The increase in temperature in the troposphere of the atmosphere with increasing altitude is characterized as temperature inversion(Fig. 11.1, c). In this case, the atmosphere turns out to be very stable. The presence of inversion significantly slows down the vertical movement of pollutants and, as a result, increases their concentration in the ground layer.
The most commonly observed inversion occurs when a layer of air descends into an air mass with more high pressure, or during radiative heat loss by the earth's surface at night. The first type of inversion is usually called subsidence inversion. The inversion layer in this case is usually located at some distance from earth's surface, and an inversion is formed by adiabatic compression and heating of the air layer as it descends down into the region of the high pressure center.
From equation (11.5) we obtain:
Specific isobaric heat capacity value WITH p for air does not vary significantly with temperature over a fairly large temperature range. However, due to changes in barometric pressure, the density at the upper boundary of the inversion layer is less than at its base, i.e.
. (11.11)
This means that the upper boundary of the layer heats up faster than the lower boundary. If the subsidence continues for a long time, a positive temperature gradient will be created in the layer. Thus, the descending air mass is like a giant lid for the atmosphere located below the inversion layer.
Subsidence inversion layers are usually above emission sources and thus do not have a significant impact on short-term pollution events atmospheric air. However, such an inversion can last for several days, which affects the long-term accumulation of pollutants. Pollution events with hazardous health consequences observed in urban areas in the past have often been associated with subsidence inversions.
Let's consider the reasons leading to the occurrence radiation inversion. In this case, the layers of the atmosphere located above the Earth's surface receive heat during the day due to thermal conductivity, convection and radiation from the Earth's surface and eventually warm up. As a result, the temperature profile of the lower atmosphere is usually characterized by a negative temperature gradient. If a clear night follows, the earth's surface radiates heat and cools quickly. The layers of air adjacent to the earth's surface are cooled to the temperature of the layers located above. As a result, the daily temperature profile is transformed into a profile of the opposite sign, and the layers of the atmosphere adjacent to the earth's surface are covered with a stable inversion layer. This type of inversion occurs in the early hours and is typical during periods of clear skies and calm weather. The inversion layer is destroyed by rising currents of warm air that arise when the earth's surface is heated by the rays of the morning sun.
Radiative inversion plays an important role in atmospheric pollution, since in this case the inversion layer is located inside the layer that contains the pollution sources (unlike subsidence inversion). In addition, radiation inversion most often occurs under conditions of cloudless and windless nights, when there is little likelihood of air purification from precipitation or crosswinds.
The intensity and duration of the inversion depends on the season. In autumn and winter, as a rule, long inversions take place, their number is large. Inversions are also influenced by the topography of the area. For example, cold air, accumulated at night in the intermountain basin, can be “locked” there by the warm air that appears above it.
Other types of local inversions are also possible, such as those associated with sea breezes as a warm air front passes over a large continental landmass. The passage of a cold front preceded by an area of warm air also leads to an inversion.
Inversions are common in many areas. For example, on the west coast of the United States they are observed for almost 340 days a year.
The degree of stability of the atmosphere can be determined by the magnitude of the “potential” temperature gradient:
. (11.12)
Where 
– temperature gradient observed in the surrounding air.
Negative value of the “potential” temperature gradient ( G sweat< 0) свидетельствует о сверхадиабатическом характере профиля температуры и неустойчивых условиях в атмосфере. В случае, когдаG sweat > 0, the atmosphere is stable. If the “potential” temperature gradient approaches zero ( G sweat 0), the atmosphere is characterized as indifferent.
In addition to the considered cases of temperature inversion, which are local in nature, two inversion zones of a global nature are observed in the Earth’s atmosphere. The first zone of global inversion from the Earth's surface begins at the lower boundary of the tropopause (11 km for the standard atmosphere) and ends at the upper boundary of the stratopause (approximately 50 km). This inversion zone prevents the spread of impurities formed in the troposphere or released from the Earth's surface to other areas of the atmosphere. The second zone of global inversion, located in the thermosphere, to a certain extent prevents the dispersion of the atmosphere into outer space.
Let us consider, using an example, the procedure for determining the “potential” temperature gradient. The temperature at the Earth's surface at an altitude of 1.6 m is –10 °C, at an altitude of 1800 m – –50 °C, –12 °C, –22 °C.
The purpose of the calculation is to assess the state of the atmosphere based on the magnitude of the “potential” temperature gradient.
To calculate the “potential” temperature gradient, we use equation (11.12)
Here G= 0.00645 degrees/m – standard, or normal adiabatic vertical temperature gradient.
Let us analyze the calculated values of the “potential” temperature gradient. The nature of temperature changes for the considered cases of atmospheric conditions is presented in Fig. 11.2.
G sweat 1< 0 свидетельствует о сверхадиабатическом характере профиля температуры и неустойчивых условиях в атмосфере.
G sweat 2 > 0 – the atmosphere is stable.
G sweat 3 ≈ 0 – the atmosphere is characterized as indifferent.
The increase in temperature in the troposphere of the atmosphere with increasing altitude is characterized as temperature inversion(Fig. 11.1, c). In this case, the atmosphere turns out to be very stable. The presence of inversion significantly slows down the vertical movement of pollutants and, as a result, increases their concentration in the ground layer.
The most commonly observed inversion occurs when a layer of air descends into an air mass with higher pressure, or during radiative heat loss from the earth's surface at night. The first type of inversion is usually called subsidence inversion. The inversion layer in this case is usually located at some distance from the earth's surface, and the inversion is formed by adiabatic compression and heating of the air layer as it descends down to the area of the high pressure center.
From equation (11.5) we obtain:
Specific isobaric heat capacity value WITH p for air does not vary significantly with temperature over a fairly large temperature range. However, due to changes in barometric pressure, the density at the upper boundary of the inversion layer is less than at its base, i.e.
. (11.11)
This means that the upper boundary of the layer heats up faster than the lower boundary. If the subsidence continues for a long time, a positive temperature gradient will be created in the layer. Thus, the descending air mass is like a giant lid for the atmosphere located below the inversion layer.
Subsidence inversion layers usually appear above emission sources and, thus, do not have a significant impact on short-term air pollution phenomena. However, such an inversion can last for several days, which affects the long-term accumulation of pollutants. Pollution events with hazardous health consequences observed in urban areas in the past have often been associated with subsidence inversions.
Let's consider the reasons leading to the occurrence radiation inversion. In this case, the layers of the atmosphere located above the Earth's surface receive heat during the day due to thermal conductivity, convection and radiation from the Earth's surface and eventually warm up. As a result, the temperature profile of the lower atmosphere is usually characterized by a negative temperature gradient. If a clear night follows, the earth's surface radiates heat and cools quickly. The layers of air adjacent to the earth's surface are cooled to the temperature of the layers located above. As a result, the daily temperature profile is transformed into a profile of the opposite sign, and the layers of the atmosphere adjacent to the earth's surface are covered with a stable inversion layer. This type of inversion occurs in the early hours and is typical during periods of clear skies and calm weather. The inversion layer is destroyed by rising currents of warm air that arise when the earth's surface is heated by the rays of the morning sun.
Radiative inversion plays an important role in atmospheric pollution, since in this case the inversion layer is located inside the layer that contains the pollution sources (unlike subsidence inversion). In addition, radiation inversion most often occurs under conditions of cloudless and windless nights, when there is little likelihood of air purification from precipitation or crosswinds.
The intensity and duration of the inversion depends on the season. In autumn and winter, as a rule, long inversions take place, their number is large. Inversions are also influenced by the topography of the area. For example, cold air that accumulates in an intermountain basin at night can be “locked” there by warm air that appears above it.
Other types of local inversions are also possible, such as those associated with sea breezes as a warm air front passes over a large continental landmass. The passage of a cold front preceded by an area of warm air also leads to an inversion.
Inversions are common in many areas. For example, on the west coast of the United States they are observed for almost 340 days a year.
The degree of stability of the atmosphere can be determined by the magnitude of the “potential” temperature gradient:
. (11.12)
Where 
– temperature gradient observed in the surrounding air.
Negative value of the “potential” temperature gradient ( G sweat< 0) свидетельствует о сверхадиабатическом характере профиля температуры и неустойчивых условиях в атмосфере. В случае, когдаG sweat > 0, the atmosphere is stable. If the “potential” temperature gradient approaches zero ( G sweat 0), the atmosphere is characterized as indifferent.
In addition to the considered cases of temperature inversion, which are local in nature, two inversion zones of a global nature are observed in the Earth’s atmosphere. The first zone of global inversion from the Earth's surface begins at the lower boundary of the tropopause (11 km for the standard atmosphere) and ends at the upper boundary of the stratopause (approximately 50 km). This inversion zone prevents the spread of impurities formed in the troposphere or released from the Earth's surface to other areas of the atmosphere. The second zone of global inversion, located in the thermosphere, to a certain extent prevents the dispersion of the atmosphere into outer space.
Let us consider, using an example, the procedure for determining the “potential” temperature gradient. The temperature at the Earth's surface at an altitude of 1.6 m is –10 °C, at an altitude of 1800 m – –50 °C, –12 °C, –22 °C.
The purpose of the calculation is to assess the state of the atmosphere based on the magnitude of the “potential” temperature gradient.
To calculate the “potential” temperature gradient, we use equation (11.12)
Here G= 0.00645 degrees/m – standard, or normal adiabatic vertical temperature gradient.
Let us analyze the calculated values of the “potential” temperature gradient. The nature of temperature changes for the considered cases of atmospheric conditions is presented in Fig. 11.2.
G sweat 1< 0 свидетельствует о сверхадиабатическом характере профиля температуры и неустойчивых условиях в атмосфере.
G sweat 2 > 0 – the atmosphere is stable.
G sweat 3 ≈ 0 – the atmosphere is characterized as indifferent.
The temperature gradient of the atmosphere can vary widely. On average, it is 0.6°/100 m. But in a tropical desert near the surface of the earth it can reach 20°/100 m. With temperature inversion, the temperature increases with height and the temperature gradient becomes negative, i.e. it can be equal to, for example , -0.6°/100 m. If the air temperature is the same at all altitudes, then the temperature gradient is zero. In this case, the atmosphere is said to be isothermal.[...]
Temperature inversions determine the reverse arrangement of vertical soil zones in many mountain systems of continental regions. So, in Eastern Siberia At the foot and in the lower parts of the slopes of some mountains there are inversion tundras, then there are mountain taiga forests and higher again mountain tundras. Inversion tundras cool only in certain seasons, and during the rest of the year they are much warmer than the “upper” tundras and are used in agriculture.[...]
Temperature inversion manifests itself in an increase in air temperature with height in a certain layer of the atmosphere (usually in the range of 300-400 m from the Earth's surface) instead of the usual decrease. As a result, the circulation of atmospheric air is sharply disrupted, smoke and pollutants cannot rise upward and do not dissipate. Fogs often occur. Concentrations of sulfur oxides, suspended dust, and carbon monoxide reach levels dangerous to human health, leading to circulatory and respiratory disorders, and often to death. In 1952, in London, more than four thousand people died from smog from December 3 to December 9, and up to ten thousand people became seriously ill. At the end of 1962, in the Ruhr (Germany), smog killed 156 people in three days. Only the wind can dispel smog, and reducing the emissions of pollutants can smooth out a smog-dangerous situation.[...]
Temperature inversions are associated with cases of mass poisoning of the population during periods of toxic fogs (the Manet River valley in Belgium, more than once in London, Los Angeles, etc.).[...]
Sometimes temperature inversions spread over large areas of the earth's surface. The area of their distribution usually coincides with the area of distribution of anticyclones, which arise in zones of high barometric (Pressure.[...]
Synonym: temperature inversion. FRICTION INVERSION. See turbulent inversion.[...]
Under the influence of cold winters and temperature inversions, soils freeze deeply in winter and slowly warm up in spring. For this reason, microbiological processes are weak, and despite the high humus content in the soil, it is necessary to add higher standards organic fertilizers (manure, peat and composts) and mineral fertilizers readily available to plants.[...]
Two other types of local inversions are possible. One of them is related to the sea breeze mentioned above. Warming of the morning air over land causes cooler air to flow landward from the ocean or large enough lake. As a result, more warm air rises up, and the cold one takes its place, creating inversion conditions. Inversion conditions are also created when a warm front passes over a large continental land area. A warm front often tends to "crush" denser, cooler air ahead of it, thereby creating a local temperature inversion. The passage of a cold front, in front of which there is an area of warm air, leads to the same situation.[...]
Temperature inversion associated with vertical air movements can lead to the same consequences.[...]
The fan-shaped shape of the strings occurs during a temperature inversion. Its shape resembles a meandering river, which gradually widens with distance from the pipe.[...]
In the small American city of Donora, such a temperature inversion caused illness in about 6,000 people (42.7% of the total population), with some (10%) showing symptoms indicating the need for hospitalization of these people. Sometimes the consequences of a long-term temperature inversion can be compared to an epidemic: in London, 4,000 people died during one of these long-term inversions.[...]
A fan-shaped jet (Fig. 3.2, c, d) is formed during temperature inversion or with a temperature gradient close to isothermal, which characterizes very weak vertical mixing. The formation of a fan-shaped jet is favored by weak winds, clear skies and snow cover. This jet is most often observed at night.[...]
In unfavorable weather situations such as temperature inversion, high air humidity and precipitation, the accumulation of pollution can occur particularly intensively. Typically, in the surface layer, the air temperature decreases with height, and vertical mixing of the atmosphere occurs, reducing the concentration of pollution in the surface layer. However, under certain meteorological conditions (for example, during intense cooling of the earth's surface at night), a so-called temperature inversion occurs, i.e., the temperature in the surface layer changes to the opposite direction; with increasing altitude, the temperature increases. Typically, this condition lasts a short time, but in some cases, a temperature inversion can be observed for several days. During a temperature inversion, the air near the earth's surface appears to be enclosed in a limited volume, and very high concentrations of pollution can occur near the earth's surface, contributing to increased contamination of insulators.[...]
Burnazyan A.I. et al. Pollution of the surface layer of the atmosphere during temperature inversions.[...]
DUST HORIZON. The upper boundary of the dust (or smoke) layer underlying the temperature inversion. When observed from a height, the impression of a horizon is created.[...]
Under some unfavorable meteorological conditions (low wind, temperature inversion), the release harmful substances into the atmosphere leads to mass poisoning. An example of mass poisoning of the population are the disasters in the Meuse River valley (Belgium, 1930), in the city of Donora (Pennsylvania, USA, 1948). In London, mass poisoning of the population during catastrophic air pollution was observed repeatedly - in 1948, 1952, 1956, 1957, 1962; As a result of these events, several thousand people died, many were seriously poisoned.[...]
In areas with anticyclonic weather and in the presence of significant inversions, the maximum accumulation of impurities is observed in valleys and basins in the zone of “cold lakes,” i.e., at a level of 200-300 m from their bottom, therefore, when forming the functional-planning structure of a city settlement, it is necessary In addition to the wind rose, take into account the rose of temperature inversions and their duration. Zone settlement they are located on the slopes above the “cold lakes”, and the industrial zone is located lower in relief in relation to the residential area; streets and open retail spaces are oriented in the direction of prevailing winds to enhance ventilation. When forming an industrial zone at the foot of hills and mountains, planning methods are used to organize the passage of cold air masses flowing into depressions, using protective zones, streets, driveways, etc.[...]
In the depressions of cities (for example, Los Angeles, Kemerovo, Alma-Ata, Yerevan), a temperature inversion is observed, as a result of which natural mixing of air masses does not occur, and harmful substances accumulate in it. The problem of photochemical smog also exists in other major cities where sunny weather prevails (Tokyo, Sydney, Mexico City, Buenos Aires, etc.).[...]
Old-timers of New York know well what poisonous air is. In 1935, more than 200 people died in a few days of temperature inversion, in 1963 - more than 400, and in 1966 - about 200 people.[...]
Los Angeles (summer, photochemical) smog occurs in the summer also in the absence of wind and temperature inversion, but always in sunny weather. It is formed when solar radiation affects nitrogen oxides and hydrocarbons entering the air as part of vehicle exhaust gases and industrial emissions. As a result, highly toxic pollutants are formed - photooxidants, consisting of ozone, organic peroxides, hydrogen peroxide, aldehydes, etc. [...]
Products of incomplete combustion of fuel, which react with airborne fog during periods of temperature inversion, are the cause of the formation of smog, which has claimed many lives in the past.[...]
The acute effect of atmospheric pollution is provoked abrupt change weather conditions in the given territory (temperature inversion, calm, fog, strong steady wind from the industrial zone), as well as accidents at industrial enterprises of the city or at wastewater treatment plants, as a result of which the concentration of pollution in the atmospheric air of residential areas increases significantly, often exceeding permissible levels by tens of times. A particularly difficult situation arises in cases where both of these events occur simultaneously.[...]
In a number of cities, atmospheric emissions are so significant that in weather unfavorable for self-purification of the atmosphere (calm air, temperature inversion, in which smoke spreads to the ground, anticyclonic weather with fog), the concentration of pollutants in the surface air reaches a critical value, at which an acutely expressed reaction of the body to harmful atmospheric emissions. In this case, two situations are distinguished (dense fog mixed with smoke) of the London type and photochemical fog (Los Angeles). [...]
London type; smog occurs in winter in large industrial cities under unfavorable weather conditions (lack of wind and temperature inversion).[...]
London (winter) smog is formed in winter in large industrial centers under unfavorable weather conditions: lack of wind and temperature inversion. Temperature inversion manifests itself in an increase in air temperature with height (in a layer of 300-400 m) instead of the usual decrease.[...]
Atmospheric air pollution negatively affects public health and sanitary living conditions. When there is no wind, fog and temperature inversions, when dispersion of emissions becomes difficult, the concentration of impurities in the air increases, especially sulfur dioxide and photooxidants, which has an acute effect on people, causing lacrimation, conjunctivitis, cough, bronchitis, as well as exacerbation of diseases, chronic obstructive pulmonary diseases , cardiovascular diseases.[...]
The accumulation of photochemical reaction products in the atmospheric air as a result of unfavorable meteorological conditions (lack of wind, temperature inversions) leads to a situation called photochemical smog, or Los Angeles-type smog. The main symptoms of such smog are irritation of the mucous membranes of the eyes and nasopharynx in humans, decreased visibility, characteristic bad smell, as well as the death of vegetation and damage to rubber products. At the same time, the oxidizing capacity of air significantly increases due to the presence of oxidizing agents in it, primarily ozone and some others.[...]
Areas with a predominance of weak winds or calm conditions are especially unfavorable for the dispersion of harmful substances in the air. Under these conditions, temperature inversions occur, during which there is an excessive accumulation of harmful substances in the atmosphere. An example of such an unfavorable location is Los Angeles, sandwiched between mountain range, which weakens the wind and prevents the outflow of polluted urban air, and Pacific Ocean. In this city, temperature inversions occur on average 270 times a year, and 60 of them are accompanied by very high concentrations of harmful substances in the air.[...]
Here, per capita, a much larger amount of petroleum products, including motor gasoline, is consumed per capita than anywhere else. At the same time, almost no coal is used. The air is polluted mainly by hydrocarbons and other products of petroleum combustion, as well as products from the burning of household and garden waste by private homeowners. Recently, measures have been taken to centralize the collection and disposal of household waste. Legislation prohibits the release into the atmosphere of smoke with a density of 2 or more units on the Ringelmann scale for more than 3 minutes per hour. Sulfur compounds may be released into the atmosphere in concentrations not exceeding 0.2% by volume. This emission limitation is not too stringent, since it fully allows the use of oil with a sulfur content of 3% in power plants. Regarding dust emissions, this county's ordinance provides: a scale that varies depending on the total amount of fuel consumed. The maximum emission should not exceed 18 kg per hour. Such a restriction would be impractical in many areas, but in Los Angeles County almost no coal is used and there are several plants that emit large amounts of dust into the atmosphere.[...]
The ability of the earth's surface to absorb or emit heat affects the vertical distribution of temperature in the surface layer of the atmosphere and leads to temperature inversion (deviation from adiabaticity). An increase in air temperature with altitude means that harmful emissions cannot rise above a certain ceiling. Under inversion conditions, turbulent exchange is weakened and conditions for the dispersion of harmful emissions in the surface layer of the atmosphere worsen. For the surface inversion, the repeatability of the heights of the upper boundary is of particular importance; for the elevated inversion, the repeatability of the lower boundary is of particular importance.[...]
In the Soviet Union, there was also a case of poisoning of the population of an industrial city with sulfur dioxide in winter as a result of the formation of a powerful layer of temperature inversion near the ground, which contributed to the pressing of a jet of flue gases to the ground. [...]
It is necessary to avoid the construction of enterprises with significant emissions of harmful substances on sites where long-term stagnation of impurities can occur when weak winds and temperature inversions are combined (for example, in deep basins, in areas of frequent fog formation, in particular in areas with severe winters below hydroelectric dams, as well as in areas where smog may occur).[...]
In some cases, the determination of gross production is carried out according to the daily curve of the CO2 level in the cenosis. In an oak-pine forest, for example, the air drops some nights as a result of a temperature inversion (temperature increases from the soil up into the canopy). In this case, CO2 released during breathing accumulates below the inversion layer and its amount can be measured. By summarizing the results of studying the distribution of CO2 depending on the environmental temperature in different seasons of the year, it is possible to obtain approximate estimates of the respiration rate of the entire community as a whole. Thus, the cost of respiration for the oak-pine community is 2110 g/m2-year. Measurements in a gas chamber show that plants directly spend 1450 g/m2-year on respiration. The difference between these two figures, equal to 660 g/m2-year, is the result of the respiration of animals and saprobes.[...]
The distribution of technogenic impurities depends on the power and location of the sources, the height of the pipes, the composition and temperature of the exhaust gases and, of course, on meteorological conditions. Calm, fog, and temperature inversion sharply slow down the dispersion of emissions and can cause excessive local air pollution and the formation of a gas-smoke “cap” over the city. This is how the catastrophic London smog arose at the end of 1951, when 3.5 thousand people died in two weeks from a sharp exacerbation of pulmonary and heart diseases and direct poisoning. Smog in the Ruhr region at the end of 1962 killed 156 people in three days. There are known cases of very serious smog phenomena in Mexico City, Los Angeles and many other large cities.[...]
Mountain valleys oriented along the direction of prevailing winds are characterized by increased average speed wind, especially with large horizontal atmospheric pressure gradients. Under such conditions, temperature inversions occur less frequently. In addition, if temperature inversions occur simultaneously with moderate and strong winds, then their influence on the scattering properties of the atmosphere is small. The conditions for the dispersion of impurities in valleys of this type are more favorable than in valleys where the wind lash is weaker than in flat conditions. [...]
Conditions conducive to the formation of photochemical fog at high levels of atmospheric air pollution with reactive organic compounds and nitrogen oxides are an abundance of solar radiation, temperature inversions and low wind speeds.[...]
A typical example of the acute provoking influence of atmospheric pollution are cases of toxic fogs that occurred in different times in cities of different continents of the world. Toxic fogs appear during periods of temperature inversions with low wind activity, i.e., in conditions conducive to the accumulation of industrial emissions in the surface layer of the atmosphere. During periods of toxic fog, an increase in pollution was recorded, the more significant the longer the conditions for air stagnation persisted (3-5 days). During periods of toxic fog, the mortality rate of people suffering from chronic cardiovascular and pulmonary diseases increased, and exacerbations of these diseases and the emergence of new cases were recorded among those who sought medical help. Flashes bronchial asthma described in a number of populated areas when specific pollution appears. It can be assumed that acute cases of allergic diseases will occur when air is polluted with biological products such as protein dust, yeast, mold and their waste products. An example of the acute effects of air pollution are cases of photochemical fog due to a combination of factors: vehicle emissions, high humidity, calm weather, intense ultraviolet radiation. Clinical manifestations: irritation of the mucous membranes of the eyes, nose, upper respiratory tract.[ ...]
Thus, nowhere on the territory of the USSR are such unfavorable meteorological conditions created for the transfer and dispersion of emissions from low emission sources as on the territory of the Baikal-Amur Mainline. Calculations show that due to the high frequency of stagnant conditions in a large layer of the atmosphere and powerful temperature inversions with the same emission parameters, the level of air pollution in the cities and towns of BAM can be 2-3 times higher than in the European territory of the country. In this regard, protecting the air basin from pollution of the newly developed territory adjacent to the BAM is especially important.[...]
Probably the most notorious smog area in the world is Los Angeles. There are plenty of chimneys in this city. In addition, there is a huge number of cars. Together with these generous suppliers of smoke and soot, both elements of smog formation that played such an important role in Donora act: temperature inversions and the mountainous nature of the terrain. [...]
The Norilsk industrial region is located in the extreme northwestern part of the Central Siberian Plateau, due to which it is characterized by the presence of sharply continental arctic climate(average annual temperature -9.9°С, average temperature July +14.0°C, and January -27.6°C. Winter in Norilsk lasts about 9 months. Long winters have little snow, and air temperature inversions are frequent. During periods of cyclonic activity and snowstorms, wind speeds can reach 40 m/s. Summer begins after July 5-10 and lasts two to three weeks; the rest occurs in spring and autumn. On the plateau, up to 1000-1100 mm of precipitation falls, in depressions - slightly less than half of this amount. Approximately 2/3 of precipitation is rain. This is not bad at all, because acid precipitation is less damaging to vegetation than dry sulfur deposition.[...]
Industrial enterprises, urban transport and heat-generating installations are the cause (mainly in cities) of smog: unacceptable pollution of human-inhabited outdoor air environment due to the release of harmful substances into it by the indicated sources under unfavorable weather conditions (lack of wind, temperature inversion, etc.).[...]
The next stage of research into the properties of the DBC coenzyme was the study of circular dichroism (CD) curves of the coenzyme and its analogues. Although a clear interpretation of CD curves does not yet exist, examination of the CD spectra of various corrin compounds shows that there is a parallel between CD curves and ultraviolet spectra. Particularly important was the property of CD curves to undergo inversion upon substitution of the cross-axial ligands X and Y, while such substitution has little effect on the ultraviolet spectra. The results we obtained when studying the CD curves of 5-deoxynucleoside analogues of the DBA coenzyme turned out to be interesting. In this case, it turned out that at 300-600 nm the curves of the CD coenzyme and analogues are almost identical, and in the region of 230-300 nm in some cases a large difference is observed. These results certainly need to be taken into account in a comparative study of CD curves of B-dependent enzymes. [...]
In table Table 5.3 provides estimates of the amounts of five major air pollutants emitted into the atmosphere over the continental United States in selected years. About 60% of pollutants are brought from other areas, industry provides 20%, power plants - 12%, heating - 8%. While the greatest direct threat to human health comes from pollutants that accumulate in high concentrations during temperature inversions over cities such as Tokyo, Los Angeles and New York (layers of warm air prevent pollutants from rising and dissipating), their impact on a national scale and the whole world also cannot be neglected. As can be seen from table. 5.3, the amount of pollutants peaked in the early 70s, and by the end of the decade it had fallen by about 5%, with the amount of suspended particles falling by 43%. Air quality in the United States is improving: 1980 report from the Quality Council environment notes that in 23 cities, the number of "unhealthy" or hazardous days (as measured by a rather arbitrary air cleanliness standard) fell by 18% from 1974 to 1978. It appears that fuel and energy conservation measures and the installation of federally mandated air pollution control devices have at least stopped the increase in air pollution. A similar stop in the growth of air pollution has been noted in Europe.[...]
The main reason for the formation of photochemical fog is severe pollution of urban air with gas emissions from chemical industry and transport enterprises and mainly from vehicle exhaust gases. For every kilometer of travel, a passenger car emits about 10 g of nitrogen oxide. In Los Angeles, where over 4 million cars have accumulated, they emit about 1 thousand tons of this gas per day into the air. In addition, temperature inversions are frequent here (up to 260 days a year), contributing to air stagnation over the city. Photochemical fog occurs in polluted air as a result of photochemical reactions occurring under the influence of short-wave (ultraviolet) solar radiation on gas emissions. Many of these reactions create substances that are significantly more toxic than the original ones. The main components of photochemical smog are photooxidants (ozone, organic peroxides, nitrates, nitrites, peroxylacetyl nitrate), nitrogen oxides, carbon monoxide and dioxide, hydrocarbons, aldehydes, ketones, phenols, methanol, etc. These substances are always present in the air in smaller quantities large cities, in photochemical smog their concentration often far exceeds the maximum permissible standards.[...]
Hydrocarbons, sulfur dioxide, nitrogen oxide, hydrogen sulfide and others gaseous substances, entering the atmosphere, they are removed from it relatively quickly. Hydrocarbons are removed from the atmosphere due to the dissolution of seas and oceans in water and subsequent photochemical and biological processes occurring with the participation of microorganisms in water and soil. Sulfur dioxide and hydrogen sulfide, oxidizing to sulfates, are deposited on the surface of the earth. Possessing acidic properties, they are sources of corrosion of various structures made of concrete and metal; they also destroy products made of plastics, artificial fibers, fabrics, leather, etc. A significant amount of sulfur dioxide is absorbed by vegetation and dissolved in the water of the seas and oceans. Carbon monoxide is oxidized to carbon dioxide, which is intensively absorbed by vegetation in the process of photochemical synthesis. Nitrogen oxides are removed due to reduction and oxidation reactions (with strong solar radiation and temperature inversion, they form smog that is dangerous for breathing).
An abnormal increase in TEMPERATURE with altitude. Normally, air temperature decreases with increasing altitude above ground level. The average rate of decrease is 1 °C for every 160 m. Under certain weather conditions, the opposite situation is observed. On a clear, calm night with an anticyclone, cold air can roll down the slopes and collect in the valleys, and the air temperature will be lower near the valley bottom than 100 or 200 m above. Above the cold layer there will be warmer air, which will likely form a cloud or light fog. becomes clear in the example of smoke rising from a fire. The smoke will rise vertically and then, when it reaches the "inversion layer", will bend horizontally. If this situation is created on a large scale, the dust and dirt that rises into the atmosphere remain there and, when accumulated, lead to serious pollution.
View value Temperature Inversion in other dictionaries
Inversion- inversions, w. (Latin inversio - turning over) (linguistic, lit.). Rearrangement of words that violates their usual order in a sentence; construction with reversed word order, e.g. Dull........
Ushakov's Explanatory Dictionary
Inversion J.— 1. Changing the usual word order in a sentence for a semantic or stylistic purpose. 2. An increase in air temperature in the upper layers of the atmosphere instead of what is usually observed........
Explanatory Dictionary by Efremova
Inversion- -And; and. [lat. inversio - rearrangement] Changing the normal position of elements, placing them in reverse order. I. in word arrangement (linguistic, lit.; change of order........
Kuznetsov's Explanatory Dictionary
Adaptation Temperature- A. thermoreceptors to the action of constant temperature, manifested by a decrease in their sensitivity.
Large medical dictionary
Botkin Temperature Curve— (S.P. Botkin) type of temperature curve in patients with typhoid fever, characterized by undulation, reflecting the cyclic course of the infectious process.
Large medical dictionary
Wunderlich Temperature Curve- (C. R. A. Wunderlich, 1815-1877, German doctor) temperature curve in patients with typhoid fever, characterized by a gradual rise, prolonged constant fever and lytic decline.......
Large medical dictionary
Inversion- (Latin inversio, inversion, rearrangement) in genetics, intrachromosomal rearrangement, in which the order of loci in part of the chromosome is reversed.
Large medical dictionary
Sleep Inversion— see Perversion of sleep.
Large medical dictionary
Inversion of Electrocardiogram Elements- a shift in the polarity of the electrocardiogram elements in the direction opposite to that usual for a given lead.
Large medical dictionary
Kildyushevsky Temperature Curve- (I.S. Kildyushevsky, born in 1860, Russian doctor) a variant of the temperature curve in patients with typhoid fever, characterized by a rapid high rise followed by a gradual decrease.
Large medical dictionary
Mutation Temperature— see Temperature-sensitive mutation.
Large medical dictionary
Inversion— geomagnetic field - a change in the direction (polarity) of the Earth’s magnetic field to the opposite, observed at time intervals from 500 thousand years to 50 million years. In our era........
Population Inversion- a nonequilibrium state of a substance in which the population of the upper of a pair of energy levels of one type of atoms (ions, molecules) that make up the substance exceeds......
Big encyclopedic dictionary
Temperature Inversion- an increase in air temperature with height in a certain layer of the atmosphere instead of the usual decrease. There are surface temperature inversions that begin immediately........
Large encyclopedic dictionary
Combined Inversion (cf)- the operation of transition from particles of the system to antiparticles (charge conjugation, C) with a simultaneous change in the signs of the spatial coordinates of the particles (spatial........
Large encyclopedic dictionary
International Practical Temperature Scale (MPTS-68)- established in 1968 by the International Committee of Weights and Measures on the basis of 11 primary reproducible temperature points (triple point of water, boiling point of neon, solidification......
Large encyclopedic dictionary
Sensitivity Temperature— (s. thermoaesthetica) Ch. to changes in ambient temperature.
Large medical dictionary
Practical Temperature Scale- See International Practical Temperature Scale.
Large encyclopedic dictionary
Spatial Inversion (p)— changing the signs of the spatial coordinates of particles to the opposite: x ? x, y ? y, z ? z; it turns out to be a near-mirror reflection of the coordinates of the particles relative to three mutually perpendicular........
Large encyclopedic dictionary
Temperature Inversion— see Temperature inversion.
Large encyclopedic dictionary
Thermodynamic Temperature Scale- (Kelvin scale) - an absolute temperature scale that does not depend on the properties of the thermometric substance (the reference point is the absolute zero of temperature). Construction of thermodynamic temperature........
Large encyclopedic dictionary
Inversion- (from Latin inversio - turning over), a type of chromosomal rearrangement consisting in turning over a section of genetic. material by 180. Leads to a change in the alternation of sites in........
Biological encyclopedic dictionary
Temperature Inversion- temperature inversion - an increase in air temperature with height in a certain layer of the troposphere. Inversions occur in the surface layer of air, as well as in the free atmosphere........
Geographical encyclopedia
Temperature History of the Earth— - now the average air temperature of the Earth is 14.2.3 billion years ago, it was 71.600 million years ago 20.
Historical Dictionary
Inversion— - a transformation that takes each point of the Flat Plane to a point A" lying on the ray OA such that OA" - OA = k, where k is some constant real number. Point Onaz.........
Mathematical Encyclopedia
Inversion- change in the usual order of things, rearrangement; sexual inversion means homosexuality.
Sexological dictionary
Inversion- change in the usual order of things, rearrangement; sexual inversion means homosexuality.(
Paragliders associate a lot of impressions and memories with the concept of “inversion”. Usually they talk about this phenomenon with regret, something like “again, a low inversion prevented me from flying a good route” or “I ran into an inversion and could not gain more.” Let's look at this phenomenon, is it so bad? And with the usual mistakes that paragliders make when talking about “inversion”.
So let's start with Wikipedia:
Inversion in meteorology - means the anomalous nature of changes in any parameter in the atmosphere with increasing altitude. Most often this applies to temperature inversion, that is, to an increase in temperature with height in a certain layer of the atmosphere instead of the usual decrease.
So it turns out that when we talk about “inversion”, we are talking specifically about temperature inversion. That is, about an increase in temperature with height in a certain layer of air.– This point is very important to firmly understand, because speaking about the state of the atmosphere, we can highlight that for the lower part of the atmosphere (before the tropopause):
- Normal condition– when the air temperature increases with altitude – decreases. For example, the average rate of temperature decrease with height for a standard atmosphere is accepted by ICAO as 6.49 degrees K per km.
- Not normal condition remains constant(isothermia)
- Also not a normal state– when the temperature increases with altitude increases (temperature inversion)
The presence of isothermia or real inversion in some layer of air means that the atmospheric gradient here is zero or even negative, and this clearly indicates the STABILITY of the atmosphere ().
A freely rising volume of air, entering such a layer, very quickly loses its difference in temperature between it and the environment. (The air rising is cooled along a dry or moist adiabatic gradient, and the air surrounding it does not change temperature or even heats up. That temperature difference, which was the reason for the excess of Archimedes' force over the force of gravity is quickly leveled out and the movement stops).
Let's give an example, suppose we have a certain volume of air that has overheated at the surface of the earth, relative to the air surrounding it, by 3 degrees K. This volume of air, breaking away from the ground, generates a thermal bubble (thermal). At the initial stage, its temperature is 3 degrees higher, and therefore the density for the same volume, compared to the air around it, is lower. Consequently, the force of Archimedes will exceed the force of gravity, and the air will begin to move upward with acceleration (float). Floating up atmospheric pressure will fall all the time, the floating volume will expand, and as it expands it will cool according to the dry adiabatic law (air mixing is usually neglected for large volumes).
How long will it take to float? - depends on how quickly the environment around it cools at altitude. If the law of change in the cooling of the environment is the same as the dry adiabatic law, then the initial “overheating relative to the environment” will be maintained all the time, and our rising bubble will accelerate all the time (the friction force will increase with speed, and at significant speeds it can no longer be neglected , the acceleration will decrease).
But such conditions are extremely rare; most often we have an atmospheric gradient in the region of 6.5 – 9 degrees K per km. Let's take 8 degrees K per km as an example.
The difference between the atmospheric gradient and dry adiabatic = 10-8 = 2 degrees K per km, then at an altitude of 1 km from the surface, from the initial overheating of 3 degrees, only 1 remained. (our bubble cooled by 9.8 = 10 degrees, and the surrounding air by 8). Another 500m of ascent and the temperatures will become equal. That is, at an altitude of 1.5 km, the temperature of the bubble and the temperature of the surrounding air will be the same, the Archimedes force and the force of gravity will be balanced. What will happen to the bubble? In all paragliding books, they write that it will remain at this level. Yes, ultimately, theoretically, this is exactly what will happen. But the dynamics of the process are also important for us flying.
The bubble will not hang at a new, equilibrium level immediately. And if there weren’t those phenomena that are neglected when describing the rise of a bubble (friction force, mixing with the surrounding air, heat exchange with the surrounding air), it would never have frozen :).
At first, “by inertia” it will jump above the equilibrium level (it was accelerating all the time it was rising and already has a decent speed, and therefore a reserve of kinetic energy. Rising above this level (1.5 km), the gradient will work in the opposite direction, then there is our volume of air will cool faster than the surrounding one, the force of gravity will exceed the force of Archimedes, and the resulting force will act downward, slowing down (together with the friction force) its movement. At some height, their action will completely stop our bubble and it will begin. downward movement. If we completely neglect the friction force and assume that the air does not mix with the surrounding air and does not exchange energy, then it would fluctuate up and down from 0 to 3000 m. But in reality, of course, this does not happen. Friction force, heat exchange and mixing are also present. fade quickly and are limited especially quickly by layers with different gradients.
Let's now consider the same example, only with an inversion layer, a gradient in -5 degrees K per km (remember that in meteorology the gradient is with the opposite sign), at an altitude of 750m it is 300m thick.
Then in the first 750m our bubble will lose 1.5 degrees of overheating (10-8 = 2 degrees K per km. 2*0.75 = 1.5 degrees), rising further it will continue to cool by 1 degree for every 100m, and starting from a height of 750m , the surrounding air only increases its temperature. This means the difference between the gradients. 10–5=15 degrees K per km, or 1.5 degrees per 100m. And after the next 100m (at an altitude of 850 meters), the temperature of the bubble will be equal to the environment.
This means that the inversion layer with a gradient of -5 degrees K per km quickly stopped the bubble. (It will also quickly extinguish the inertia of the bubble, ideally after 200m, but in fact, taking into account friction, mixing and heat transfer, much earlier).
We see that the inversion layer limits the bubble oscillations (if we neglect friction, mixing and heat transfer) from the range of 0-3000m to the range of 0-1050m.
Is inversion really that bad? If it's at a low altitude and slows down our thermals, that's bad. If it is at a sufficiently high altitude and protects against the rise of air into instability zones in which condensation occurs, and where the moisture-adiabatic gradient is less than atmospheric, then inversion is good.
What causes temperature inversion?
After all, strictly speaking, for the thermodynamic equilibrium of the atmosphere to the level of the tropopause, this is not a normal state.
There are 2 types of inversion according to the place of manifestation:
- ground level (one that starts from the surface of the earth)
- inversion at height (some layer at height)
And we can distinguish 4 types of inversion, according to the types of its occurrence. we can easily encounter all of them in everyday life and on flights:
- ground-level radiation cooling
- leak inversion
- advective transport inversion
- subsidence inversion
WITH surface inversion It’s simple, it’s also called radiation cooling inversion or night inversion. The surface of the earth, with the weakening of heat from the sun, quickly cools (including due to infrared radiation). The cooled surface also cools the adjacent layer of air. Since air does not tolerate heat well, above a certain altitude this cooling is no longer felt.
Surface inversion
The thickness of the layer, the intensity of its supercooling depends on:
- duration of cooling, the longer the night, the more the surface and the adjacent layer of air cools. In autumn and winter, surface inversions are thicker and have a more pronounced gradient.
- cooling rate, for example, if there is cloudiness, then part of the infrared radiation with which heat escapes is reflected back to the ground, and the cooling intensity is noticeably reduced (cloudy nights are warm).
- The heat capacity of the underlying surface, which has a large heat capacity and has accumulated heat during the day, takes longer to cool and cools the air less (for example, warm bodies of water).
- the presence of wind near the ground, the wind mixes the air and it cools more intensely, the inversion layer (thickness) is noticeably larger.
Leak inversion- occurs when cold air flows from the slopes into the valley, displacing warmer air upward. Air can flow both from cooled slopes at night and during the day, for example from glaciers.
Leak inversion
Inversion of advective transport occurs during horizontal air transfer. For example, warm air masses on cold surfaces. Or just different air masses. A striking example is atmospheric fronts; an inversion will be observed at the front’s border. Another example is the advection of warm (at night) air from the water surface onto cold land. In autumn, such advection is often visualized by fogs. (they are called advective fogs, when moist warm air from water is transferred to cold land, or to more cold water etc.)
Occurs when external forces force some layer of air to fall down. As the air descends, it will compress (as atmospheric pressure increases) and heat up adiabatically, and it may turn out that the underlying layers have lower temperatures - an inversion will occur. This process can occur in different conditions and scale, such an inversion occurs, for example, when air settles in anticyclones, when air descends in a mountain-valley circulation, between a cloud with precipitation and the surrounding air nearby, or, for example, during a foehn. For its occurrence, a constant external influence is needed that carries out the transfer and lowering of air.
Let us now return to the myths about inversion.
Very often, paragliders talk about inversion where there is none. This is due to the fact that we are accustomed to calling any layer that noticeably slows down and delays the vertical movement of air inversion although this is not so. Just a layer with a small gradient, or isotherm, also quickly blocks the movement of air, but is not a true inversion.
The second point arose due to the fact that in books and illustrations, for clarity, they usually draw atmospheric gradients or an aerological diagram in RECTANGULAR COORDINATE SYSTEMS (RAC), where isotherms (lines of constant temperatures) are directed from bottom to top perpendicular to isobars (or lines of equal height). In such figures, inversion is any section of the stratification curve tilted to the RIGHT from vertical from bottom to top. The inversion in such coordinates is easily visible.
An example from D. Pegan’s book “Understanding the Sky.”
In practice, most people use it, for example, from the site meteo.paraplan.ru and here already, the isotherms themselves are inclined to the right, so in order to see the inversion, you need to compare the STEENness of the slope of the stratification curve with the isotherm! And doing this by eye with a quick glance is much more difficult than with a diagram in the ADP. Look at the chart below, there is a small surface inversion visible near the ground. In the 400m layer the temperature increased slightly (at an altitude of 600 meters it is about a degree warmer than at the ground) the gradient is about -2.5 degrees K per km. And at the top, NOT an inversion, but just a very small gradient, about +3.5 degrees K per km.
Inversion and Non-inversion
Due to the fact that not any tilt to the right will be an inversion on the ADC, pilots often use this word in the wrong place, which irritates true meteorologists :)
At the same time, calculated, model aerological diagrams may not predict thin inversion layers, since they average the temperature over the layer, instead of taking into account 2 layers, an inversion layer with a thickness of, for example, 100 m with a temperature difference at the lower and upper boundaries of -1 degree, an adjacent layer 900 meters with a temperature difference of +8 degrees. they will simply draw a thicker layer, 1 km - with an average gradient of 7 degrees per kilometer. While in reality there will be several different layers.
For example, as in the full-scale diagram (ADP) below. It also shows a surface inversion layer 200 m thick + an isothermal layer. And a thin inversion layer at an altitude of 2045m, and an isothermal layer at an altitude of 3120m. These thin layers are not calculated by the model, but in fact they have a strong influence on thermals.
Full-scale ADP from a balloon
Resume.
Not every part of the stratification curve inclined to the right on the ADC is an inversion, be careful! The real inversion can only be seen on an aerological diagram taken from actual atmospheric sounding data. On “model” diagrams, they may not be calculated, but only taken into account in reducing the gradient on some layer. However, in this case, their existence can be guessed if we take into account the possible factors for the occurrence of inversions.
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