interstellar objects crashed into it. These influences, which also formed the moon, may have formed the planet's atmosphere for the first time.

If there were no atmospheric gases ...

Without various gases in the atmosphere, the Earth would be too cold for human existence. Water vapor, carbon dioxide and other atmospheric gases absorb heat from the sun and "distribute" it across the planet's surface, helping to create a climate suitable for habitation.

Ozone formation

The notorious (and essential) ozone layer was created when oxygen atoms reacted with the sun's ultraviolet light to form ozone. It is ozone that absorbs most of the harmful radiation from the sun. Despite its importance, the ozone layer was formed relatively recently after enough life arose in the oceans to release the amount of oxygen necessary to create a minimum concentration of ozone into the atmosphere.

Ionosphere

The ionosphere is so named because high-energy particles from space and from the Sun help form ions, creating an "electrical layer" around the planet. When satellites did not exist, this layer helped to reflect radio waves.

Acid rain

Acid rain, which destroys entire forests and devastates aquatic ecosystems, is formed in the atmosphere when sulfur dioxide or nitric oxide particles mix with water vapor and fall to the ground as rain. These chemical compounds are also found in nature: sulfur dioxide is produced during volcanic eruptions, and nitric oxide - during lightning strikes.

Lightning power

Lightning is so powerful that a single discharge can heat the surrounding air up to 30,000 ° C. Rapid heating causes an explosive expansion of nearby air, which is heard in the form of a sound wave called thunder.

Polar Lights

Aurora Borealis and Aurora Australis (northern and southern auroras) are caused by ionic reactions occurring in the fourth level of the atmosphere, the thermosphere. When highly charged particles from the solar wind collide with air molecules above the planet's magnetic poles, they glow and create magnificent light shows.

Sunsets

Sunsets often look like burning skies, as small atmospheric particles scatter light, reflecting it in shades of orange and yellow. The same principle underlies the formation of rainbows.

Inhabitants of the upper atmosphere

In 2013, scientists discovered that tiny microbes can survive miles above the Earth's surface. At an altitude of 8-15 km above the planet, microbes were discovered that destroy organic chemicals that float in the atmosphere, "feeding" on them.

The atmosphere has distinct layers of air. Air layers differ in temperature, gas difference and their density and pressure. It should be noted that the stratosphere and troposphere layers protect the Earth from solar radiation. In the higher layers, a living organism can receive lethal dose ultraviolet solar spectrum. To quickly go to the desired atmosphere layer, click on the appropriate layer:

Troposphere and tropopause

Troposphere - temperature, pressure, altitude

The upper border is kept at around 8-10 km. In temperate latitudes 16 - 18 km, and in polar latitudes 10 - 12 km. Troposphere- this is the lower main layer of the atmosphere. This layer contains more than 80% of the total mass of atmospheric air and nearly 90% of all water vapor. It is in the troposphere that convection and turbulence arise, clouds form, and cyclones occur. Temperature decreases with increasing height. Gradient: 0.65 ° / 100 m. Heated earth and water heat the supplied air. The heated air rises to the top, cools and forms clouds. The temperature in the upper boundaries of the layer can reach - 50/70 ° C.

It is in this layer that climatic changes occur. weather conditions... The lower boundary of the troposphere is called ground as it has many volatile microorganisms and dust. The wind speed increases with increasing height in this layer.

Tropopause

It is a transitional layer of the troposphere to the stratosphere. Here the dependence of the temperature decrease with increasing altitude stops. The tropopause is the minimum altitude where the vertical temperature gradient drops to 0.2 ° C / 100 m. The tropopause height depends on strong climatic events such as cyclones. Above cyclones, the tropopause height decreases, and above anticyclones it increases.

Stratosphere and Stratopause

The height of the stratospheric layer is approximately 11 to 50 km. There is a slight change in temperature at an altitude of 11 - 25 km. At an altitude of 25-40 km, there is inversion temperature, from 56.5 rises to 0.8 ° C. From 40 km to 55 km, the temperature is kept at around 0 ° C. This area is called - Stratopause.

In the Stratosphere, the effect of solar radiation on gas molecules is observed, they dissociate into atoms. There is almost no water vapor in this layer. Modern supersonic commercial aircraft fly at altitudes up to 20 km due to stable flight conditions. High-altitude meteorological balloons rise to an altitude of 40 km. Stable air currents are present here, their speed reaches 300 km / h. Also in this layer is concentrated ozone, a layer that absorbs ultraviolet rays.

Mesosphere and Mesopause - composition, reactions, temperature

The mesosphere layer starts at about 50 km and ends at 80 - 90 km. Temperatures decrease with an increase in altitude of about 0.25-0.3 ° C / 100 m. The main energetic effect here is radiant heat transfer. Complex photochemical processes with the participation of free radicals (has 1 or 2 unpaired electron) because they implement glow atmosphere.

Almost all meteors burn out in the mesosphere. Scientists have named this zone - Ignorosphere... This area is difficult to explore, as aerodynamic aviation is very poor here due to the density of the air, which is 1000 times less than on Earth. And for the launch of artificial satellites, the density is still very high. Research is carried out using meteorological rockets, but this is perversity. Mesopause transition layer between the mesosphere and thermosphere. Has a temperature of at least -90 ° C.

Pocket Line

Pocket line called the border between the Earth's atmosphere and space. According to the International Aeronautical Federation (FAI), the height of this border is 100 km. This definition was given in honor of the American scientist Theodore Von Karman. He determined that at about this altitude, the density of the atmosphere is so low that aerodynamic aviation becomes impossible here, since the speed of the flying device must be greater first space speed... At such a height, the concept of a sound barrier loses its meaning. Here it is possible to control the aircraft only due to the reactive forces.

Thermosphere and Thermopause

The upper boundary of this layer is about 800 km. The temperature rises to about an altitude of 300 km, where it reaches about 1500 K. Above, the temperature remains unchanged. In this layer there is Polar Lights- occurs as a result of exposure to solar radiation on the air. This process is also called atmospheric oxygen ionization.

Due to the low air density, flights above the Karman line are feasible only along ballistic trajectories. All manned orbital flights (except for flights to the Moon) take place in this layer of the atmosphere.

Exosphere - density, temperature, altitude

The exosphere is over 700 km high. Here the gas is very rarefied, and the process takes place dissipation- particle leakage into interplanetary space. The speed of such particles can reach 11.2 km / sec. The growth of solar activity leads to the expansion of the thickness of this layer.

• The gas shell does not fly into space due to gravity. Air is made up of particles that have their own mass. From the law of gravitation, one can deduce that every object with mass is attracted to the Earth.
• Buys-Balllot's law says that if you are in the Northern Hemisphere and stand with your back to the wind, then there will be a high pressure zone on the right, and low pressure on the left. In the Southern Hemisphere, the opposite will be true.

The shell of gas that surrounds our planet Earth, known as the atmosphere, is made up of five main layers. These layers originate on the surface of the planet, from sea level (sometimes below) and rise to outer space in the following sequence:

• Troposphere;
• Stratosphere;
• Mesosphere;
• Thermosphere;
• Exosphere.

Diagram of the main layers of the Earth's atmosphere

In between each of these five main layers are transition zones called "pauses" where changes in temperature, composition and air density occur. Together with the pauses, the Earth's atmosphere includes a total of 9 layers.

Troposphere: where the weather happens

Of all the layers of the atmosphere, the troposphere is the one with which we are most familiar (whether you realize it or not), since we live at its bottom - the surface of the planet. It envelops the surface of the Earth and extends upwards for several kilometers. The word troposphere means "changing the globe." A very apt name, since this layer is where our daily weather takes place.

Starting from the surface of the planet, the troposphere rises to a height of 6 to 20 km. The lower third of the layer, closest to us, contains 50% of all atmospheric gases. It is the only part of the entire composition of the atmosphere that breathes. Due to the fact that the air is heated from below by the earth's surface, which absorbs the thermal energy of the Sun, the temperature and pressure of the troposphere decrease with increasing altitude.

At the top is a thin layer called the tropopause, which is just a buffer between the troposphere and stratosphere.

Stratosphere: home of the ozone

The stratosphere is the next layer of the atmosphere. It stretches from 6-20 km to 50 km above the earth's surface. This is the layer in which most commercial airliners fly and hot air balloons travel.

Here, the air does not flow up and down, but moves parallel to the surface in very fast air currents. Temperatures rise as you climb, thanks to the abundance of natural ozone (O 3), a byproduct of solar radiation and oxygen that has the ability to absorb the sun's harmful ultraviolet rays (any rise in temperature with altitude in meteorology is known as "inversion") ...

Because the stratosphere has warmer temperatures at the bottom and cooler at the top, convection (vertical movement of air masses) is rare in this part of the atmosphere. In fact, you can view a storm raging in the troposphere from the stratosphere as the layer acts as a convection “cap” through which storm clouds cannot penetrate.

After the stratosphere, there is again a buffer layer, this time called the stratopause.

Mesosphere: middle atmosphere

The mesosphere is located approximately 50-80 km from the Earth's surface. The upper mesosphere is the coldest natural place on Earth, where temperatures can drop below -143 ° C.

Thermosphere: upper atmosphere

The mesosphere and mesopause are followed by the thermosphere, located between 80 and 700 km above the planet's surface, and contains less than 0.01% of all air in the atmospheric envelope. Temperatures here reach up to + 2000 ° C, but due to the strong rarefaction of the air and the lack of gas molecules for heat transfer, these high temperatures are perceived as very cold.

Exosphere: the border of the atmosphere and space

At an altitude of about 700-10,000 km above the earth's surface, there is an exosphere - the outer edge of the atmosphere, bordering on space. Here meteorological satellites revolve around the Earth.

How about the ionosphere?

The ionosphere is not a separate layer, but in fact the term is used to refer to the atmosphere at an altitude of 60 to 1000 km. It includes the uppermost parts of the mesosphere, the entire thermosphere and part of the exosphere. The ionosphere gets its name because in this part of the atmosphere, the radiation from the Sun is ionized when it passes the Earth's magnetic fields on and. This phenomenon is observed from the ground like the northern lights.

Space is filled with energy. Energy fills space unevenly. There are places of her concentration and discharge. This is how the density can be estimated. The planet is an ordered system, with the maximum density of matter in the center and with a gradual decrease in concentration towards the periphery. The forces of interaction determine the state of matter, the form in which it exists. Physics describes the state of aggregation of substances: solid, liquid, gas and so on.

The atmosphere is the gaseous environment that surrounds the planet. The atmosphere of the Earth allows free movement and allows light to pass through, creating a space in which life thrives.

The area from the surface of the earth to an altitude of approximately 16 kilometers (from the equator to the poles, the lower value, also depends on the season) is called the troposphere. The troposphere is a layer in which about 80% of all atmospheric air and almost all water vapor are concentrated. It is here that the processes that shape the weather take place. Pressure and temperature drop with altitude. The reason for the decrease in air temperature is an adiabatic process, when the gas expands, it cools. At the upper border of the troposphere, values ​​can reach -50, -60 degrees Celsius.

Then the Stratosphere begins. It extends upwards for 50 kilometers. In this layer of the atmosphere, the temperature increases with height, gaining a value at the upper point of about 0 C. The increase in temperature is caused by the absorption of ultraviolet rays by the ozone layer. Radiation causes a chemical reaction. Oxygen molecules break down into single atoms, which can combine with normal oxygen molecules, resulting in ozone.

Radiation from the sun with wavelengths between 10 and 400 nanometers is classified as ultraviolet. The shorter the wavelength of UV radiation, the greater the danger it poses to living organisms. Only a small fraction of radiation reaches the surface of the Earth, moreover, the less active part of its spectrum. This feature of nature allows a person to get a healthy sunburn.

The next layer of the atmosphere is called the Mesosphere. The limits are approximately 50 km to 85 km. In the mesosphere, the concentration of ozone, which could trap UV energy, is low, so the temperature again begins to fall with height. At the peak point, the temperature drops to -90 C, some sources indicate a value of -130 C. In this layer of the atmosphere, most of the meteoric bodies burn out.

The layer of the atmosphere, stretching from a height of 85 km to a distance of 600 km from the Earth, is called the Thermosphere. The thermosphere is the first to meet solar radiation, including the so-called vacuum ultraviolet.

Vacuum UV is trapped by the air environment, thereby heating this layer of the atmosphere to enormous temperatures. However, since the pressure here is extremely small, this seemingly incandescent gas does not have the same effect on objects as under conditions on the surface of the earth. On the contrary, objects placed in such an environment will cool down.

At an altitude of 100 km, there is a conventional line "Karman's line", which is considered to be the beginning of space.

Aurorae occur in the thermosphere. In this layer of the atmosphere, the solar wind interacts with magnetic field planets.

The last layer of the atmosphere is the Exosphere, an outer shell that stretches for thousands of kilometers. The exosphere is practically empty space, however, the number of atoms wandering here is an order of magnitude greater than in interplanetary space.

Man breathes air. Normal pressure is 760 millimeters of mercury. At an altitude of 10,000 m, the pressure is about 200 mm. rt. Art. At such a height, a person can probably breathe, at least not for a long time, but this requires preparation. The state will clearly be inoperable.

The gas composition of the atmosphere: 78% nitrogen, 21% oxygen, about a percent argon, everything else is a mixture of gases representing the smallest fraction of the total.