In the troposphere, the air temperature decreases with height, as noted, by an average of 0.6 "C for every 100 m of height. However, in ground layer The temperature distribution can be different: it can decrease, increase, or remain constant. The vertical temperature gradient (VTG) gives an idea of the distribution of temperature with height:
VGT = (/„ - /B)/(ZB -
where /n - /v - temperature difference at the lower and upper levels, °C; ZB - ZH - height difference, m. Usually the VGT is calculated per 100 m of height.
In the surface layer of the atmosphere, the VGT can be 1000 times higher than the average for the troposphere
The value of VGT in the surface layer depends on weather conditions(in clear weather it is greater than in cloudy weather), time of year (more in summer than in winter) and time of day (more during the day than at night). Wind reduces the VGT, since when the air is mixed, its temperature at different altitudes is equalized. Above moist soil, the VGT in the ground layer sharply decreases, and above bare soil ( steam field) VHT is greater than over dense crops or meadows. This is due to differences in the temperature regime of these surfaces (see Chapter 3).
As a result of a certain combination of these factors, the VGT near the surface, calculated per 100 m of height, can be more than 100 °C/100 m. In such cases, thermal convection occurs.
The change in air temperature with height determines the sign of the VGT: if VGT > 0, then the temperature decreases with distance from the active surface, which usually happens during the day and summer (Fig. 4.4); if VGT = 0, then the temperature does not change with height; if VGT< 0, то температура увеличивается с высотой и такое распределение температуры называют инверсией.
Depending on the conditions for the formation of inversions in the surface layer of the atmosphere, they are divided into radiative and advective.
1. Radiative inversions occur during radiative cooling earth's surface. Such inversions form at night during the warm season, and are also observed during the day in winter. Therefore, radiation inversions are divided into nighttime (summer) and winter.
Night inversions are established in clear, quiet weather after the radiation balance passes through 0 1.0...1.5 hours before sunset. During the night they intensify and reach their greatest power before sunrise. After sunrise, the active surface and air warm up, which destroys the inversion. The height of the inversion layer is most often several tens of meters, but under certain conditions (for example, in closed valleys surrounded by significant elevations) it can reach 200 m or more. This is facilitated by the flow of cooled air from the slopes into the valley. Cloudiness weakens the inversion, and wind speeds of more than 2.5...3.0 m/s destroy it. Under the canopy of dense grass, crops, and forests in summer, inversions are also observed during the day.
Nighttime radiation inversions in spring and autumn, and in some places in summer, can cause a decrease in soil and air surface temperatures to negative values (freezing), which causes damage to many cultivated plants.
Winter inversions occur in clear, calm weather under conditions short day when the cooling of the active surface continuously increases every day; they may persist for several weeks, weakening slightly during the day and becoming stronger again at night.
Radiation inversions are especially intensified under highly heterogeneous terrain. The cooling air flows into lowlands and basins, where weakened turbulent mixing contributes to its further cooling. Radiation inversions associated with terrain features are usually called orographic.
2. Advective inversions are formed when warm air advects (moves) onto a cold underlying surface, which cools the adjacent layers of advancing air. These inversions also include snow inversions. They arise during the advection of air having a temperature above O "C onto a surface covered with snow. A decrease in temperature in the lowest layer in this case is associated with the heat consumption for melting snow.
INDICATORS OF TEMPERATURE REGIME IN A GIVEN LOCATION AND THE HEAT REQUIREMENT OF PLANTS
When assessing the temperature regime of a large territory or individual location, temperature characteristics for a year or for individual periods (growing season, season, month, decade and day) are used. The main ones of these indicators are the following.
Average daily temperature is the arithmetic mean of temperatures measured during all observation periods. At weather stations Russian Federation air temperature is measured eight times a day. By summing the results of these measurements and dividing the sum by 8, the average daily air temperature is obtained.
Average monthly temperature is the arithmetic mean of the average daily temperatures for the entire day of the month.
Average annual temperature- this is the arithmetic mean of the average daily (or average monthly) temperatures for the entire year.
The average code air temperature gives only a general idea of the amount of heat; it does not characterize the annual temperature variation. Thus, the average annual temperature in the south of Ireland and in the steppes of Kalmykia, located at the same latitude, is close (9°C). But in Ireland the average January temperature is 5...8 "C, and the meadows are green all winter here, and in the steppes of Kalmykia the average January temperature is -5...-8 °C. In the summer in Ireland it is cool: 14 °C, and The average July temperature in Kalmykia is 23...26 °C.
Therefore for more full characteristics The annual variation of temperature in a given place uses data on the average temperature of the coldest (January) and warmest (July) months.
However, all averaged characteristics do not give an accurate idea of the daily and annual temperature variations, i.e., precisely the conditions that are especially important for agricultural production. In addition to the average temperatures are the maximum and minimum temperatures, amplitude. For example, knowing the minimum temperature in the winter months, one can judge the overwintering conditions of winter crops and fruit and berry plantings. Data about maximum temperature show in winter the frequency of thaws and their intensity, and in summer - the number of hot days when damage to grain is possible during the filling period, etc.
Extreme temperatures are distinguished: absolute maximum (minimum) - the highest (lowest) temperature for the entire observation period; the average of the absolute maximums (minimums) - the arithmetic mean of the absolute extremes; average maximum (minimum) - the arithmetic average of all extreme temperatures, for example, for a month, season, year. Moreover, they can be calculated both for a long-term observation period and for an actual month, year, etc.
The amplitude of the daily and annual variations in temperature characterizes the degree of continental climate: the greater the amplitude, the more continental the climate.
The temperature regime in a given area for a certain period is also characterized by the sums of average daily temperatures above or below a certain limit. For example, in climate reference books and atlases the sums of temperatures above 0, 5, 10 and 15 °C are given, as well as below -5 and -10 °C.
A visual representation of the geographic distribution of temperature indicators is provided by maps on which isotherms are drawn - lines of equal temperature values or sums of temperatures (Fig. 4.7). Maps, for example, of temperature sums are used to justify the placement of crops (plantings) of cultural plants with different heat requirements.
To clarify the thermal conditions necessary for plants, sums of day and night temperatures are also used, since the average daily temperature and its sums neutralize thermal differences in the daily variation of air temperature.
Studying the thermal regime separately for day and night has deep physiological significance. It is known that all processes occurring in the plant and animal world are subject to natural rhythms determined by external conditions, that is, they are subject to the law of the so-called “biological” clock. For example, according to (1964), for optimal growth conditions for tropical plants, the difference between day and night temperatures should be 3...5 ° C, for plants temperate zone-5...7, and for desert plants - 8 °C or more. The study of day and night temperatures acquires special meaning for increasing the productivity of agricultural plants, which is determined by the relationship between two processes - assimilation and respiration, occurring in the light and dark hours of the day that are qualitatively different for plants.
The average day and night temperatures and their sums indirectly take into account the latitudinal variability of day and night lengths, as well as changes in the continentality of the climate and the influence of various relief forms on the temperature regime.
The sums of average daily air temperatures, close for a pair of weather stations located at approximately the same latitude, but significantly different in longitude, i.e., located in different continental climate conditions, are given in Table 4.1.
In more continental eastern regions the sums of daytime temperatures are 200...500 °C higher, and the sums of night temperatures are 300 °C less than in the western and especially maritime regions, which explains long ago known fact- acceleration of the development of agricultural crops in a sharply continental climate.
Plant heat requirements are expressed as sums of active and effective temperatures. In agricultural meteorology, active temperature is the average daily air (or soil) temperature above the biological minimum for crop development. Effective temperature is the average daily air (or soil) temperature reduced by the biological minimum value.
Plants develop only if the average daily temperature exceeds their biological minimum, which is, for example, 5 °C for spring wheat, 10 °C for corn, 13 °C for cotton (15 °C for southern cotton varieties). The sums of active and effective temperatures are established both for individual interphase periods and for the entire growing season of many varieties and hybrids of the main agricultural crops (Table 11.1).
The sums of active and effective temperatures also express the need for warmth of poikilothermic (cold-blooded) organisms both during the ontogenetic period and throughout the century. there is a biological cycle.
When calculating the sums of average daily temperatures characterizing the heat needs of plants and poikilothermic organisms, it is necessary to introduce a correction for ballast temperatures that do not accelerate growth and development, i.e., take into account the upper temperature level for crops and organisms. For most plants and pests of the temperate zone this will be an average daily temperature exceeding 20...25 "C.
Public lesson
in natural history at 5
correctional class
Change in air temperature from heights
Developed
teacher Shuvalova O.T.
The purpose of the lesson:
To develop knowledge about measuring air temperature with height, to introduce the process of cloud formation and types of precipitation.
During the classes
Availability of a textbook, workbook, diary, pen.
2. Testing students' knowledge
We are studying the topic: air
Before we start studying new material, let’s remember the material we covered, what do we know about air?
Frontal survey
Air composition
Where do these gases come from in the air: nitrogen, oxygen, carbon dioxide, impurities.
Properties of air: occupies space, compressibility, elasticity.
Air weight?
Atmospheric pressure, its change with altitude.
Heating the air.
3. Learning new material
We know that heated air rises. Do we know what happens to the heated air next?
Do you think the air temperature will decrease with height?
Lesson topic: change in air temperature with altitude.
Objective of the lesson: to find out how air temperature changes with altitude and what are the results of these changes.
An excerpt from the Swedish writer’s book “Nils’s Wonderful Journey with the Wild Geese” about a one-eyed troll who decided “I’ll build a house closer to the sun - let it warm me.” And the troll got to work. He collected stones everywhere and piled them on top of each other. Soon the mountain of their stones rose almost to the very clouds.
Now, that's enough! - said the troll. Now I will build myself a house on the top of this mountain. I will live right next to the sun. I won’t freeze next to the sun! And the troll went up the mountain. Just what is it? The higher he goes, the colder it gets. Made it to the top.
“Well,” he thinks, “it’s a stone’s throw from here to the sun!” And because of the cold, the tooth does not touch the tooth. This troll was stubborn: once it gets into his head, nothing can knock it out. I decided to build a house on the mountain, and I built it. The sun seems to be close, but the cold still penetrates to the bones. That's how this stupid troll froze.
Explain why the stubborn troll froze.
Conclusion: the closer the air is to the earth’s surface, the warmer it is, and with height it becomes colder.
When rising to a height of 1500m, the air temperature rises by 8 degrees. Therefore, outside the plane at an altitude of 1000m the air temperature is 25 degrees, and at the surface of the earth at the same time the thermometer shows 27 degrees.
What's the matter here?
The lower layers of air, heating up, expand, reduce their density and, rising upward, transfer heat to the upper layers of the atmosphere. This means that the heat coming from the surface of the earth is poorly retained. This is why it becomes colder, not warmer, outside the plane, which is why the stubborn troll froze.
Card demonstration: low and high mountains.
What differences do you see?
Why tops high mountains covered with snow, but there is no snow at the foot of the mountains? The appearance of glaciers and eternal snow on the tops of mountains is associated with changes in air temperature with height, the climate becomes more severe, and the climate changes accordingly. vegetable world. At the very top, near the high mountain peaks, there is a kingdom of cold, snow and ice. Mountain peaks in the tropics are covered with eternal snow. The boundaries of eternal snow in the mountains are called the snow line.
Table demonstration: mountains.
Look at the card with pictures of different mountains. Is the height of the snow line the same everywhere? What is this connected with? The height of the snow line varies. In the northern regions it is lower, and in the southern regions it is higher. This line is not drawn on the mountain. How can we define the concept of “snow line”.
The snow line is the line above which the snow does not melt even in summer. Below the snow line there is a zone characterized by sparse vegetation, then there is a natural change in the composition of the vegetation as it approaches the foot of the mountain.
What do we see in the sky every day?
Why do clouds form in the sky?
The heated air, rising, carries away water vapor invisible to the eye into more high layer atmosphere. As you move away from the earth's surface, the air temperature drops, the water vapor in it cools, and tiny droplets of water form. Their accumulation leads to the formation of a cloud.
TYPES OF CLOUDS:
Cirrus
Layered
Cumulus
Demonstration of a card with types of clouds.
Cirrus clouds are the tallest and thinnest clouds. They swim very high above the ground, where it is always cold. These are beautiful and cold clouds. The blue sky shines through them. They look like the long feathers of fairy-tale birds. That's why they are called pinnate.
Stratus clouds are solid, pale gray. They cover the sky with a monotonous gray blanket. Such clouds bring bad weather: snow, drizzling rain for several days.
Rain Cumulus clouds- large and dark, they rush after each other as if in a race. Sometimes the wind carries them so low that the clouds seem to touch the roofs.
Rare cumulus clouds are the most beautiful. They resemble mountains with dazzling white peaks. And they are interesting to watch. Cheerful cumulus clouds run across the sky, constantly changing. They look either like animals, or like people, or like some kind of fairy-tale creatures.
Demonstration of a card with various types clouds
Determine which clouds are shown in the pictures?
Under certain conditions of atmospheric air, precipitation falls from clouds.
What kind of precipitation do you know?
Rain, snow, hail, dew and others.
The smallest droplets of water that make up the clouds, merging with each other, gradually increase in size, become heavy and fall to the ground. In summer it's raining, in winter - snow.
What is snow made of?
Snow is made up of ice crystals different shapes- snowflakes, mostly six-pointed stars, fall from clouds when the air temperature is below zero degrees.
Often in warm time hail falls during a rainstorm - precipitation in the form of pieces of ice, most often irregular in shape.
How does hail form in the atmosphere?
Droplets of water falling on greater height, freeze and ice crystals grow on them. Falling down, they collide with drops of supercooled water and increase in size. Hail can cause a lot of damage. It knocks out crops, denudes forests, knocking down foliage, and kills birds.
4.Total of the lesson.
What new did you learn about air in the lesson?
1. Decrease in air temperature with altitude.
2. Snow line.
3.Types of precipitation.
5. Homework assignment.
Learn the notes in your notebook. Observing clouds and sketching them in a notebook.
6. Consolidation of what has been learned.
Independent work with text. Fill in the gaps in the text using reference words.
Task:
It is known that at an altitude of 750 meters above sea level the temperature is +22 o C. Determine the air temperature at the altitude:
a) 3500 meters above sea level
b) 250 meters above sea level
Solution:
We know that when the altitude changes by 1000 meters (1 km), the air temperature changes by 6 o C. Moreover, with an increase in altitude, the air temperature decreases, and with a decrease, it increases.
a) 1. Determine the difference in heights: 3500 m -750 m = 2750 m = 2.75 km
2. Determine the difference in air temperatures: 2.75 km × 6 o C = 16.5 o C
3. Let’s determine the air temperature at an altitude of 3500 m: 22 o C - 16.5 o C = 5.5 o C
Answer: at an altitude of 3500 m the air temperature is 5.5 o C.
b) 1. Determine the height difference: 750 m -250 m = 500 m = 0.5 km
2. Determine the difference in air temperatures: 0.5 km × 6 o C = 3 o C
3. Determine the air temperature at an altitude of 250 m: 22 o C + 3 o C = 25 o C
Answer: at an altitude of 250 m the air temperature is 25 o C.
2. Determination of atmospheric pressure depending on altitude
Task:
It is known that at an altitude of 2205 meters above sea level Atmosphere pressure is 550 mmHg. Determine the atmospheric pressure at altitude:
a) 3255 meters above sea level
b) 0 meters above sea level
Solution:
We know that when the altitude changes by 10.5 meters, the atmospheric pressure changes by 1 mmHg. Art. Moreover, with increasing altitude, atmospheric pressure decreases, and with decreasing altitude, it increases.
a) 1. Determine the difference in heights: 3255 m - 2205 m = 1050 m
2. Determine the difference in atmospheric pressure: 1050 m: 10.5 m = 100 mm Hg.
3. Let us determine the atmospheric pressure at an altitude of 3255 m: 550 mm Hg. - 100 mm Hg. = 450 mmHg
Answer: at an altitude of 3255 m, the atmospheric pressure is 450 mm Hg.
b) 1. Determine the difference in heights: 2205 m - 0 m = 2205 m
2. Let's determine the difference in atmospheric pressure: 2205 m: 10.5 m = 210 mm Hg. Art.
3. Determine the atmospheric pressure at an altitude of 0 m: 550 mm Hg. + 210 mm Hg. Art. = 760 mm Hg. Art.
Answer: at an altitude of 0 m the atmospheric pressure is 760 mm Hg.
3. Beaufort scale
(wind speed scale)
Points | Wind speed | Wind characteristics | Wind action |
32.7 or more | moderate very strong heavy storm fierce storm | The smoke rises vertically, the leaves on the trees are motionless Light air movement, smoke tilts slightly The movement of air is felt by the face, the leaves rustle Leaves and thin branches on the trees sway Tree tops bend, dust rises Branches and thin tree trunks sway Thick branches sway, telephone wires hum The tree trunks are swaying, it’s hard to walk against the wind Are swinging big trees, small branches break Minor damage to buildings, thick branches breaking Trees break and are uprooted, damage to buildings Great destruction Devastating destruction |
Change in air temperature with altitude
Exercise 1. Determine what temperature the air mass will have, not saturated with water vapor and rising adiabatically at an altitude of 500, 1000, 1500 m, if its temperature at the surface of the earth was 15 degrees.
The temperature changes by 1° when the air mass rises for every 100 m. This value is called dry adiabatic temperature gradient. When air saturated with water vapor rises, its cooling rate decreases somewhat, since condensation of water vapor occurs, during which latent heat of vaporization is released (600 cal per 1 g of condensed water), which is used to heat this rising air. The adiabatic process occurring inside rising saturated air is called moist adiabatic. The amount of temperature decrease (increase) for every 100 m in a rising moist saturated air mass is called moist adiabatic temperature gradient g V , and the graph of temperature changes with height in such a process is called wet adiabatic. In contrast to the dry adiabatic gradient g a, the wet adiabatic gradient g b is a variable value, depending on temperature and pressure, and ranges from 0.3° to 0.9° per 100 m of height (on average 0.6° per 100 m. ). The more moisture condenses as the air rises, the smaller the value of the moisture-adiabatic gradient; with a decrease in the amount of moisture, its value approaches the dry adiabatic gradient.
The vertical temperature gradient at an altitude of 500 meters should be = 12 °. The vertical temperature gradient at an altitude of 1000 meters should be = 9 °. The vertical temperature gradient at an altitude of 1500 meters should be = 6 °. But as soon as the air begins to rise, it will become colder than the surrounding air, and the temperature difference increases with altitude.
But cold air, being heavier, tends to descend, i.e. take the original position. Since the air is unsaturated, as it rises the temperature should decrease by 1°C per 100 m.
Therefore, the temperature air mass at an altitude of 500 meters it will be = 10°C. Therefore, the temperature of the air mass at an altitude of 1000 meters will be = 5°C. Therefore, the temperature of the air mass at an altitude of 1500 meters will be = 0°C.
Determination of the height of condensation and sublimation levels
Exercise 1. Determine the height of the level of condensation and sublimation of adiabatically rising air not saturated with water vapor, if its temperature (T) and water vapor pressure (e) are known; T = 18є, e = 13.6 hPa.
The temperature of rising air, not saturated with water vapor, changes by 1° every 100 meters. First, using the curve of maximum vapor pressure versus air temperature, you need to find the dew point (φ). Then determine the difference between the air temperature and the dew point (T - f). Multiply this value by 100 m to find the condensation level. To determine the level of sublimation, you need to find the temperature difference from the dew point to the sublimation temperature and multiply this difference by 200 m.
The condensation level is the level to which it must rise before the water vapor contained in the air during adiabatic rise reaches a state of saturation (or 100% relative humidity). The height at which water vapor in the rising air becomes saturated can be found using the formula: , where T is the air temperature; f - dew point.
f = 2.064 (according to the table)
18 є - 2.064 = 15.936 є x 122 = 1994 m saturation height of water vapor.
Sublimation occurs at a temperature of - 10°.
2.064 - (-10) = 12.064 x 200 = 2413m sublimation level.
Task 2 (B). Air having a temperature of 12°C and a relative humidity of 80% passes over mountains 1500 m high. At what altitude will clouds begin to form? What are the temperatures and relative humidity air at the top of the ridge and behind the ridge?
If the relative air humidity r is known, then the height of the condensation level can be determined using Ippolitov’s formula: h = 22 (100-r) h = 22 (100-80) = 440 m the beginning of the formation of stratus clouds.
The process of cloud formation begins with the fact that a certain mass of sufficiently moist air rises upward. As you rise, the air will expand. This expansion can be considered adiabatic, since the air rises quickly, and if its volume is sufficiently large, the heat exchange between the air in question and environment there is simply no time to happen during the ascent.
When a gas expands adiabatically, its temperature decreases. So, rising up wet air will cool down. When the temperature of the cooling air drops to the dew point, the process of condensation of the steam contained in the air becomes possible. If there are a sufficient number of condensation nuclei in the atmosphere, this process begins. If there are few condensation nuclei in the atmosphere, condensation begins not at a temperature equal to the dew point, but at lower temperatures.
Having reached a height of 440m, the rising moist air will cool and condensation of water vapor will begin. Height 440m is the lower boundary of the forming cloud. The air that continues to flow from below passes through this boundary, and the process of vapor condensation will occur above the specified boundary - the cloud will begin to develop in height. The vertical development of the cloud will stop when the air stops rising; in this case, the upper boundary of the cloud will form.
The temperature at the top of the ridge is +3 °C and the relative air humidity is 100%.
local time dry adiabatic gradient
To somewhat simplify the consideration of the issue, the atmosphere is divided into three main layers. Atmospheric stratification is primarily the result of unequal changes in air temperature with height. The bottom two layers are relatively homogeneous in composition. For this reason they are usually said to form a homosphere.
Troposphere. The lower layer of the atmosphere is called the troposphere. This term itself means “sphere of rotation” and is associated with the characteristics of the turbulence of a given layer. All changes in weather and climate are the result physical processes, occurring precisely in this layer. In the 18th century, since the study of the atmosphere was limited only to this layer, it was believed that the decrease in air temperature with height found in it was also inherent in the rest of the atmosphere.
Various energy transformations occur primarily in the troposphere. Due to the continuous contact of air with the earth's surface, as well as the entry of energy into it from space, it begins to move. The upper boundary of this layer is located where the decrease in temperature with height is replaced by its increase - approximately at an altitude of 15-16 km above the equator and 7-8 km above the poles. Like the Earth itself, under the influence of the rotation of our planet, it is also somewhat flattened above the poles and swells above the equator. However, this effect is expressed much more strongly in the atmosphere than in the solid shell of the Earth.
In the direction from the Earth's surface to the upper boundary of the troposphere, the air temperature decreases. Above the equator the minimum air temperature is about -62°C, and above the poles about -45°C. However, depending on the measurement point, the temperature may be slightly different. Thus, over the island of Java at the upper boundary of the troposphere, the air temperature drops to a record low of -95°C.
The upper boundary of the troposphere is called the tropopause. More than 75% of the atmosphere's mass lies below the tropopause. In the tropics, about 90% of the mass of the atmosphere is located within the troposphere.
The tropopause was discovered in 1899, when a minimum was found in the vertical temperature profile at a certain altitude, and then the temperature increased slightly. The beginning of this increase marks the transition to the next layer of the atmosphere - the stratosphere.
Stratosphere. The term stratosphere means “layer sphere” and reflects the previous idea of the uniqueness of the layer lying above the troposphere. The stratosphere extends to a height of about 50 km above the earth's surface. Its peculiarity is, in particular, a sharp increase in air temperature compared to its exceptionally low values at the tropopause The temperature in the stratosphere rises to approximately -40 ° C. This increase in temperature is explained by the reaction of ozone formation - one of the main chemical reactions occurring in the atmosphere.
Ozone is a special form of oxygen. Unlike the usual diatomic oxygen molecule (O2). Ozone consists of its triatomic molecules (Oz). It appears as a result of the interaction of ordinary oxygen with oxygen entering the upper layers of the atmosphere.
The bulk of ozone is concentrated at altitudes of approximately 25 km, but in general the ozone layer is a highly extended shell, covering almost the entire stratosphere. In the ozonosphere, ultraviolet rays interact most frequently and most strongly with atmospheric oxygen. causes the breakdown of ordinary diatomic oxygen molecules into individual atoms. In turn, the oxygen atoms often reattach to the diatomic molecules and form ozone molecules. In the same way, individual oxygen atoms combine to form diatomic molecules. The intensity of ozone formation turns out to be sufficient for a layer of high ozone concentration to exist in the stratosphere.
The interaction of oxygen with ultraviolet rays is one of the beneficial processes in the earth's atmosphere that contributes to the maintenance of life on Earth. The absorption of this energy by ozone prevents its excessive flow to the earth's surface, where exactly the level of energy that is suitable for the existence of terrestrial life forms is created. Perhaps in the past a greater amount of energy came to the Earth than now, which influenced the emergence of primary forms of life on our planet. But modern living organisms could not withstand more than significant amount ultraviolet radiation.
The ozonosphere absorbs the part passing through the atmosphere. As a result, a vertical air temperature gradient of approximately 0.62°C per 100 m is established in the ozonosphere, i.e., the temperature increases with altitude up to the upper limit of the stratosphere - the stratopause (50 km).
At altitudes from 50 to 80 km there is a layer of the atmosphere called the mesosphere. The word "mesosphere" means "intermediate sphere", where the air temperature continues to decrease with height.
Above the mesosphere, in a layer called the thermosphere, temperatures rise again with altitude up to about 1000°C and then drop very quickly to -96°C. However, it does not drop indefinitely, then the temperature increases again.
The division of the atmosphere into separate layers is quite easy to notice by the peculiarities of temperature changes with height in each layer.
Unlike the previously mentioned layers, the ionosphere is not highlighted. according to temperature. The main feature of the ionosphere is the high degree of ionization of atmospheric gases. This ionization is caused by the absorption of solar energy by atoms of various gases. Ultraviolet and others Sun rays, carrying high-energy quanta, entering the atmosphere, ionize nitrogen and oxygen atoms - electrons located in outer orbits are detached from the atoms. By losing electrons, the atom acquires a positive charge. If an electron is added to an atom, the atom becomes negatively charged. Thus, the ionosphere is a region of electrical nature, thanks to which many types of radio communications become possible.
The ionosphere is divided into several layers, designated by the letters D, E, F1 and F2. These layers also have special names. The separation into layers is caused by several reasons, among which the most important is the unequal influence of the layers on the passage of radio waves. The lowest layer, D, mainly absorbs radio waves and thereby prevents their further propagation.
The best studied layer E is located at an altitude of approximately 100 km above the earth's surface. It is also called the Kennelly-Heaviside layer after the names of the American and English scientists who simultaneously and independently discovered it. Layer E, like a giant mirror, reflects radio waves. Thanks to this layer, long radio waves travel further distances than would be expected if they propagated only in a straight line, without being reflected from the E layer
Layer F has similar properties. It is also called Appleton's layer. Together with the Kennelly-Heaviside layer, it reflects radio waves to terrestrial radio stations. Such reflection can occur at various angles. The Appleton layer is located at an altitude of about 240 km.
The outermost region of the atmosphere is often called the exosphere.
This term refers to the existence of the outskirts of space near the Earth. It is difficult to determine exactly where space ends and begins, since with altitude the density of atmospheric gases gradually decreases and itself gradually turns into almost a vacuum, in which only individual molecules are found. As they move away from the earth's surface, atmospheric gases experience less and less gravity from the planet and, from a certain height, tend to leave the earth's gravitational field. Already at an altitude of approximately 320 km, the density of the atmosphere is so low that molecules can travel more than 1 km without colliding with each other. The outermost part of the atmosphere serves as its upper boundary, which is located at altitudes from 480 to 960 km.