The role of the Earth's atmosphere
The atmosphere is the lightest geosphere of the Earth, nevertheless, its influence on many Earth processes is very great.
Let's start with the fact that it was thanks to the atmosphere that the origin and existence of life on our planet became possible. Modern animals cannot do without oxygen, and most plants, algae and cyanobacteria cannot do without carbon dioxide. Oxygen is used by animals for respiration, carbon dioxide is used by plants in the process of photosynthesis, due to which complex organic substances, such as various carbon compounds, carbohydrates, amino acids, fatty acids, necessary for the life of plants are created.
With the rise in altitude, the partial pressure of oxygen begins to decrease. What does it mean? This means that there are fewer and fewer oxygen atoms in each unit of volume. At normal atmospheric pressure, the partial pressure of oxygen in the human lungs (so-called alveolar air) is 110 mm. rt. Art., the pressure of carbon dioxide is 40 mm Hg. Art., and water vapor - 47 mm Hg. st .. When rising in altitude, the pressure of oxygen in the lungs begins to fall, and carbon dioxide and water remains at the same level.
Starting from an altitude of 3 kilometers above sea level, most people begin to oxygen starvation or hypoxia. A person has shortness of breath, increased heartbeat, dizziness, tinnitus, headache, nausea, muscle weakness, sweating, visual impairment, drowsiness. Working capacity is sharply reduced. At altitudes over 9 kilometers, human breathing becomes impossible and therefore it is strictly forbidden to be without special breathing apparatus.
The role of the atmosphere as a protector of our planet from ultraviolet and X-ray radiation from the Sun, cosmic rays, and meteors is important for the normal life of organisms on Earth. The overwhelming majority of radiation is trapped by the upper layers of the atmosphere - the stratosphere and mesosphere, resulting in such amazing electrical phenomena as auroras. The rest, a smaller part of the radiation, is scattered. Here, in the upper layers of the atmosphere, meteors also burn, which we can observe in the form of small "falling stars".
The atmosphere serves as a regulator for seasonal temperature fluctuations and diurnal smoothing, preventing the Earth from overheating during the day and cooling at night. The atmosphere, due to the presence of water vapor, carbon dioxide, methane and ozone in its composition, easily transmits the sun's rays, heating its lower layers and the underlying surface, but retains the return thermal radiation from the earth's surface in the form of long-wave radiation. This feature of the atmosphere is called the greenhouse effect. Without it, daily fluctuations in the temperatures of the lower layers of the atmosphere would reach colossal values: up to 200 ° C and would naturally make life impossible in the form in which we know it.
Different parts of the earth are heated unevenly. Low latitudes of our planet, i.e. regions with a subtropical and tropical climate receive much more heat from the Sun than medium and high regions with a temperate and arctic (Antarctic) type of climate. Continents and oceans are heated differently. While the former heats up and cools much faster, the latter absorb heat for a long time, but at the same time and also give it away for a long time. As you know, warm air is lighter than cold air, and therefore rises. Its place at the surface is taken by colder, heavier air. This is how the wind is formed and the weather is formed. And the wind, in turn, leads to the processes of physical and chemical weathering, the latter of which form exogenous landforms
With the rise in altitude, climatic differences between different regions of the globe begin to fade. And starting from an altitude of 100 km. atmospheric air is deprived of the ability to absorb, conduct and transfer thermal energy by convection. The only way to transfer heat is thermal radiation, i.e. heating of air by cosmic and sun rays.
In addition, only if there is an atmosphere on the planet, the water cycle in nature, precipitation and the formation of clouds are possible.
The water cycle is the process of cyclic movement of water within the earth's biosphere, consisting of the processes of evaporation, condensation and precipitation. There are 3 levels of the water cycle:
Large, or world, cycle - water vapor formed above the surface of the oceans is carried by winds to the continents, falls there in the form of precipitation and returns to the ocean in the form of runoff. In this process, the quality of water changes: during evaporation, salty sea water turns into fresh water, and polluted water is purified.
Small, or oceanic, cycle - water vapor formed over the surface of the ocean condenses and falls as precipitation back into the ocean.
Intracontinental circulation - water that has evaporated above the land surface falls back onto land in the form of atmospheric precipitation.
It is also worth noting that precipitation becomes possible only if the so-called condensation nuclei - the smallest solid particles. If there were no such particles in the earth's atmosphere, then no precipitation would have occurred.
And the last thing I wanted to say about the role of the Earth's atmosphere is that only thanks to it on our planet, the propagation of sounds and the emergence of aerodynamic lift is possible. Dead silence reigns on planets lacking or having an atmosphere of low power. A person on such celestial bodies is literally speechless. In the absence of an atmosphere, it becomes impossible to control aerodynamic flight, which is replaced by ballistic flight.
In the existence of the Earth, the significance of the atmosphere is enormous. If you deprive our planet of the atmosphere, all living organisms will die. Its effect can be compared to the role of glass in a greenhouse, which allows light to pass through and does not release heat back. Thus, the atmosphere protects the Earth's surface from excessive heating and cooling.
The value of the atmosphere for humans
The air shell of the globe is a protective layer that saves all living things from corpuscular and short-wave solar radiation. In the atmospheric environment, all weather conditions arise in which a person lives and works. Meteorological stations are being created to study this earth's shell. Around the clock, in any weather, meteorologists observe the state of the lower atmospheric layer and record their observations. Several times a day (in some regions every hour), the stations measure temperature, humidity, pressure, detect the presence of cloudiness, wind direction, any sound and electrical phenomena, measure the wind speed and the amount of precipitation. Meteorological stations are scattered throughout our planet: in the polar regions, in the tropics, in the highlands, and on the tundra. On the seas and oceans, observations are also made from stations located on specially constructed devices on ships of special purpose. 
Measurement of environmental parameters
Since the beginning of the twentieth century, measurements of the parameters of the state of the environment in a free atmosphere have begun. For this purpose, radiosondes are launched. They are able to rise to an altitude of 25-35 km and, using radio equipment, send data on pressure, temperature, wind speed and air humidity to the Earth's surface. In the modern world, they often resort to the use of meteorological satellites and rockets. They are equipped with television sets that accurately reproduce images of the planet's surface and clouds.
Related materials:
The world around us is formed from three very different parts: earth, water and air. Each of them is unique and interesting in its own way. Now we will only talk about the last of them. What is atmosphere? How did it come about? What does it consist of and what parts is it divided into? All of these questions are extremely interesting.
The very name "atmosphere" is formed from two words of Greek origin, translated into Russian they mean "steam" and "ball". And if you look at the exact definition, you can read the following: "The atmosphere is the air shell of the planet Earth, which rushes along with it in outer space." It developed in parallel with the geological and geochemical processes that took place on the planet. And today all processes in living organisms depend on it. Without an atmosphere, the planet would become a lifeless desert like the moon.
What does it consist of?
The question of what an atmosphere is and what elements are included in it has interested people for a long time. The main components of this shell were already known in 1774. They were installed by Antoine Lavoisier. He found that the composition of the atmosphere was largely composed of nitrogen and oxygen. Over time, its components have been refined. And now it is known that it contains many other gases, as well as water and dust.
Let's take a closer look at what makes up the Earth's atmosphere near its surface. The most common gas is nitrogen. It contains slightly more than 78 percent. But, despite such a large amount, nitrogen is practically inactive in the air.
The next most important and most important element is oxygen. This gas contains almost 21%, and it just shows a very high activity. Its specific function is to oxidize dead organic matter, which decomposes as a result of this reaction.
Gases with a low content, but an important value
The third gas that is part of the atmosphere is argon. Its a little less than one percent. It is followed by carbon dioxide with neon, helium with methane, krypton with hydrogen, xenon, ozone and even ammonia. But there are so few of them that the percentage of such components is equal to hundredths, thousandths and millionths. Of these, only carbon dioxide plays a significant role, since it is the building material that plants need for photosynthesis. Its other important function is to keep out radiation and absorb some of the sun's heat.
Another small but important gas, ozone, exists to trap ultraviolet radiation from the sun. Thanks to this property, all life on the planet is reliably protected. On the other hand, ozone affects the temperature of the stratosphere. Due to the fact that it absorbs this radiation, the air heats up.
The constancy of the quantitative composition of the atmosphere is maintained by non-stop stirring. Its layers move both horizontally and vertically. Therefore, anywhere in the world there is enough oxygen and there is no excess of carbon dioxide.
What else is in the air?
It should be noted that vapor and dust can be found in the air. The latter consists of pollen and soil particles, in the city they are joined by impurities of solid emissions from exhaust gases.
But there is a lot of water in the atmosphere. Under certain conditions, it condenses and clouds and fog appear. In fact, they are one and the same, only the former appear high above the surface of the Earth, and the latter creeps along it. Clouds take on a variety of shapes. This process depends on the height above the Earth.
If they formed 2 km above the land, then they are called layered. It is from them that rain or snow falls on the ground. Cumulus clouds form above them up to an altitude of 8 km. They are always the most beautiful and picturesque. They are the ones who are looked at and wonder what they look like. If such formations appear in the next 10 km, they will be very light and airy. Their name is feathery.
What layers is the atmosphere divided into?
Although they have very different temperatures from each other, it is very difficult to say at what specific height one layer begins and the other ends. This division is very arbitrary and approximate. However, layers of the atmosphere still exist and perform their functions.
The lowest part of the air envelope is called the troposphere. Its thickness increases as it moves from the poles to the equator from 8 to 18 km. This is the warmest part of the atmosphere, as the air in it heats up from the earth's surface. Most of the water vapor is concentrated in the troposphere, so clouds form in it, precipitation falls, thunderstorms thunder and winds blow.
The next layer is about 40 km thick and is called the stratosphere. If the observer moves to this part of the air, he will find that the sky has turned purple. This is due to the low density of the substance, which practically does not scatter the sun's rays. It is in this layer that jet planes fly. All open spaces are open for them, since there are practically no clouds. Inside the stratosphere, there is a layer of large amounts of ozone.
It is followed by the stratopause and the mesosphere. The latter is about 30 km thick. It is characterized by a sharp decrease in air density and temperature. The sky is black for the observer. Here you can even watch the stars during the day.
Layers with little or no air
The structure of the atmosphere continues with a layer called the thermosphere - the longest of all the others, its thickness reaches 400 km. This layer is characterized by an enormous temperature, which can reach 1700 ° C.
The last two spheres are often combined into one and are called the ionosphere. This is due to the fact that reactions with the release of ions take place in them. It is these layers that make it possible to observe such a natural phenomenon as the northern lights.
The next 50 km from the Earth is allocated to the exosphere. This is the outer shell of the atmosphere. It scatters air particles into space. Weather satellites usually move in this layer.
The Earth's atmosphere ends with the magnetosphere. It was she who sheltered most of the artificial satellites of the planet.
After all that has been said, there should be no questions about what the atmosphere is. If there are doubts about its necessity, then it is easy to dispel them.
The meaning of the atmosphere
The main function of the atmosphere is to protect the planet's surface from overheating in the daytime and excessive cooling at night. The next importance of this shell, which no one will dispute, is to supply oxygen to all living things. Without this, they would suffocate.
Most meteorites burn up in the upper layers, never reaching the Earth's surface. And people can admire flying lights, mistaking them for shooting stars. Without the atmosphere, the entire Earth would be strewn with craters. And the protection from solar radiation has already been mentioned above.
How does a person affect the atmosphere?
Very negative. This is due to the growing activity of people. The main share of all negative aspects falls on industry and transport. By the way, it is cars that emit almost 60% of all pollutants that penetrate into the atmosphere. The remaining forty are divided between energy and industry, as well as waste disposal industries.
The list of harmful substances that replenish the composition of the air every day is very long. Due to transport in the atmosphere, there are: nitrogen and sulfur, carbon, blue bream and soot, as well as a strong carcinogen that causes skin cancer - benzopyrene.
The industry accounts for the following chemical elements: sulfur dioxide, hydrocarbon and hydrogen sulfide, ammonia and phenol, chlorine and fluorine. If the process continues, then soon the answers to the questions: “What is the atmosphere? What does it consist of? " will be completely different.
6.2. The meaning and structure of the atmosphere
If water, which has long been in short supply, was called the "resource of life", then the air was remembered only in our urbanized era. Recall that a person can live without food for several tens of days, and without air - only up to 5-7 minutes. In addition, a person needs clean air, which, especially in cities and industrial centers, is lacking.
The meaning of the atmosphere. Atmospheric air is the most important natural resource, its appointment ( for the Earth and humanity ):
To supply people, flora and fauna with vital gas elements (oxygen, carbon dioxide);
Soften temperature drops (air is a poor conductor of heat and cold), i.e. to provide thermoregulation on the planet;
Protect the Earth's surface from cosmic, radiation and ultraviolet solar radiation;
Protect the Earth from meteorites and other cosmic bodies, the overwhelming mass of which burns up in the atmosphere;
Provide production anthropogenic processes with oxygen, nitrogen, hydrogen and neutral gases.
The atmosphere "warms" our planet by absorbing the heat emitted by the Earth into world space, and partially returning it in the form of oncoming radiation. The atmosphere scatters the sun's rays, resulting in a gradual transition from light to shadow (twilight). At night, it emits light rays and serves as a source of illumination of the earth's surface.
The night glow of the atmosphere (luminescence) is the glow of rarefied air gases at altitudes from 80 to 300 km. It provides 40 - 45% of the total illumination of the earth's surface on a moonless night, while starlight is about 30%, and the light scattered by interstellar dust accounts for the remaining 25 - 30%. A variety of atmospheric glow are auroras. On Earth, they are observed at high latitudes only at night in the absence of clouds. From space, auroras are always visible, and at the same time over large areas.
The structure of the atmosphere. In the composition of the atmosphere, several layers are distinguished - spheres, between which there are no sharply defined boundaries.
1. Troposphere - lower main layer of the atmosphere. It is the most well studied. The height of the troposphere reaches 10 km above the poles, 12 km in temperate latitudes and up to 18 km above the equator.
The troposphere contains more than 4/5 of the total mass of atmospheric air. Various weather phenomena are most clearly manifested in it. It is known that with a rise of 1 km, the air temperature in this layer decreases by more than 6 degrees... This happens because the air lets the sun's rays reach the surface of the Earth, which heats it up. The layers of the atmosphere adjacent to the Earth also heat up from the earth's surface.
In winter, the surface of the Earth is greatly cooled, which is facilitated by the snow cover, which reflects most of the sun's rays. For this reason, the air at the surface of the Earth turns out to be colder than at the top, that is, the so-called inversion of temperature. Temperature inversion is often observed at night as well.
In summer, the surface of the Earth is strongly and unevenly heated by the sun's rays. Air vortices rise from the most heated parts of it. The rising air is replaced by air from the side of less heated areas of the Earth, which in turn is replaced by air from the upper layers of the atmosphere. Arises convection, which causes vertical mixing of the atmosphere. Convection helps to disperse fog and reduce dustiness in the lower atmosphere.
In the upper layers of the troposphere at an altitude of 12 - 17 km, during the flight of aircraft, white cloud trails are often formed, which are clearly visible from a long distance. These footprints are called condensing, or traces inversion. The main cause of condensation trails is the condensation, or sublimation of water vapor that enters the atmosphere with the exhaust gases of aircraft engines, since when kerosene is burned in an aircraft engine, water vapor is formed.
To burn 1 kg of fuel in an engine, about 11 kg of atmospheric air is consumed, and about 12 kg of exhaust gases are formed, containing almost 1.4 kg of water vapor.
2. Stratosphere is located above the troposphere up to an altitude of 50-55 km. It contains less than 20% of the mass of all atmospheric air. In this layer, there is an insignificant movement of gases and an increase in temperature occurs with height (up to 0 0 С at the upper boundary).
The lower part of the stratosphere is a powerful trapping layer, under which water vapor, ice crystals and other solid particles accumulate. Relative humidity here is always close to 100%.
In the stratosphere situated ozone layer, reflecting cosmic radiation, which is harmful to life, and partly ultraviolet rays of the Sun. Highest concentration ozone exists at an altitude of 15-35 km, where free oxygen under the influence of solar radiation turns into ozone .
3. Mesosphere extends above the stratosphere at an altitude of approximately 50 to 80 km. It accounts for less than 1% of the air. It is characterized by a decrease in temperature with increasing altitude, from approximately 0 ° С at the border with the stratosphere to -90 ° С in the upper layers of the mesosphere.
4. Ionosphere located above the mesosphere. It is characterized by a significant content of atmospheric ions and free electrons. In the ionosphere, under the action of ultraviolet and X-ray solar radiation, ionization of highly rarefied air, as well as cosmic radiation, occurs, which cause the decomposition of atmospheric gas molecules into ions and electrons. Ionization is especially intense at an altitude of 80 to 400 km. The ionosphere promotes the propagation of radio waves. The upper boundary of the ionosphere is the outer part of the Earth's magnetosphere. The ionosphere is often called thermosphere.
atmosphere environmental pollution
Atmospheric air is an essential natural resource. Oxygen, which is part of the atmosphere, is used by living organisms during respiration. It is used for the combustion of any fuel in various production plants and engines. The atmosphere is an important route of communication used by aviation.
The main consumers of air in nature are the flora and fauna of the Earth. It is estimated that the entire air ocean passes through terrestrial organisms in about ten years.
The atmosphere is permeated with powerful solar radiation, which regulates the thermal regime of the Earth, it contributes to the redistribution of heat around the globe. The radiant energy of the Sun is practically the only source of heat for the Earth's surface. This energy is partially absorbed by the atmosphere. The energy that reaches the Earth is partly absorbed by soil and water and partly reflected from their surface into the atmosphere. It is not difficult to imagine what the temperature regime of the Earth would be if there was no atmosphere: at night and in winter it would be strongly cooled due to solar radiation, and in summer and during the day it would overheat due to solar radiation, as happens on the Moon, where there is no atmosphere.
Thanks to the atmosphere on Earth, there are no abrupt transitions from frost to heat and vice versa. ...
If the Earth were not circled by the atmosphere, then during one day the amplitude of temperature fluctuations would reach 200 C: during the day about +100 C, at night about 100 C. An even greater difference would be between winter and summer temperatures. But thanks to the atmosphere, the average temperature of the Earth is about + 15 "C.
The atmosphere is a reliable shield that saves all organisms living on Earth from destructive ultraviolet, X-ray and cosmic rays, which are partially scattered and partially absorbed in its upper layers.
The exchange of substances between the Earth and the Cosmos takes place through the atmosphere. In this case, the Earth loses the lightest gases - hydrogen and helium and receives cosmic dust and meteorites. The atmosphere protects us from stellar debris. In most cases, the size of meteorites is no larger than a pea; they, under the influence of gravity, crash into the atmosphere at a tremendous speed of 11-64 km / s, heat up due to friction against the air and mostly burn up at an altitude of 60-70 km from the Earth's surface. The radiant energy of the Sun is practically the only source of heat for the Earth's surface. This energy is partially absorbed by the atmosphere. The energy that reaches the Earth is partly absorbed by soil and water and partly reflected from their surface into the atmosphere. It is not difficult to imagine what the temperature regime of the Earth would be if there was no atmosphere: at night and in winter it would be strongly cooled due to solar radiation, and in summer and during the day it would overheat due to solar radiation, as happens on the Moon, where there is no atmosphere.
Thanks to the atmosphere on Earth, there are no abrupt transitions from frost to heat and vice versa. If the Earth were not circled by the atmosphere, then during one day the amplitude of temperature fluctuations would reach 200 C: during the day about +100 C, at night about 100 C. An even greater difference would be between winter and summer temperatures. But thanks to the atmosphere, the average temperature of the Earth is about + 15 "C.
The ozone shield is of the utmost importance. It is located in the stratosphere, at an altitude of 20-50 km from the Earth's surface. The total amount of ozone in the atmosphere is estimated at 3.3 billion tons. The thickness of this layer is relatively small: from 2 mm at the equator to 4 mm at the poles under normal conditions. The main value of the ozone shield is to protect living organisms from ultraviolet radiation.
The atmosphere is a reliable shield that saves all organisms living on Earth from destructive ultraviolet, X-ray and cosmic rays, which are partially scattered and partially absorbed in its upper layers. The exchange of substances between the Earth and the Cosmos takes place through the atmosphere. In this case, the Earth loses the lightest gases - hydrogen and helium and receives cosmic dust and meteorites. ...
The atmosphere protects us from stellar debris. In most cases, the size of meteorites is no larger than a pea; they, under the influence of gravity, crash into the atmosphere at a tremendous speed of 11-64 km / s, heat up due to friction against the air and mostly burn up at an altitude of 60-70 km from the Earth's surface. The atmosphere plays a big role in the distribution of light. Air breaks the sun's rays into millions of small rays, scatters them and creates that uniform illumination that we are used to.
The presence of an air shell gives our sky a blue color, since the molecules of the main elements of air and various impurities contained in it scatter mainly rays with a short wavelength, that is, blue, blue, violet. Sometimes, due to the presence of impurities in the atmosphere, the color of the sky is not purely naked. As it rises upwards, the density and contamination of the air decreases, i.e. the amount of scattering particles, the color of the sky becomes darker, turns into a deep blue, and in the stratosphere - into black-violet. The atmosphere is the medium where sounds propagate. Without air, silence would reign on Earth. We would not hear each other, nor the noise of the sea, wind, forest, etc. ...
The ionosphere facilitates the transmission of radio signals and the propagation of radio waves.
For a long time, it was believed that air has no mass. Only in the 17th century it was proved that the mass of 1 m 3 of dry air, if weighed at sea level at a temperature of 0 ° C, is equal to 1293 g, and for every square centimeter of the earth's surface there is 1033 g of air.
The human palm experiences air pressure with a force of about 1471N, and the air presses on the entire human body with a force of 1471 * 103 N. We do not notice this weight only because all the tissues of our body are also saturated with air, which balances external pressure. When this balance is disturbed, our well-being worsens: the pulse quickens, lethargy, indifference, etc. appear. The same sensations are experienced by a person when climbing uphill or diving to great depths, as well as during takeoff and landing of an aircraft. Above, the air pressure and its mass decrease: at an altitude of 20 km, the mass of 1 m 3 of air is 43 g, and at an altitude of 40 km - 4 g. The radiant energy of the Sun is practically the only source of heat for the Earth's surface. This energy is partially absorbed by the atmosphere. The energy that reaches the Earth is partly absorbed by soil and water and partly reflected from their surface into the atmosphere. It is not difficult to imagine what the temperature regime of the Earth would be if there was no atmosphere: at night and in winter it would be strongly cooled due to solar radiation, and in summer and during the day it would overheat due to solar radiation, as happens on the Moon, where there is no atmosphere.
All processes developing in the atmosphere are carried out due to the energy of the Sun. Thanks to it, billions of tons of water evaporate from the Earth's surface every year. The atmosphere plays the role of moisture redistribution on the globe.
The physical properties and state of the atmosphere change: 1) in time - during the day, seasons, years; 2) in space - depending on the height above sea level, the latitude of the area and the distance from the ocean.
The atmosphere always contains a certain amount of impurities. Sources of pollution can be natural or man-made. Natural sources include: dust (plant, volcanic and space origin), dust storms, particles of sea salt, weathering products, fog, smoke and gases from forest and steppe fires, various products of plant, animal and microbiological origin, etc. Natural sources of pollution atmospheres are such a formidable natural phenomenon as volcanic eruptions. It is usually catastrophic. During volcanic eruptions, a huge amount of gases, water vapor, solid particles, ash and dust is emitted into the atmosphere, thermal pollution of the atmosphere occurs, since highly heated substances are thrown into the air. ...
Their temperature is such that they burn everything in their path. After the attenuation of volcanic activity, the general balance of gases in the atmosphere is gradually restored.
Large forest and steppe fires significantly pollute the atmosphere. They most often occur during dry years. The smoke from the fires spreads over vast areas. Dust storms occur in connection with the transfer of the smallest soil particles lifted from the earth's surface by a strong wind. Strong winds - tornadoes, hurricanes - lift large fragments of rocks into the air, but they do not stay in the air for a long time. During strong storms, up to 50 million tons of dust rises into the air. Dust storms are caused by drought, dry winds, which occur due to intensive plowing, cattle grazing, and deforestation. Dust storms are most frequent in steppe, semi-desert and desert regions. Catastrophic phenomena associated with volcanic eruptions, fires and dust storms lead to the emergence of a light-shielding screen around the Earth, which somewhat alters the thermal balance of the planet. But these phenomena are mostly local in nature. Air pollution associated with weathering and decomposition of organic matter is of a very insignificant local character. ...
Natural sources of pollution are either distributed, such as the fallout of cosmic dust, or short-term spontaneous ones, for example, forest and steppe fires, volcanic eruptions, etc. The level of air pollution from natural sources is background and changes little over time. Artificial pollution is the most dangerous for the atmosphere. The most stable zones with high concentrations of pollution arise in places of active human activity. Anthropogenic pollution is distinguished by a variety of types and a variety of sources. Natural sources of air pollution are such a formidable natural phenomenon as volcanic eruptions. It is usually catastrophic. During volcanic eruptions, a huge amount of gases, water vapor, solid particles, ash and dust is emitted into the atmosphere, thermal pollution of the atmosphere occurs, since highly heated substances are thrown into the air. Their temperature is such that they burn everything in their path. After the attenuation of volcanic activity, the general balance of gases in the atmosphere is gradually restored. ...
Air pollution is not a new problem. More than two centuries ago, air pollution in major industrial centers in many European countries became a serious concern. However, for a long time, these pollution had a local character. Smoke and soot polluted relatively small areas of the atmosphere and were easily diluted with a mass of clean air at a time when there were few factories and factories and the use of chemical elements was limited. If at the beginning of the 20th century. 19 chemical elements were used in industry, about 50 elements were already used in the middle of the century, but at present - almost all elements of the periodic table. This significantly affected the composition of industrial emissions and led to a qualitatively new pollution of the atmosphere with aerosols of heavy and rare metals, synthetic compounds that do not exist and are not formed in nature by radioactive, carcinogenic, bacteriological and other substances.
The rapid growth of industry and transport has meant that such an amount of emissions can no longer be dispersed. Their concentration increases, which entails dangerous and even fatal consequences for the biosphere. This problem became especially acute in the second half of the 20th century, that is, during the period of the scientific and technological revolution, characterized by extremely high rates of growth in industrial production, generation and consumption of electricity, production and use of a large number of vehicles.
The main pollution of the atmosphere is created by a number of industries, motor transport and heat power engineering. Moreover, their participation in atmospheric pollution is distributed as follows: ferrous and non-ferrous metallurgy, oil production, petrochemistry, production of building materials, chemical industry - 30%; heat power - 30%, motor transport - 40%.
The most common toxic substances that pollute the atmosphere are: carbon monoxide CO, sulfur dioxide SO 2, carbon dioxide CO 2, nitrogen oxides NO x, hydrocarbons C p N m and dust. The approximate relative composition of harmful substances in the atmosphere of large industrial cities is: CO - 45%, SO - 18%, CH - 15%, dust - 12%. ...
In addition to these substances, other more toxic substances are found in polluted atmospheric air, but in smaller quantities. So, for example, ventilation emissions from electronics factories contain vapors of hydrofluoric, sulfuric, chromic and other mineral acids, organic solvents, etc. Currently, there are more than 500 harmful substances that pollute the atmosphere, and their number is increasing. Artificial pollution is the most dangerous for the atmosphere. The most stable zones with high concentrations of pollution arise in places of active human activity. Anthropogenic pollution is distinguished by a variety of types and a variety of sources. Natural sources of air pollution are such a formidable natural phenomenon as volcanic eruptions. It is usually catastrophic. During volcanic eruptions, a huge amount of gases, water vapor, solid particles, ash and dust is emitted into the atmosphere, thermal pollution of the atmosphere occurs, since highly heated substances are thrown into the air. Their temperature is such that they burn everything in their path. After the attenuation of volcanic activity, the general balance of gases in the atmosphere is gradually restored.
