What is inversion in geography. Inversion

A decrease in temperature with height can be considered the normal state of affairs for the troposphere, and temperature inversions can be considered deviations from the normal state. True, temperature inversions in the troposphere are a frequent, almost everyday phenomenon. But they capture air layers that are quite thin compared to the entire thickness of the troposphere.

Temperature inversion can be characterized by the height at which it is observed, the thickness of the layer in which there is an increase in temperature with height, and the temperature difference at the upper and lower boundaries of the inversion layer - a temperature jump. As a transitional case between the normal decrease in temperature with height and inversion, the phenomenon of vertical isothermia is also observed, when the temperature in a certain layer does not change with height.

By height, all tropospheric inversions can be divided into surface inversions And inversions in free atmosphere.

Surface inversion starts from the underlying surface itself (soil, snow or ice). Over open water, such inversions are rarely observed and are not so significant. The temperature of the underlying surface is the lowest; it increases with height, and this increase can extend to a layer of several tens or even hundreds of meters. The inversion is then replaced by a normal decrease in temperature with height.

Surface temperature inversions over land or ocean ice are largely due to nighttime radiative cooling of the underlying surface. Such inversions are called radiative . The lower layers of air are cooled from the earth's surface more than the overlying ones. Therefore, near the earth's surface the temperature drops the most and an increase in temperature with height is established.

Inversion in the free atmosphere is observed in a certain layer of air lying at a certain height above the earth's surface (Fig. 8). The base of an inversion can be at any level in the troposphere, but inversions are most common within the lower 2 km. The thickness of the inversion layer can also be very different - from a few tens to many hundreds of meters. Finally, the temperature jump at the inversion, i.e. the temperature difference at the upper and lower boundaries of the inversion layer can vary from 1° or less to 10-15° or more.

It happens that a surface inversion, extending to a considerable height, merges with an overlying inversion in the free atmosphere. Then the temperature increase begins from the earth’s surface itself and continues to high altitudes, and the temperature jump turns out to be especially significant.

It also happens that the inversion directly transforms into the overlying isotherm. Often, two (or more) inversions are observed in the free atmosphere over a particular region, separated by layers with a normal decrease in temperature.

Fig.8. Types of temperature distribution with height: A - ground inversion, b- surface isothermia, V - free atmosphere inversion

Inversions are not observed over individual points on the earth's surface. The inversion layer extends continuously over a large area, especially in the case of inversions in the free atmosphere.

Inversion in meteorology means the anomalous nature of changes in any parameter in the atmosphere with increasing altitude. Most often this refers to temperature inversion, that is, an increase in temperature with height in a certain layer of the atmosphere instead of the usual decrease.

There are two types of inversion:

Surface temperature inversions starting directly from the earth's surface (the thickness of the inversion layer is tens of meters)

Temperature inversions in the free atmosphere (the thickness of the inversion layer reaches hundreds of meters)

Temperature inversion prevents vertical air movements and contributes to the formation of haze, fog, smog, clouds, and mirages. Inversion strongly depends on local terrain features. The temperature increase in the inversion layer ranges from tenths of a degree to 15-20 °C or more. Surface temperature inversions have the greatest power in Eastern Siberia and in Antarctica in winter.

Normal atmospheric conditions

Typically, in the lower atmosphere (troposphere), the air near the Earth's surface is warmer than the air above because the atmosphere is primarily heated by solar radiation through earth's surface. As altitude changes, the air temperature decreases, the average rate of decrease is 1 °C for every 160 m.

Causes and mechanisms of inversion

Under certain conditions, the normal vertical temperature gradient changes in such a way that cooler air ends up near the Earth's surface. This can happen, for example, when a warm, less dense air mass moves over a cold, more dense layer. This type of inversion occurs in the vicinity of warm fronts, as well as in areas of oceanic upwelling (upwelling is the process by which deep ocean waters rise to the surface), such as off the coast of California. With sufficient moisture in the cooler layer, fog formation under the inversion “lid” is typical.
On a clear, quiet night during an anticyclone, cold air can descend down the mountain slopes and collect in the valleys, where the resulting air temperature will be lower than 100 or 200 m higher. Above the cold layer there will be warmer air, which will likely form a cloud or light fog. Temperature inversion is clearly demonstrated by the example of smoke from a fire. The smoke will rise vertically and then bend horizontally when it reaches the “inversion layer.” If this situation is created on a large scale, dust and dirt (smog) rising into the atmosphere remain there and, when accumulated, lead to serious pollution.

Inversion of descent

A temperature inversion can occur in the free atmosphere when a broad layer of air sinks and is heated by adiabatic compression, which is usually associated with subtropical high pressure areas. Turbulence can gradually lift the inversion layer to a greater height and “puncture” it, resulting in the formation of thunderstorms and even (under certain circumstances) tropical cyclones.

Consequences of temperature inversion

When the normal convection process ceases, the lower layer of the atmosphere becomes polluted. This causes problems in cities with large emissions. Inversion effects often occur in large cities such as Mumbai (India), Los Angeles (USA), Mexico City (Mexico), Sao Paulo (Brazil), Santiago (Chile) and Tehran (Iran). Small cities such as Oslo (Norway) and Salt Lake City (USA), located in valleys of hills and mountains, are also influenced by the blocking inversion layer. With a strong inversion, air pollution can cause respiratory diseases. The Great Smog of 1952 in London is one of the most serious such events - more than 10 thousand people died because of it.
Temperature inversions pose a danger to aircraft taking off, as engine thrust is reduced when the aircraft enters the overlying layers of warmer air.
In winter, an inversion can lead to hazardous phenomena nature. Very severe frosts in the anticyclone. Freezing rain when Atlantic and southern cyclones emerge (especially during the passage of their warm fronts).

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........
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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........
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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........
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Adaptation Temperature- A. thermoreceptors to the action of constant temperature, manifested by a decrease in their sensitivity.
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Botkin Temperature Curve- (S.P. Botkin) type of temperature curve in patients with typhoid fever, characterized by waveform, reflecting the cyclic course of the infectious process.
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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.......
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Inversion- (Latin inversio, inversion, rearrangement) in genetics, intrachromosomal rearrangement, in which the order of loci in part of the chromosome is reversed.
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Sleep Inversion— see Perversion of sleep.
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Inversion of Electrocardiogram Elements- a shift in the polarity of the electrocardiogram elements in the direction opposite to that usual for a given lead.
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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.
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Mutation Temperature— see Temperature-sensitive mutation.
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Inversion — geomagnetic field- a change in the direction (polarity) of the Earth's magnetic field to the opposite is observed at time intervals from 500 thousand years to 50 million years. In our era........

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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........
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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........
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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......
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Sensitivity Temperature- (s. thermoaesthetica) Ch. to temperature change environment.
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Practical Temperature Scale- See International Practical Temperature Scale.
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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........
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Temperature Inversion— see Temperature inversion.
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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........
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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........
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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........
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Temperature History of the Earth- - Now average temperature Earth's air 14.2, 3 billion years ago was 71, 600 million years ago 20.
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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.........
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Inversion- change in the usual order of things, rearrangement; sexual inversion means homosexuality.
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Inversion- change in the usual order of things, rearrangement; sexual inversion means homosexuality.(

The weather in a given area has a strong influence on human life, so information about the condition earth's atmosphere is always useful from an economic and health safety point of view. Temperature inversion is one of the types of conditions in the lower layers of the atmosphere. What it is and where it manifests itself is discussed in the article.

What is temperature inversion?

This concept means an increase in air temperature as the height from the earth's surface increases. This seemingly harmless definition entails quite serious consequences. The fact is that air can be considered an ideal gas, for which the pressure at a fixed volume is inversely related to temperature. Since during a temperature inversion, the temperature increases with increasing altitude, which means that the air pressure decreases and its density decreases.

It is known from the school physics course that convection processes, which cause vertical mixing in the volume of a fluid substance located in a gravitational field, occur if the lower layers are less dense than the upper ones (hot air always rises upward). Thus, temperature inversion prevents convection in the lower atmosphere.

Normal atmospheric conditions

As a result of numerous observations and measurements, it was found that in the temperate climate zone of our planet, air temperature decreases by 6.5 °C for every kilometer of altitude, that is, by 1 °C for an increase in altitude by 155 meters. This fact is due to the fact that heating of the atmosphere occurs not as a result of the passage of solar rays through it (air is transparent for the visible spectrum of electromagnetic radiation), but as a result of its absorption of re-emitted energy in the infrared range from the surface of the earth and water. Therefore, the closer the air layers are to the ground, the more they warm up on a sunny day.

In the tropical area climate zone With increasing altitude, the air cools more slowly than the indicated figures (by approximately 1 °C per 180 m). This is due to the presence of trade winds in these latitudes, which transfer heat from the equatorial regions to the tropics. In this case, heat flows from the upper layers (1-1.5 km) to the lower ones, which prevents the rapid drop in air temperature with increasing altitude. In addition, the thickness of the atmosphere in the tropical zone is greater than in the temperate zone.

Thus, the normal state of atmospheric layers is to cool them with increasing altitude above sea level. This state favors mixing and circulation of air in the vertical direction due to convection processes.

Why can the upper air layers be warmer than the lower ones?

In other words, why does temperature inversion occur? This happens for the same reason as the existence of normal atmospheric conditions. The earth has higher value thermal conductivity than air. This means that at night, when there are no clouds in the sky, it quickly cools down and those atmospheric layers that are in direct contact with the earth’s surface also cool. The result is the following picture: a cold surface of the earth, a cold layer of air in the immediate vicinity of it and a warm atmosphere at a certain height.

What is temperature inversion and where does it occur? The described situation often occurs in lowlands, in absolutely any area and at any latitude in the morning. The lowland area is protected from horizontal movements of air masses, that is, from the wind, so the air cooled overnight creates a locally stable atmosphere. The phenomenon of temperature inversion can be observed in mountain valleys. In addition to the described process of night cooling, its formation in the mountains is also facilitated by the “sliding” of cold air from the slopes to the plains.

The lifetime of a temperature inversion can last from several hours to several days. Normal atmospheric conditions are established as soon as the earth's surface warms up.

How dangerous is the phenomenon in question?

The state of the atmosphere in which a temperature inversion exists is stable and windless. This means that if any emissions into the atmosphere or evaporation of toxic substances occur in a given territory, they do not disappear anywhere, but remain in the air above the area in question. In other words, the phenomenon of temperature inversion in the atmosphere contributes to a manifold increase in the concentration of toxic substances in it, which poses a huge danger to human health.

The described situation often occurs over large cities and megalopolises. For example, cities such as Tokyo, New York, Athens, Beijing, Lima, Kuala Lumpur, London, Los Angeles, Bombay, the capital of Chile - Santiago and many other cities around the world often suffer from the consequences of temperature inversion. Due to the large concentration of people, industrial emissions in these cities are gigantic, which leads to the appearance of smog in the air, disrupting visibility and posing a threat not only to health, but also to human life.

Thus, in 1952 in London and in 1962 in the Ruhr Valley (Germany), several thousand people died as a result of a long period of temperature inversion and significant emissions of sulfur oxides into the atmosphere.

Capital of Peru, Lima

Expanding the question of what temperature inversion is in geography, it is interesting to cite the situation in the capital of Peru. It is located on the shore Pacific Ocean and at the foot of the Andes mountains. The coast near the city is washed by Humboldt, which leads to a strong cooling of the earth's surface. The latter, in turn, contributes to the cooling of the lowest air layers and the formation of fogs (as the air temperature decreases, the solubility of water vapor in it decreases, the latter manifests itself in dew and fog formation).

As a result of the described processes, a paradoxical situation arises: the coast of Lima is covered with fog, which prevents the sun's rays from heating the earth's surface. Therefore, the state of temperature inversion is so stable (horizontal air circulation is hampered by mountains) that it almost never rains here. Last fact explains why the coast of Lima is practically a desert.

How to behave if you receive information about an unfavorable state of the atmosphere?

If a person lives in a large city and he has received information about the existence of a temperature inversion in the atmosphere, then it is recommended, if possible, not to go outside in the morning, but to wait until the earth warms up. If such a need arises, then you should use personal protective equipment for the respiratory organs (gauze bandage, scarf) and not stay long time on open air.

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.– It is very important to firmly understand this point, 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). On 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 Atmosphere 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 downwards, braking (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 this, of course, does not happen. Friction force, heat exchange and mixing - there are also fluctuations 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 boundary. 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 if 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

Summary.

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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