Environmental quality
The quality of the environment is the state of natural and human-transformed ecosystems that preserve their ability
In natural ecosystems, the quality of the natural environment is ensured by the action of the laws of nature, in transformed ones - by observing the measure of compliance of the natural environment with the needs of living organisms and the ecological interests of society.
Pollution is the presence of physical, chemical, informational or biological agents or the excess of the natural average long-term level (within the limits of its extreme fluctuations) of the concentration of the listed agents in the environment at the considered time, often leading to negative consequences.
Pollution is everything that is in the wrong place, at the wrong time and in the wrong amount, which is natural for nature, brings it out of balance, differs from the usually observed norm
Pollution can occur as a result of natural causes (natural pollution) and under the influence of human activities (anthropogenic pollution). The pollution level is controlled by MPC values \u200b\u200band other standards.
The specificity of each type of production activity also creates certain types of environmental pollutants.
To assess the impact of pollutants on environmental objects, it is necessary to know the parameters and indicators for which it is necessary to assess pollution. Their composition and contaminating properties are established by physical and chemical analysis, which is based on quantitative chemical analysis.
The environmental quality index is a quantitative indicator of the state of the environment, which is differently expressed depending on the purpose of the assessment: in points or in absolute units (for example, in MPC and other characteristics of the degree of pollution by an individual substance or group of substances).
The analysis of the composition of pollutants and their properties, as well as the chemical composition of environmental objects should be carried out according to uniform methods by specialized accredited laboratories approved for the purposes of state environmental control.
Effective regulation of the quality of the environment is based on adequate information on pollution levels and changes in ecosystems under the influence of pollution, based on data obtained as a result of environmental monitoring.
The practice of environmental regulation, which developed rapidly in the 70s - 80s. XX century., Identified three main types of rationing:
Sanitary and hygienic (MPC, OBUV);
Production and economic [maximum permissible emissions (MPE), VSV, MPD, PNOLRO];
Ecosystem (ecological standard).
Atmospheric air condition
The atmosphere is a huge air system. The lower layer (troposphere) is 8 km thick at polar and 18 km at equatorial latitudes (80% of the air), the upper layer (stratosphere) is up to 55 km thick (20% of the air). The atmosphere is characterized by gaseous chemical composition, humidity, composition of suspended solids, and temperature. Under normal conditions, the chemical composition of air (by volume) is as follows: nitrogen - 78.08%; oxygen - 20.95%; carbon dioxide - 0.03%; argon - 0.93%; neon, helium, krypton, hydrogen - 0.002%; ozone, methane, carbon monoxide and nitrogen oxide - ten thousandths of a percent.
The total amount of free oxygen in the atmosphere is 1.5 to 10 degrees.
The purpose of the atmosphere in the Earth's ecosystem is to provide humans, flora and fauna with vital gas elements (oxygen, carbon dioxide), to protect the Earth from meteorite impact, cosmic radiation and solar irradiation. In the course of its existence, the atmosphere undergoes the following changes:
Irrevocable collection of gas elements;
Temporary withdrawal of gas elements;
Contamination with gas impurities destroying its gas structure;
Suspended matter pollution;
Heating;
Replenishment with gas elements;
Self-cleaning.
Oxygen is the most important component of air for humans. With a lack of oxygen, a person develops compensatory phenomena: breathing quickens, blood flow accelerates, etc. For 60 years of a person's life in the city, 200 g of harmful chemicals, 16 g of dust, 0.1 g of metals pass through his lungs. The most dangerous substances for humans include the carcinogen benz (a) pyrene (a product of thermal decomposition of raw materials and combustion of fuel), formaldehyde and phenol.
In the process of burning fossil fuels (coal, oil, natural gas, wood), oxygen is intensively consumed and the atmosphere is polluted with carbon dioxide, sulfur compounds, and suspended solids. In the world, 10 billion tons of standard fuel are burned annually, while, along with the organized ones, unorganized combustion processes occur: fires in everyday life, in the forest, in coal warehouses, ignition of natural gas outlets, fires in oil fields and during fuel transportation. For all forms of fuel combustion, for obtaining metallurgical and chemical products, for additional oxidation of various wastes, 10 - 20 billion tons of oxygen are annually consumed. By the end of the century, this value increases to 50 billion tons. The increase in oxygen consumption caused by the intensification of human economic activity is at least 10 - 16% of the annual biogenic formation.
Automotive transport consumes oxygen in the air to support the combustion process in engines; pollutes the atmosphere with carbon dioxide, dust, suspended products of gasoline combustion (lead, sulfur dioxide, etc.). About 13% of all air pollution is associated with road transport. They are reduced by improving the fuel system of cars, using electric motors. Natural gas, hydrogen or low sulfur gasoline, discontinuation of leaded gasoline, catalysts and exhaust filters.
According to Roshydromet, which monitors air pollution, in 2001, in 207 cities of the country with a population of 64.5 million people, the average annual concentrations of harmful substances in the air exceeded the MPC (in 2000 - 202 cities).
In 48 cities with a population of over 23 million people, the maximum one-time concentrations of various harmful substances of more than 10 MPC were recorded (in 2000 - in 40 cities).
In 115 cities with a population of almost 50 million people, the air pollution index (API) exceeded 7, that is, the level of air pollution was assessed as high and very high (in 2000 - 98 cities). The priority list of cities with the highest level of air pollution in Russia (with an air pollution index equal to or greater than 14) in 2001 included 31 cities with a population of more than 15 million people (in 2000 - cities).
In 2001, in comparison with the previous year, in terms of all indicators of air pollution, the number of cities and, accordingly, the number of the population, exposed not only to a high, but also an ever-increasing effect of air pollutants, increased.
The observed changes occur not only as a result of an increase in industrial emissions with an increase in industrial production, but also as a result of an increase in the car park in cities, the burning of huge amounts of fuel at thermal power plants, traffic congestion and prolonged idling of engines, in the absence of waste disposal equipment on cars. gases. In recent years, many cities have seen a significant reduction in environmentally friendly public transport means - trams and trolleybuses - due to an increase in the fleet of route taxis.
In 2001, the list of cities with a very high level of air pollution, as before, included 10 cities - centers of ferrous and nonferrous metallurgy, oil and oil refining industries.
The state of atmospheric air in cities by federal districts is characterized as follows.
In the Central Federal District in 35 cities, the average annual concentration of harmful impurities exceeded 1 MPC. In 16 cities with a population of 8 433 thousand people, the level of pollution was high (API was equal to or more than 7). In the cities of Kursk, Lipetsk and in the southern part of Moscow, this indicator was very high (API is equal to or more than 14), and therefore they were included in the number of cities with the highest level of air pollution.
In the Northwestern Federal District, in 24 cities, the average annual concentrations of harmful impurities exceeded 1 MPC, and in four cities, their maximum one-time concentrations exceeded 10 MPC. In 9 cities with a population of 7,181 thousand people, the level of pollution was high, and in the city of Cherepovets - very high.
In the Southern Federal District, in 19 cities, the average annual concentrations of harmful substances in the ambient air exceeded 1 MPC, and in four cities their maximum one-time concentrations were more than 10 MPC. The high level of air pollution was in 19 cities with a population of 5 388 thousand people. A very high level of air pollution was noted in Azov, Volgodonsk, Krasnodar and Rostov-on-Don, in connection with which they are classified among the cities with the most polluted air basin
In the Volga Federal District in 2001, the average annual concentration of harmful impurities in the air exceeded 1 MPC in 41 cities. The maximum one-time concentration of harmful substances in the air was more than 10 MPC in 9 cities. The level of air pollution was high in 27 cities with a population of 11 801 thousand people, and very high in Ufa (classified as one of the cities with the highest level of air pollution).
In the Ural Federal District, the average annual concentration of harmful impurities in the air exceeded 1 MPC in 18 cities. The maximum one-time concentrations were more than 10 MPC in 6 cities. A high level of air pollution was in 13 cities with a population of 4,758 thousand people, and Yekaterinburg, Magnitogorsk, Kurgan and Tyumen were included in the list of cities with the highest level of air pollution.
In the Siberian Federal District, in 47 cities, the average annual concentrations of harmful impurities in the atmospheric air exceeded 1 MPC, and in 16 cities, the maximum one-time concentrations were more than 10 MPC. A high level of air pollution was noted in 28 cities with a population of 9 409 people, and a very high level in the cities of Bratsk, Biysk, Zima, Irkutsk, Kemerovo, Krasnoyarsk, Novokuznetsk, Omsk, Selenginsk, Ulan-Ude, Usolye-Sibirskoye, Chita and Shelekhov. Thus, the Siberian Federal District in 2001 was the leader both in the number of cities in which the average annual MPC norms were exceeded, and in the number of cities with the highest level of air pollution.
In the Far Eastern Federal District, the average annual concentration of harmful impurities exceeded 1 MPC in 23 cities, the maximum one-time concentrations were more than 10 MPC in 9 cities. A high level of air pollution was noted in 11 cities with a population of 2,311 thousand people. The cities of Magadan, Tynda, Ussuriysk, Khabarovsk and Yuzhno-Sakhalinsk are among the cities with the highest level of air pollution.
In the context of increasing industrial production, mainly on morally and physically obsolete equipment in the basic sectors of the economy, as well as with a steadily growing number of cars, a further deterioration in the quality of atmospheric air in cities and industrial centers of the country should be expected.
According to the data of the joint program for monitoring and evaluating the long-range transport of air pollutants in Europe, presented in 2001, in the European Territory of Russia (ETR), the total deposition of oxidized sulfur and nitrogen amounted to 2,038.2 thousand tons, 62.2% this amount is transboundary deposition. The total fallout of ammonia in the EPR amounted to 694.5 thousand tons, of which 45.6% was transboundary fallout.
The total fallout of lead in the EPR amounted to 4,194 tons, including 2,612 tons, or 62.3%, - transboundary fallouts. The ETR received 134.9 tons of cadmium, of which 94.8 tons, or 70.2% - as a result of cross-border receipts. Deposits of mercury amounted to 71.2 tons, of which 67.19 tons, or 94.4%, were transboundary inputs. A significant share of the contribution to the transboundary pollution of the territory of Russia with mercury (almost 89%) is made by natural and anthropogenic sources located outside the European region.
Deposition of benzo (a) pyrene exceeded 21 tons, of which 16 tons, or more than 75.5%, are transboundary fallouts.
Despite the measures taken to reduce emissions of harmful substances by the Parties to the Convention on Long-Range Transboundary Air Pollution (1979), the transboundary depositions of oxidized sulfur and nitrogen, lead, cadmium, mercury and benzo (a) pyrene on the EPR exceed those from Russian sources.
The state of the ozone layer of the Earth over the territory of the Russian Federation in 2001 turned out to be stable and very close to the norm, which is quite remarkable against the background of a strong decrease in the total ozone content observed in the period from 1988 to 1997.
Roshydromet data showed that until now ozone-depleting substances (chlorofluorocarbons) have not played a decisive role in the observed interannual variability of the total ozone content, which occurs under the influence of natural factors.
About 65% of all emissions occur in the European part of Russia, as a result of the industrial activity of the Ural, Northern and Central regions. The leader is the Krasnoyarsk Territory, the second is the Sverdlovsk Region. The largest contribution to air pollution is made by the electric power industry, non-ferrous and ferrous metallurgy, oil production and oil refining, coal and gas industries, and mechanical engineering. (fig. 2)
The largest volume of air pollution emissions per capita is in the Yamalo-Nenets Autonomous Okrug (1079 kg), the largest amount of toxic waste is in the Kemerovo Region (4752 kg). (fig. 1)
Industrial plants should be located on the leeward side so that their air emissions do not move to residential areas of the city. A “heat cap” is being created in the city, due to the special circulation of air masses and concentrating pollution in itself. The temperature difference between the city and the surrounding countryside can be as high as 8 ° C.
The downward movement of air currents in the anticyclone leads to the accumulation of pollution in the surface layers of the atmosphere. For this reason, the ultra-high concentration of industrial enterprises in Kuzbass (in a closed basin relief) has led to particularly difficult living conditions for the population. In a cyclone, the air is actively mixing and rising to the upper atmosphere, spreads over long distances. At the same time, the degree of local pollution decreases, but the pollution of vast territories occurs.
Cities with the highest levels of air pollution in 1999
| City | Substances that determine the high level of air pollution |
|---|---|
| Balakovo | Carbon disulfide, formaldehyde, nitrogen dioxide |
| Biysk | Formaldehyde, suspended solids, nitrogen dioxide |
| Bratsk | Formaldehyde, hydrogen fluoride, carbon disulfide, nitrogen dioxide |
| Ekaterinburg | Formaldehyde, benz (a) pyrene, acrolein |
| Irkutsk | Formaldehyde, suspended solids, nitrogen dioxide |
| Kemerovo | Carbon disulfide, ammonia, formaldehyde, soot |
| Krasnoyarsk | Benz (a) pyrene, suspended solids, chlorine |
| Krasnodar | Phenol, formaldehyde, suspended solids |
| Lipetsk | Phenol, ammonia, formaldehyde, nitrogen dioxide |
| Magadan | Phenol, formaldehyde, nitrogen dioxide |
| Magnitogorsk | Benz (a) pyrene, phenol, suspended solids |
| Moscow (separate large areas) | Ammonia, nitrogen dioxide, formaldehyde, |
| Novokuznetsk | Formaldehyde, suspended solids, hydrogen fluoride, nitrogen dioxide |
| Novorossiysk | Nitrogen dioxide, benz (a) pyrene, suspended, substances |
| Omsk | Formaldehyde, acetaldehyde, carbon black |
| Rostov-on-Don | Nitrogen dioxide, formaldehyde, suspended solids |
| Selenginsk | Formaldehyde, phenol, carbon disulfide, methyl mercaptan |
| Tyumen | Suspended solids, formaldehyde, lead |
| Ulan-Ude | Suspended solids, formaldehyde, nitrogen dioxide |
| Khabarovsk | Benz (a) pyrene, sulfur dioxide, nitrogen dioxide, formaldehyde, ammonia |
| Chita | Benz (a) pyrene, formaldehyde, suspended solids, nitrogen dioxide |
| Yuzhno-Sakhalinsk | Soot, suspended solids, nitrogen dioxide |
Energy - 25% of all pollutant emissions. Up to 70% of electricity in Russia is generated at thermal power plants that use coal, the combustion of which releases sulfur and sulfuric anhydrides, fluorides and toxic impurities of arsenic and silicon dioxide into the atmosphere. Pollution also comes from waste water from thermal power plants: vanadium, nickel, fluorine, phenols and oil products. There is also a factor of thermal pollution, because during the operation of turbines, the waste steam is cooled by water, which then enters the water bodies heated by 8-12 ° C. Coal-fired thermal power plants create radiation pollution - radioactive elements and their decay products have been found in fly ash. The reason is that coal contains the radioactive isotope of carbon C-14, impurities of potassium-40, uranium-238, thorium-232 and their decay products.
Ferrous metallurgy In 2000, emissions of harmful substances amounted to 2396 thousand tons. Discharge of polluted waste water amounted to 761.1 million m². During the year, 31,941.7 toxic wastes were generated. In steel production, oxygen is used to maintain the reaction. The process is accompanied by intense emission of flue gases containing carbon monoxide. Also, the waste gases contain sulfur dioxide, because iron ores contain sulfur compounds. Pollution from a metallurgical plant spreads over 15-25 km. The production of iron and steel in Russia is accompanied by the formation of more than 70 million tons of metallurgical slag, of which half is used.
Non-ferrous metallurgy When producing 1 ton of aluminum, about 38-47 kg of fluorine is consumed, with 65% being released into the atmosphere. Particularly dangerous are the emissions of highly toxic metal compounds: lead, mercury, copper, cadmium, zinc and a large amount of firing gases containing sulfur and fluorine compounds. The second pollutant after heat power engineering is sulfur dioxide. Moreover, the content of valuable components in slags is often higher than in the original ores.
Refining and petrochemical industry More than 4 billion oil is produced in the world, the losses of which during extraction, transportation and processing are 50 million tons. The process of air pollution begins already during production due to the release of associated gases containing hydrogen sulfide. During oil refining, sulfur-containing compounds are converted into sulfur dioxide, which is found around the refineries within a radius of 12-20 km. In addition to hydrogen sulfide and sulfur dioxide, petrochemical industries saturate the atmosphere with hydrocarbons, methanol, alkylnitrile, acetonitrile, dichloroethene and chloroethene, organic acids and anhydrides, oxides of sulfur, nitrogen, carbon, and carbon disulfide.
Chemical industry It pollutes the atmosphere with sulfur compounds (SO2, SO3, H2SO4, H2S, CS2, mercaptans), nitrogen (NO, NO2, NH3, HNO2, HNO3, etc.), chlorine, fluorine. It emits carbon monoxide, nitrogen dioxide, sulphurous anhydride, hydrogen sulfide, chlorides and fluorides into the atmosphere.
Automobile transport - the main pollutant of the atmosphere in cities. Emissions from automobile engines contain carbon monoxide and dioxide, sulfur dioxide, hydrocarbons, nitrogen oxides, lead compounds, dust, soot. (Fig. 3) In addition to being polluted by toxic exhaust, the car raises dust clouds containing silicon, iron oxide, barium. One rubber each car dissipates about 10 kg.
A large share of air pollution is contributed by building materials industry, using annually about 2 billion tons of mineral raw materials. At all stages of the production of building materials, dust is emitted, which is varied in composition and physical and chemical properties. Dust from cement plants is a source of pollution with heavy metals.
Studies have shown that in terms of the quality of atmospheric air, the East Siberian region is the most unfavorable for living. Highest mortality rate: 14.9 per 1,000. For each district, there are convincing data on the impact of air pollution on the incidence of the population. The incidence of congenital malformations among newborns in Novokuznetsk and Kemerovo has increased, the incidence of lung cancer has increased in cities where aluminum plants and ferrous metallurgy enterprises are located. The resorts of the Black Sea and Caspian coasts of the Caucasus have become an environmental disaster zone.
Adapted from: Bondarev V.P., Dolgushin L.D., Zalogin B.S. "The ecological state of the territory of Russia", Moscow, 2004
L.F. Goldovskaya "Chemistry of the Environment", Moscow, 2007
Composition of the atmosphere. The atmosphere consists of a mixture of several gases called air, in which liquid and solid particles are suspended. The main gases of dry air are nitrogen (over 78% by volume) and oxygen (about 21%), a noticeable share belongs to argon (about 1%) and carbon dioxide (about 0.03%). In addition, the atmosphere contains trace amounts of krypton, xenon, neon, helium, hydrogen, ozone, iodine, radon, methane, ammonia, hydrogen peroxide, nitrous oxide and other gases. There is a variable amount of water vapor in the atmosphere, ranging from almost 0 to 4%.
Percentage of dry air constituents up to a height of about 100 km little changes. At altitudes from 10-20 to 50-60 kmwhen oxygen absorbs ultraviolet radiation from the sun, ozone is formed. Above 80 kmunder the influence of ultraviolet and corpuscular radiation from the Sun, charged oxygen and nitrogen atoms, charged nitrogen oxide molecules and free electrons prevail in the atmosphere. Above 1000 kmthe atmosphere is mostly helium, and above 2000 km - from hydrogen. The amount of water vapor greatly decreases with height. At a height of 5 kmits amount is 10 times less than that of the earth's surface, and at an altitude of 8 km- 100 times less.
The primary atmosphere of the Earth consisted mainly of water vapor, hydrogen and ammonia. Under the influence of ultraviolet radiation from the Sun, water vapor decomposed into hydrogen and oxygen. Hydrogen largely escaped into outer space, oxygen reacted with sammonia, and nitrogen and water were formed. At the early stage of the geological history of the Earth, carbon dioxide predominated in the atmosphere, which came from the depths during intense volcanic eruptions. With the appearance of green plants at the end of the Paleozoic, oxygen began to enter the atmosphere as a result of the decomposition of carbon dioxide during photosynthesis, and the composition of the atmosphere took on a modern form.
Particles suspended in the atmosphere are called aerosols.These include water droplets and crystals, dust of mineral and organic origin, smoke and ash from forest fires, combustion of fuels and volcanic eruptions, particles of sea salt, microorganisms, cosmic dust and radioactive decay products arising from test explosions of atomic and thermonuclear bombs. Aerosols are found mainly in the lowest layers of the atmosphere. Many of them serve as nuclei, on which condensation of water vapor begins during the formation of clouds and fog.
The physical state of the atmosphere. Let us consider the main characteristics of the physical state of the atmosphere, on which its structure and role in the development of the geographic envelope primarily depends. These characteristics include air temperature, pressure and density and the resulting air movement.
Pressure, density and temperature are related by the equation of state of gases
where R- pressure, ρ - density, T- temperature on an absolute scale, R - gas constant, depending on the nature of the gas. With sufficient approximation, this equation is applicable to the atmosphere. From the equation it follows that density and temperature are proportional to pressure. Therefore, if the pressure decreases with height, then the density and temperature should decrease.
The average annual air temperature at the earth's surface is 14 °. It varies widely: its extreme values \u200b\u200bare from + 58 ° (in tropical deserts) to -88 ° (in Antarctica). Temperature, as a rule, decreases according to a complex law with height.
The pressure exerted by the atmosphere on the earth's surface is, on average, 1013 mb.The highest pressure reduced to sea level was recorded in Asia (1080 mb), the lowest in the Pacific Ocean (887 mb).With height, the pressure decreases approximately exponentially, when the height increases in arithmetic progression. At level 5 kmpressure is almost half that at sea level, at 10 km- 4 times, at level 20 km- 18 times lower.
Air density decreases with altitude less than pressure. At the surface of the earth, the density is on average 1250 g / l 3, at a height of 5 km- 735 g / m 3,10 km- 411 g / m 3,20 km- 87 g / m 3.
Due to pressure changes, air constantly moves in horizontal and vertical directions, which leads to an exchange of heat and moisture on the earth's surface and in the lower atmosphere. Horizontal air movement occurs at an average speed at the earth's surface of 5-10 m / sec,maximum more than 50 m / sec.In the high layers of the atmosphere, speeds of 100 m / secand more. Vertical air movement occurs at a speed of several meters to 10-20 m / sec.
The structure of the atmosphere. In the vertical direction, the atmosphere can be imagined as consisting of several concentric layers, comparatively sharply differing in their physical properties. The pressure and density of the atmosphere decrease gradually with height and cannot be the cause of a jump-like change in the properties of the atmosphere. The change in temperature associated with pressure and density by the equation of state of gases decreases gradually only to a certain height. Further, ultraviolet and corpuscular
radiation from the Sun, where pressure and density are already small. Ultraviolet radiation leads to the formation ozone layer,in connection with which the decrease in temperature with altitude is first balanced, and then the temperature rises. At altitudes where the influence of ozone ceases to affect, the temperature begins to decrease again. At altitudes over 80 kmunder the influence of ultraviolet and corpuscular radiation of the Sun, ions are formed in the atmosphere, which again leads to an increase in temperature (Fig. 10). Thus, the main reason for the concentric structure of the atmosphere is the ultraviolet and corpuscular radiation of the Sun.
Lower atmosphere up to 17 kmover the equator and 8 kmabove the poles is called troposphere.The temperature in the troposphere decreases with altitude by an average of 0 °, 6 for every 100 m.In the troposphere, there is a continuous mixing of air, clouds are formed, precipitation falls. It contains up to 4/5 of the entire mass of the atmosphere and almost all of the water vapor. The processes taking place in the troposphere directly affect the weather and climate. The lower tropospheric layer adjacent to the earth's surface is called surface layer. Here, temperature changes during the day and year are especially pronounced. Layer from the earth's surface to a height of about 1000 m called friction layer,in which the wind speed decreases and its direction changes. The friction layer has a great influence on the general circulation of the atmosphere. In the process of the latter, the troposphere is divided into separate air masses, which, for a more or less long time, retain their individual physical properties (temperature, humidity, dust content). The horizontal distribution of air masses is measured in thousands of kilometers.
Above the troposphere up to a height of about 55 kmlocated stratosphere.It emits a layer of ozone with its maximum concentration at an altitude of 25 to 30 km.The lower stratosphere has a more or less constant temperature of about -70 ° above the equator and from -45 to -65 ° above the North Pole. From a height of 25 kmthe temperature begins to rise and at the upper limit of the stratosphere reaches 10-30 °. The distribution of temperature in the stratosphere is the reason for the dominance of horizontal air transport, which leads, in particular, to the exchange of air masses between latitudes.
At heights of the order of 55 to 80 kmlocated mesosphere.Here, the temperature drops with an altitude of up to several tens of degrees at the upper boundary, and therefore vertical air movement prevails.
Above the mesosphere to an altitude of about 1200 kmlocated ionosphere (thermosphere). The temperature in it rises to 1000 ° with altitude, and possibly more. The physical properties of the ionosphere depend mainly on the Earth's magnetosphere, solar activity and their fluctuations. This leads, in particular, to the formation of permanent and temporary layers and clouds with an increased density of ionized gas. The strong variability of the properties of the ionosphere indirectly affects the state of the lower atmosphere, and, consequently, the weather and climate.
Above the ionosphere is located protosphere,consisting mainly of hydrogen ions (protons). It extends to the upper boundary of the magnetosphere.
\u003e Condition of atmospheric air
Atmospheric air is, simply put, street air. The Earth's atmosphere is the air envelope around our planet. This is a layered cake, even, more precisely, a layered cocktail of various gases with a thickness of about 10 thousand km. The bartender in this case is gravity, which keeps heavier gases closer to the earth's crust, and lighter gases soar far on the periphery, and strive to escape completely into outer space.
The state of the atmospheric air at the moment is deplorable. The air that a person breathes is just a thin lower layer about 5 km in height: it is in it that we live, breathe, pollute it and fight for its purity.
Ambient air pollution is the number one problem in the world, atmospheric air pollutants roam over the entire earth's surface and are evenly distributed in the air column. At an altitude of 3-18 km, they are absorbed into the clouds, falling on the ground with acid rains. At an altitude of 40 km, the ozone layer is damaged - a natural shield from the destructive solar ultraviolet radiation. And up to 100 km, the atmosphere becomes less and less transparent, warming up the planet and creating the so-called "greenhouse effect", which is gradually changing the climate on all continents and, in the future, can melt polar ice and radically change the relief of the earth's surface.
The state of the atmospheric air is such that there is no special sense in trying to purify the air in one city or even a country, because the purified atmospheric air will fly away to travel, and the dirty air of the surrounding area will come in its place. It turns out that by polluting the air in our city, we harm, first of all, not ourselves, but our neighbors - near and far. And they are for us. This is called cross-border transport (ie "cross-border transport"). In the Russian Federation, a significant proportion of air pollutants are brought in by air from other countries.
There are also natural air pollutants. One volcanic eruption far surpasses the emissions of a powerful plant in its detrimental effect. And also the spring weathering of arable land, and sandstorms in deserts, and global processes of organic decay - in swamps, in landfills, in food shops. Every year, with the onset of hot weather, hectares of taiga and smaller forests begin to burn, and no state services can cope with this yet. As a result of all these processes, harmful substances enter the air. Moreover, volcanic dust and fumes from fires soar in those regions where there are no volcanoes or forests, and there are no close ones.
In Russia, the Federal Law "On the Protection of Atmospheric Air", the Law "On Environmental Protection" and "On the Radiation Safety of the Population", as well as a number of more special documents, are responsible for the state of atmospheric air. All of them establish standards for the environmental load on the air, prescribe the necessary actions to prevent abuse and sanctions for violations. However, as is often the case in Russia, the laws have been written, but no one observes them. The owners of chemical plants do not care about the fact that a huge number of citizens in our country breathe air polluted above any established limits. Effective cleaning equipment that could deal with huge amounts of harmful emissions is a separate item of expenditure, so it is easier for manufacturers to save money than to ensure the environmental safety of their economic facility.
By the way, many processes occurring with the "home" air are similar to atmospheric ones. Heated by batteries and radiators, the air rises in currents, the colder air is drawn in its place, and thus it is constantly mixed. We can say that every room, office, study has its own atmosphere, it is not for nothing that they say about a pleasant place: "there is a special atmosphere here."
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INTRODUCTION 2
1. General characteristics of the atmosphere and its pollution 3
2. Features of climate change 5
3. Carbon dioxide and the greenhouse effect 7
CONCLUSION 11
LIST OF REFERENCES 12
INTRODUCTION
“The state of the atmosphere. Causes of air pollution. Carbon dioxide and the greenhouse effect, climate change ”is one of the most important and urgent topics in ecology today.
The topic is relevant because at the turn of the XXI century. humanity faced a paradoxical fact: on the one hand, scientific and technological progress combined with environmental illiteracy caused environmental degradation; on the other hand, only man should become the guarantor of nature protection. Now, when man, according to V. I. Vernadsky's definition, has turned into a "huge geological force", we must protect the environment from man and for man, which is only part of the problems solved by ecology.
The aim of the work is to consider the state of the atmosphere, the causes of atmospheric pollution, as well as the features of carbon dioxide and the greenhouse effect and their impact on the atmosphere.
Main goals:
Examine the literature on the research problem.
Based on the theoretical analysis of the study of the problem, systematize knowledge about the state of the atmosphere and the reasons for its pollution.
Consider the nature and specifics of climate change, the features of carbon dioxide and the greenhouse effect.
To systematize and generalize the scientific approaches to this problem existing in the special literature.
For the disclosure of the topic, the following structure is defined: the work consists of an introduction, a main part and a conclusion. The titles of the main body reflect its content.
1. General characteristics of the atmosphere and its pollution
Air pollution is one of the main environmental problems. Air is one of the main natural resources. The atmosphere is the defining condition for life on the planet. It is known that a person can live without food - 5 months, without water - 5 days, and without air - less than 5 minutes. The quality of the atmosphere determines the life and health of people, the existence of flora and fauna. The air basin is most susceptible to pollution.
It is concentrated in a layer 5.5 km thick. the mass of the entire atmosphere, and in the 40 km layer - 99% of the entire mass of the atmosphere.
The lower part of the atmosphere (approximately 15 km) is the troposphere. Intense turbulent mixing is observed in it, winds blow and, thus, the temperature sharply decreases with height (by 1 km approximately 6 ° C). At an altitude of about 55 km, it is minimal - 3 ° С, and then there is an intense increase in temperature.
The composition of the air is mainly: N2 - 79%, O2 - 20 ... 21%, and a small amount of CO2, inert gases, hydrogen. Wed m.m. - 29 g / mol.
Air pollution is one of the most important environmental problems in most countries. A city with a population of 1 million people annually emits 10 million tons of water vapor, 2 million tons of gases (SO2, CO2, NO2, etc.) into the atmosphere. Approximately 20 thousand tons of dust and 150 tons of heavy metals (Pb, Zn, Cd, etc.) 1.
According to the World Health Organization (WHO), in the 1990s, in 27 out of 54 surveyed countries, the SO2 concentration exceeded the standard norms (40 - 60 μg / dm3). The list of cities with high air pollution is opened by Milan, then Tehran, Seoul, Rio de Janeiro, Paris, Beijing, Madrid.
The main indicator characterizing the state of the atmosphere is the concentration of harmful substances and its ratio with the MPC or the standards for maximum permissible emissions (MPE).
MPE are determined on the basis of MPC taking into account the dispersion of emissions and their superposition on background pollution.
The cumulative impact of several pollution sources is also taken into account. For combustion products (CO2, SO2, etc.), the MPE is calculated according to formula 2:
where MPC is the maximum permissible concentration; FROMf - background concentration of the emitted substance equal to zero; H- pipe height, m; V- volume of emissions, m3 / s; Δ T- excess of the emission temperature over the air temperature; N- the number of pollution sources; AND- the dimensionless coefficient, which determines the conditions for dispersion of impurities in the atmosphere, for the RF is equal to 120 FIs a dimensionless coefficient taking into account the sedimentation rate of impurities (for gases F= 5); m, n- dimensionless coefficients taking into account the conditions for the release of gases from emission sources: m≅ 0,4; n= 1 … 3.
Very often, the plant's emissions are higher than the MPE and it cannot reduce them under any circumstances (the Baikalsk Pulp and Paper Mill, which is still operating, is a dioxin source).
For such enterprises, the standards of temporarily agreed emissions (TME), calculated for a long-term emission reduction program, have been established.
Acidification of rains, and then soil and natural waters, at first proceeded as a hidden, imperceptible process. Clean, but already acidified lakes retained their deceptive beauty. The forest looked the same as before, but irreversible changes had already begun.
With acid rain, fir, spruce, pine most often suffer, because the needles change less often than the leaves change, and it accumulates more harmful substances in the same period of time. In coniferous trees, the needles turn yellow and fall off, the crowns are thinned, thin roots are damaged. In deciduous trees, the color of the leaves changes, the foliage falls off prematurely, part of the crown dies, and the bark is damaged. There is no natural regeneration of coniferous and deciduous forests. These symptoms are often accompanied by secondary damage from insects and tree diseases. The defeat of trees is increasingly affecting young forests.
The impact of sulfur dioxide and its derivatives on humans and animals is manifested primarily in the defeat of the upper respiratory tract. Under the influence of sulfur dioxide and sulfuric acid, the destruction of chlorophyll in plant leaves occurs, in connection with which photosynthesis and respiration deteriorate, growth slows down, the quality of tree plantations and crop yields decrease, and at higher and prolonged exposure doses, the vegetation dies.
The so-called "acidic" rains cause an increase in soil acidity, which reduces the effectiveness of the applied mineral fertilizers on arable land, and leads to the loss of the most valuable part of the species composition on long-term cultivated hayfields and pastures. Sod-podzolic and peat soils, which are widespread in northern Europe, are especially susceptible to the influence of acidic precipitation.
To reduce material damage, metals sensitive to automobile emissions are replaced with aluminum; special gas-resistant solutions and paints are applied to structures. Many scientists see the development of motor transport and the increasing air pollution in large cities by automobile gases as the main reason for the increase in lung disease.
The ozone layer is located in the upper atmosphere (stratosphere) and contains large amounts of ozone (O3). It begins at an altitude of about 8 km above the poles and 17 km above the equator. Its purpose is to absorb shortwave ultraviolet radiation. In 1985, atmospheric researchers from the British Antarctic Survey reported a completely unexpected fact: the spring ozone content in the atmosphere over Halley Bay station in Antarctica decreased by 40% between 1977 and 1984. Soon this conclusion was confirmed by other researchers, who also showed that the area of \u200b\u200blow ozone content extends beyond Antarctica and covers a layer from 12 to 24 km in height, i.e. much of the lower stratosphere.
Ultraviolet light destroys normally stable CFC molecules, which break down into highly reactive components, in particular atomic chlorine. Thus, CFCs carry chlorine from the Earth's surface through the troposphere and the lower atmosphere, where less inert chlorine compounds are destroyed, into the stratosphere, to the layer with the highest ozone concentration. It is very important that chlorine acts like a catalyst in the destruction of ozone: during the chemical process, its amount does not decrease.
2. Features of climate change
Climate change is caused by changes in the earth's atmosphere, processes occurring in other parts of the Earth, such as oceans, glaciers, as well as the effects associated with human activities. External processes that shape the climate are changes in solar radiation and the Earth's orbit 3.
changes in the size and relative position of continents and oceans,
change in the luminosity of the sun,
changes in the parameters of the Earth's orbit,
changes in the transparency of the atmosphere and its composition as a result of changes in volcanic
earth activity,
change in the concentration of CO2 in the atmosphere when interacting with the biosphere,
change in the reflectivity of the Earth's surface (albedo),
change in the amount of heat available in the depths of the ocean.
Consider the main climatic changes on Earth.
Weather is the daily state of the atmosphere. Weather is a chaotic, nonlinear dynamic system. Climate is an average weather condition and, on the contrary, is stable and predictable. Climate includes indicators such as average temperature, rainfall, number of sunny days and other variables that can be measured at a specific location. However, such processes are taking place on Earth that can affect the climate.
Glaciers are recognized as one of the most sensitive indicators of climate change. They significantly increase in size during the cooling of the climate (the so-called "small ice ages") and decrease during the warming of the climate. Glaciers grow and melt due to natural changes and external influences. In the past century, glaciers have not been able to regenerate enough ice during the winters to recover ice loss during the summer months. The most significant climatic processes over the past several million years are the glacial and interglacial cycles of the current ice age, driven by changes in the Earth's orbit. Changing continental ice conditions and sea level fluctuations within 130 meters are key consequences of climate change in most regions.
On the scale of decades, climate change can result from the interaction of the atmosphere and the world's oceans. Many climate fluctuations, including the most famous El Niño Southern Oscillation, and the North Atlantic and Arctic Oscillations, are due in part to the world's oceans' ability to accumulate thermal energy and the movement of this energy to different parts of the ocean. On a longer scale, thermohaline circulation occurs in the oceans, which plays a key role in the redistribution of heat and can significantly affect the climate.
In a more general aspect, the variability of the climate system is a form of hysteresis, that is, it means that the current state of the climate is not only a consequence of the influence of certain factors, but also the entire history of its state. For example, in ten years of drought, lakes partially dry up, plants die, and the area of \u200b\u200bdeserts increases. These conditions, in turn, cause less abundant rainfall in the years following the drought. T. about. climate change is a self-regulating process, since the environment reacts in a certain way to external influences, and, changing, is itself capable of influencing the climate.
Cattle are responsible for 18% of the world's greenhouse gas emissions, according to the 2006 UN Long Shadow of Livestock Report. This includes changes in land use, ie deforestation for pasture purposes. In the Amazon rainforest, 70% of deforestation is for grazing, which is the main reason why the Food and Agriculture Organization (FAO) included land use in the livestock sector in its 2006 agricultural report. In addition to CO2 emissions, livestock production is responsible for 65% of nitrogen oxide and 37% of methane emissions, both of which are anthropogenic.
3. Carbon dioxide and the greenhouse effect
Systematic observations of the content of carbon dioxide in the atmosphere show its growth. It is known that CO2 in the atmosphere, like glass in a greenhouse, transmits the radiant energy of the Sun to the surface of the Earth, it delays the infrared (thermal) radiation of the Earth and thereby creates the so-called greenhouse (greenhouse) effect.
Volcanoes are also part of the carbon geochemical cycle. Over many geological periods, carbon dioxide has been released from the Earth's interior into the atmosphere, thereby neutralizing the amount of CO2 removed from the atmosphere and bound by sedimentary rocks and other geological sinks of CO2. However, this contribution does not compare in magnitude with anthropogenic carbon monoxide emissions, which, according to the US Geological Survey, are 130 times the amount of CO2 emitted by volcanoes 4.
Anthropogenic factors include human activities that change the environment and affect the climate. In some cases, the causal relationship is direct and unambiguous, such as the effect of irrigation on temperature and humidity, in other cases the relationship is less obvious. Various hypotheses of human influence on climate have been discussed over the years. At the end of the 19th century, for example, the rain follows the plow theory was popular in the western United States and Australia.
The main problems today are the increasing concentration of CO2 in the atmosphere due to fuel combustion, aerosols in the atmosphere that affect its cooling, and the cement industry. Other factors such as land use, ozone depletion, animal husbandry and deforestation also affect the climate.
Starting to grow during the industrial revolution in the 1850s and gradually accelerating, human consumption of fuel has caused the concentration of CO2 in the atmosphere to increase from ~ 280 ppm to 380 ppm. With this growth, the projected concentration at the end of the 21st century will be more than 560 ppm. It is known that the level of CO2 in the atmosphere is now higher than at any time in the last 750,000 years. Together with increasing methane concentrations, these changes herald a 1.4-5.6 ° C rise in temperature between 1990 and 2100.
Anthropogenic aerosols, especially sulphates emitted from fuel combustion, are believed to influence the cooling of the atmosphere. It is believed that this property is responsible for the relative "plateau" in the temperature graph in the middle of the 20th century.
Cement production is an intense source of CO2 emissions. Carbon dioxide is formed when calcium carbonate (CaCO3) is heated to produce calcium oxide (CaO or quicklime) as an ingredient in cement. Cement production is responsible for approximately 2.5% of CO2 emissions from industrial processes (energy and industrial sectors).
Global climate change is closely related to air pollution from industrial waste and exhaust gases. The impact of human civilization on the Earth's climate is a reality, the consequences of which are already being felt. Scientists believe that the intense heat in 1988 and the drought in the United States are to some extent a consequence of the so-called effect - global warming of the earth's atmosphere as a result of an increase in carbon dioxide content in it due to deforestation that absorbs it fuels like coal and gasoline, which release this gas into the atmosphere. Carbon dioxide and other pollutants act like film or glass in greenhouses: they let the sun's heat into the Earth and keep it there. In general, the temperature on the ground in the first 5 months. 1988 was higher than any comparable period in 130 years of measurement. It can be argued that the long-anticipated global warming associated with environmental pollution was the cause of the temperature change. The warming trend is not a natural phenomenon, but a consequence of the greenhouse effect.
The 1980s, the scientists pointed out, were the four warmest years of the last century, and 1988 broke all previous records. Computer forecasts promise further warming in the 90s. and in the new millennium.
As you know, the main “greenhouse” gas is water vapor. It is followed by carbon dioxide, providing in the 80s. 49% additional increase in the greenhouse effect compared to the beginning of the last century, methane (18%), freons (14%), nitrous oxide N2O (6%). The rest of the gases account for 13%.
Scientists associate climate change with changes in the content of greenhouse gases in the atmosphere. It is known 550 how the chemical composition of the atmosphere changed for 160 thousand years. This information was obtained on the basis of analysis of the composition of air bubbles in glacial cores extracted from a depth of up to 2 km at the Vostok station in Antarctica and Greenland. It was found that during warm periods, the concentrations of CO 2 and CH 4 were about 1.5 times higher than in cold glacial periods. These results confirm the assumption made in 1861 by J. Tyndall that the history of changes in the Earth's climate can be explained by changes in the concentration of СО 2 in the atmosphere.
The greenhouse effect will disrupt the planet's climate by altering critical variables such as precipitation, wind, cloud cover, ocean currents and the size of the polar ice caps. While the implications for individual countries are far from clear, scientists are confident in the general trends. The interior regions of the continents will become drier and the coasts wetter. The cold seasons will become shorter and the warm ones longer. Increased evaporation will cause the soil to become drier over large areas 5.
One of the most widely discussed and feared consequences of the greenhouse effect is the projected rise in sea level as a result of rising temperatures. Most scientists believe that this rise will be relatively gradual, creating problems mainly in countries with large populations living at or below sea level, such as the Netherlands and Bangladesh. In terms of geographic areas, the greenhouse effect may be greatest in the high latitudes of the northern hemisphere. Snow and ice reflect sunlight into outer space, preventing temperatures from rising. But with warming around the globe, floating Arctic ice will begin to melt, leaving less snow and ice for reflection.
CONCLUSION
Summing up the work, the following conclusions can be drawn:
The atmosphere is the lightest shell of the Earth, which borders on outer space; the exchange of matter and energy with space is carried out through the atmosphere. The composition of the atmosphere mainly includes: N2 (78%); O2 (21%); CO2 (0.03%). The main indicator characterizing the state of the atmosphere is the concentration of harmful substances and its ratio with the MPC or the standards for maximum permissible emissions (MPE). MPE are determined on the basis of MPC taking into account the dispersion of emissions and their superposition on background pollution.
Climate change - fluctuations in the climate of the Earth as a whole or its individual regions over time. It is studied by the science of paleoclimatology. Climate change is caused by dynamic processes on Earth, external influences such as fluctuations in the intensity of solar radiation, and, more recently, human activities. Recently, the term "climate change" has been used as a rule (especially in the context of environmental policy) to refer to changes in the modern climate.
Climate change is caused by changes in the earth's atmosphere, processes occurring in other parts of the Earth, such as oceans, glaciers, as well as the effects associated with human activities.
Systematic observations of the content of carbon dioxide in the atmosphere show its growth. It is known that CO2 in the atmosphere, like glass in a greenhouse, transmits the radiant energy of the Sun to the surface of the Earth, it delays the infrared (thermal) radiation of the Earth and thereby creates the so-called greenhouse (greenhouse) effect. One of the most widely discussed and feared consequences of the greenhouse effect is the projected rise in sea level as a result of rising temperatures.
LIST OF USED LITERATURE
Valova (Kopylova) V.D. Ecology: textbook. - M .: Publishing house Dashkov and K. 2007
V.I. Korobkin, L.V. Peredelsky Ecology: a textbook for universities. - M. 2005 - 576 p.
Surface conditions atmosphere unacceptable and dangerous. Anthropogenic processes pollution air basin in most .... This is due to many reasons, and, above all, dysfunctional condition air basin of megalopolises, ...
