Question 1. What determines the distribution of heat over the surface of the Earth?

The distribution of air temperature above the Earth's surface depends on the following four main factors: 1) latitude, 2) height of the land surface, 3) type of surface, especially the location of land and sea, 4) heat transfer by winds and currents.

Question 2. In what units is temperature measured?

In meteorology and in everyday life, the Celsius scale or degrees Celsius is used as a unit of temperature.

Question 3. What is the name of the temperature measuring device?

Thermometer - a device for measuring air temperature.

Question 4. How does the air temperature change during the day, during the year?

The change in temperature depends on the rotation of the Earth around its axis and, accordingly, on changes in the amount of solar heat. Therefore, the air temperature rises or falls depending on the location of the Sun in the sky. The change in air temperature during the year depends on the position of the Earth in its orbit as it revolves around the Sun. In summer, the earth's surface heats up well due to direct fall sun rays.

Question 5. Under what conditions at a particular point on the surface of the Earth will the air temperature always remain constant?

If the Earth does not rotate around the sun and its axis, and there will be no air transport by winds.

Question 6. According to what pattern does air temperature change with height?

When rising above the Earth's surface, the air temperature in the troposphere drops by 6 C for each kilometer of ascent.

Question 7. What is the relationship between air temperature and the geographical latitude of the place?

The amount of light and heat received by the earth's surface gradually decreases in the direction from the equator to the poles due to a change in the angle of incidence of the sun's rays.

Question 8. How and why does the air temperature change during the day?

The sun rises in the east, rises higher and higher, and then begins to sink until it sets below the horizon until the next morning. The daily rotation of the Earth causes the angle of incidence of the sun's rays on the Earth's surface to change. This means that the level of heating of this surface also changes. In turn, the air, which is heated from the Earth's surface, receives a different amount of heat during the day. And at night, the amount of heat received by the atmosphere is even less. This is the reason for the diurnal variability. During the day, the air temperature rises from dawn to two in the afternoon, and then begins to drop and reaches a minimum an hour before dawn.

Question 9. What is the temperature range?

The difference between the highest and lowest air temperature for any period of time is called the temperature amplitude.

Question 11. Why is the most heat observed at 14:00, and the lowest - in the "pre-dawn hour"?

Because at 14 o'clock the Sun heats the earth as much as possible, and in the pre-dawn hour the Sun has not yet risen, and during the night the temperature dropped all the time.

Question 12. Is it always possible to limit ourselves to knowledge only about average temperatures?

No, because in certain situations it is necessary to know the exact temperature.

Question 13. For what latitudes and why are the lowest average air temperatures typical?

For polar latitudes, since the sun's rays reach the surface at the smallest angle.

Question 14. For what latitudes and why are the highest average air temperatures typical?

The highest average air temperatures are typical for the tropics and the equator, since there is the largest angle of incidence of sunlight.

Question 15. Why does the air temperature decrease with height?

Because the air warms up from the surface of the Earth, when it has a positive temperature and it turns out that the higher the air layer, the less it warms up.

Question 16. What do you think, which month of the year is characterized by the minimum average air temperatures in the Northern Hemisphere? In the southern hemisphere?

January on average, the most cold month year in most of the Northern Hemisphere of the Earth, and the warmest month of the year in most of the Southern Hemisphere. June is, on average, the coldest month of the year in most of the Southern Hemisphere.

Question 17 latitude, 50°S sh., 80 p. sh.?

Question 18. Determine the air temperature at a height of 3 km, if it is +24 ° C at the Earth's surface?

tn=24-6.5*3=4.5 ºС

Question 19. Calculate the average temperature value according to the data presented in the table.

(5+0+3+4+7+10+5) : 6 = 4,86; (-3 + -1) : 2 = -2; 4,86 - 2 = 2,86

Answer: average temperature= 2.86 degrees.

Question 20. Using the tabular data given in task 2, determine the temperature amplitude for the specified period.

The temperature amplitude for the specified period will be 13 degrees.

Question 1. What determines the distribution of heat over the surface of the Earth?

The distribution of air temperature above the Earth's surface depends on the following four main factors: 1) latitude, 2) height of the land surface, 3) type of surface, especially the location of land and sea, 4) heat transfer by winds and currents.

Question 2. In what units is temperature measured?

In meteorology and in everyday life, the Celsius scale or degrees Celsius is used as a unit of temperature.

Question 3. What is the name of the temperature measuring device?

Thermometer - a device for measuring air temperature.

Question 4. How does the air temperature change during the day, during the year?

The change in temperature depends on the rotation of the Earth around its axis and, accordingly, on changes in the amount of solar heat. Therefore, the air temperature rises or falls depending on the location of the Sun in the sky. The change in air temperature during the year depends on the position of the Earth in its orbit as it revolves around the Sun. In summer, the earth's surface heats up well due to direct sunlight.

Question 5. Under what conditions at a particular point on the surface of the Earth will the air temperature always remain constant?

If the Earth does not rotate around the sun and its axis, and there will be no air transport by winds.

Question 6. According to what pattern does air temperature change with height?

When rising above the Earth's surface, the air temperature in the troposphere drops by 6 C for each kilometer of ascent.

Question 7. What is the relationship between air temperature and the geographical latitude of the place?

The amount of light and heat received by the earth's surface gradually decreases in the direction from the equator to the poles due to a change in the angle of incidence of the sun's rays.

Question 8. How and why does the air temperature change during the day?

The sun rises in the east, rises higher and higher, and then begins to sink until it sets below the horizon until the next morning. The daily rotation of the Earth causes the angle of incidence of the sun's rays on the Earth's surface to change. This means that the level of heating of this surface also changes. In turn, the air, which is heated from the Earth's surface, receives a different amount of heat during the day. And at night, the amount of heat received by the atmosphere is even less. This is the reason for the diurnal variability. During the day, the air temperature rises from dawn to two in the afternoon, and then begins to drop and reaches a minimum an hour before dawn.

Question 9. What is the temperature range?

The difference between the highest and lowest air temperature for any period of time is called the temperature amplitude.

Question 11. Why is the highest temperature observed at 2 p.m., and the lowest - in the "pre-dawn hour"?

Because at 14 o'clock the Sun heats the earth as much as possible, and in the pre-dawn hour the Sun has not yet risen, and during the night the temperature dropped all the time.

Question 12. Is it always possible to limit ourselves to knowledge only about average temperatures?

No, because in certain situations it is necessary to know the exact temperature.

Question 13. For what latitudes and why are the lowest average air temperatures typical?

For polar latitudes, since the sun's rays reach the surface at the smallest angle.

Question 14. For what latitudes and why are the highest average air temperatures typical?

The highest average air temperatures are typical for the tropics and the equator, since there is the largest angle of incidence of sunlight.

Question 15. Why does the air temperature decrease with height?

Because the air warms up from the surface of the Earth, when it has a positive temperature and it turns out that the higher the air layer, the less it warms up.

Question 16. What do you think, which month of the year is characterized by the minimum average air temperatures in the Northern Hemisphere? In the southern hemisphere?

January is, on average, the coldest month of the year in most of the Earth's Northern Hemisphere, and the warmest month of the year in most of the Southern Hemisphere. June is, on average, the coldest month of the year in most of the Southern Hemisphere.

Question 17 latitude, 50°S sh., 80 p. sh.?

Question 18. Determine the air temperature at a height of 3 km, if it is +24 ° C at the Earth's surface?

tn=24-6.5*3=4.5 ºС

Question 19. Calculate the average temperature value according to the data presented in the table.

(5+0+3+4+7+10+5) : 6 = 4,86; (-3 + -1) : 2 = -2; 4,86 - 2 = 2,86

Answer: average temperature = 2.86 degrees.

Question 20. Using the tabular data given in task 2, determine the temperature amplitude for the specified period.

The temperature amplitude for the specified period will be 13 degrees.

Blue planet...

This topic was supposed to appear on the site one of the first. After all, helicopters are atmospheric aircraft. Earth's atmosphere- their, so to speak, habitat :-). BUT physical properties air just determine the quality of this habitat :-). So that's one of the basics. And the basis is always written first. But I just realized this now. However, it is better, as you know, late than never ... Let's touch on this issue, but without getting into the wilds and unnecessary difficulties :-).

So… Earth's atmosphere. This is the gaseous shell of our blue planet. Everyone knows this name. Why blue? Simply because the “blue” (as well as blue and violet) component of sunlight (spectrum) is most well scattered in the atmosphere, thus coloring it in bluish-bluish, sometimes with a hint of violet (on a sunny day, of course :-)) .

Composition of the Earth's atmosphere.

The composition of the atmosphere is quite wide. I will not list all the components in the text, there is a good illustration for this. The composition of all these gases is almost constant, with the exception of carbon dioxide (CO 2 ). In addition, the atmosphere necessarily contains water in the form of vapors, suspended droplets or ice crystals. The amount of water is not constant and depends on temperature and, to a lesser extent, on air pressure. In addition, the Earth's atmosphere (especially the current one) also contains a certain amount, I would say "all sorts of filth" :-). These are SO 2, NH 3, CO, HCl, NO, in addition there are mercury vapors Hg. True, all this is there in small quantities, thank God :-).

Earth's atmosphere It is customary to divide into several zones following each other in height above the surface.

The first, closest to the earth, is the troposphere. This is the lowest and, so to speak, the main layer for life. different kind. It contains 80% of the total mass atmospheric air(although by volume it makes up only about 1% of the entire atmosphere) and about 90% of all atmospheric water. The bulk of all winds, clouds, rains and snows 🙂 come from there. The troposphere extends to heights of about 18 km in tropical latitudes and up to 10 km in polar latitudes. The air temperature in it drops with a rise of about 0.65º for every 100 m.

atmospheric zones.

The second zone is the stratosphere. I must say that another narrow zone is distinguished between the troposphere and stratosphere - the tropopause. It stops the temperature drop with height. The tropopause has an average thickness of 1.5-2 km, but its boundaries are indistinct and the troposphere often overlaps the stratosphere.

So the stratosphere has an average height of 12 km to 50 km. The temperature in it up to 25 km remains unchanged (about -57ºС), then somewhere up to 40 km it rises to about 0ºС and further up to 50 km it remains unchanged. The stratosphere is a relatively quiet part of the earth's atmosphere. Adverse weather it is practically absent. It is in the stratosphere that the famous ozone layer is located at altitudes from 15-20 km to 55-60 km.

This is followed by a small boundary layer stratopause, in which the temperature remains around 0ºС, and then the next zone is the mesosphere. It extends to altitudes of 80-90 km, and in it the temperature drops to about 80ºС. In the mesosphere, small meteors usually become visible, which begin to glow in it and burn out there.

The next narrow gap is the mesopause and beyond it the thermosphere zone. Its height is up to 700-800 km. Here the temperature again begins to rise and at altitudes of about 300 km it can reach values ​​of the order of 1200ºС. Thereafter, it remains constant. The ionosphere is located inside the thermosphere up to a height of about 400 km. Here, the air is strongly ionized due to exposure to solar radiation and has a high electrical conductivity.

The next and, in general, the last zone is the exosphere. This is the so-called scatter zone. Here, mainly very rarefied hydrogen and helium (with a predominance of hydrogen) are present. At altitudes of about 3000 km, the exosphere passes into the near space vacuum.

It's like that somewhere. Why about? Because these layers are rather conditional. Various changes in altitude, composition of gases, water, temperature, ionization, and so on are possible. In addition, there are many more terms that define the structure and state of the earth's atmosphere.

For example homosphere and heterosphere. In the first, the atmospheric gases are well mixed and their composition is quite homogeneous. The second is located above the first and there is practically no such mixing there. The gases are separated by gravity. The boundary between these layers is located at an altitude of 120 km, and it is called turbopause.

Let's finish with the terms, but I will definitely add that it is conventionally accepted that the boundary of the atmosphere is located at an altitude of 100 km above sea level. This border is called the Karman Line.

I will add two more pictures to illustrate the structure of the atmosphere. The first, however, is in German, but it is complete and easy enough to understand :-). It can be enlarged and well considered. The second shows the change in atmospheric temperature with altitude.

The structure of the Earth's atmosphere.

Change in air temperature with height.

Modern manned orbital spacecraft fly at altitudes of about 300-400 km. However, this is no longer aviation, although the area, of course, is in a certain sense closely related, and we will certainly talk about it again :-).

The aviation zone is the troposphere. Modern atmospheric aircraft can also fly in the lower layers of the stratosphere. For example, the practical ceiling of the MIG-25RB is 23000 m.

Flight in the stratosphere.

And exactly physical properties of air tropospheres determine how the flight will be, how effective the aircraft control system will be, how the turbulence in the atmosphere will affect it, how the engines will work.

The first main property is air temperature. In gas dynamics, it can be determined on the Celsius scale or on the Kelvin scale.

Temperature t1 at a given height H on the Celsius scale is determined:

t 1 \u003d t - 6.5N, where t is the air temperature at the ground.

Temperature on the Kelvin scale is called absolute temperature Zero on this scale is absolute zero. At absolute zero, the thermal motion of molecules stops. Absolute zero on the Kelvin scale corresponds to -273º on the Celsius scale.

Accordingly, the temperature T on high H on the Kelvin scale is determined:

T \u003d 273K + t - 6.5H

Air pressure. Atmosphere pressure measured in Pascals (N / m 2), in the old system of measurement in atmospheres (atm.). There is also such a thing as barometric pressure. This is the pressure measured in millimeters mercury column using a mercury barometer. Barometric pressure (pressure at sea level) equal to 760 mm Hg. Art. called standard. In physics, 1 atm. just equal to 760 mm Hg.

Air density. In aerodynamics, the most commonly used concept is the mass density of air. This is the mass of air in 1 m3 of volume. The density of air changes with height, the air becomes more rarefied.

Air humidity. Shows the amount of water in the air. There is a concept " relative humidity ". This is the ratio of the mass of water vapor to the maximum possible at a given temperature. The concept of 0%, that is, when the air is completely dry, can exist in general only in the laboratory. On the other hand, 100% humidity is quite real. This means that the air has absorbed all the water it could absorb. Something like an absolutely "full sponge". High relative humidity reduces air density, while low relative humidity increases it accordingly.

Due to the fact that aircraft flights take place under different atmospheric conditions, their flight and aerodynamic parameters in one flight mode may be different. Therefore, for a correct assessment of these parameters, we introduced International Standard Atmosphere (ISA). It shows the change in the state of the air with the rise in altitude.

The main parameters of the state of air at zero humidity are taken as:

pressure P = 760 mm Hg. Art. (101.3 kPa);

temperature t = +15°C (288 K);

mass density ρ \u003d 1.225 kg / m 3;

For the ISA, it is assumed (as mentioned above :-)) that the temperature drops in the troposphere by 0.65º for every 100 meters of altitude.

Standard atmosphere (example up to 10000 m).

ISA tables are used for calibrating instruments, as well as for navigational and engineering calculations.

Physical properties of air also include such concepts as inertness, viscosity and compressibility.

Inertia is a property of air that characterizes its ability to resist changes in the state of rest or uniform rectilinear motion. . The measure of inertia is the mass density of air. The higher it is, the higher the inertia and drag force of the medium when the aircraft moves in it.

Viscosity. Determines the frictional resistance against air as the aircraft moves.

Compressibility measures the change in air density as pressure changes. At low speeds of the aircraft (up to 450 km/h), there is no change in pressure when the air flow flows around it, but at high speeds, the effect of compressibility begins to appear. Its influence on supersonic is especially pronounced. This is a separate area of ​​​​aerodynamics and a topic for a separate article :-).

Well, it seems that's all for now ... It's time to finish this slightly tedious enumeration, which, however, cannot be dispensed with :-). Earth's atmosphere, its parameters, physical properties of air are as important for the aircraft as the parameters of the apparatus itself, and it was impossible not to mention them.

For now, until the next meetings and more interesting topics 🙂 …

P.S. For dessert, I suggest watching a video filmed from the cockpit of a MIG-25PU twin during its flight into the stratosphere. Filmed, apparently, by a tourist who has money for such flights :-). Filmed mostly through the windshield. Notice the color of the sky...

Every minute the Sun brings down on our planet a gigantic amount of light and heat. Why is the air temperature not always and everywhere the same?

How is the air heated?

The sun's rays pass through the air of the atmosphere, almost without heating it. The air receives the main heat from the earth's surface heated by the sun's rays. Therefore, the air temperature in the troposphere decreases by 0.6 ° C for every 100 meters of altitude.

The earth's surface and the air above it are heated unevenly by the sun. It depends on the angle of incidence of the sun's rays. The greater the angle of incidence of the sun's rays, the higher the air temperature. Therefore, over the poles, the air is colder than. The temperature fluctuations on Earth are very large: from +58.1 °С in to -89.2 °С in .

The heating of a surface, and hence the temperature of the air above it, also depends on the ability of the surface to absorb heat and reflect the sun's rays.

Change in air temperature

The air temperature at the same latitude is not constant. It changes during the day and seasons of the year following the change in the angle of incidence of the sun's rays. Daily changes are most distinct in clear, cloudless weather. Seasonal differences are most significant in illumination.

The annual course of air temperature is characterized by average monthly temperatures. In the countries of the Northern Hemisphere, the highest average monthly temperature usually in July, the lowest in January.

In the mountains, the air temperature drops with height. Therefore, the higher the mountains, the lower the temperature on the peaks.

The temperature also changes during the day. At any latitude clear weather in summer the highest temperature is at 2 pm and the lowest before sunrise. The difference between the highest (maximum) and lowest (minimum) temperatures for any period of time is called the temperature amplitude. Usually determine the daily and annual amplitude.

On the maps, points with equal temperatures are connected by lines - isotherms. As a rule, isotherms of average temperatures in January and July are shown.

Greenhouse effect

Observations have shown that since 1860 the average temperature at the Earth's surface has risen by 0.6 °C and continues to rise. Warming is associated with a phenomenon called the greenhouse effect. Its main culprit is carbon dioxide, which accumulates in the atmosphere as a result of fuel combustion. It poorly transmits heat from the heated earth's surface to the atmosphere, so the temperature rises in the surface layers of the troposphere. If the content of carbon dioxide in the atmosphere continues to grow, the Earth will experience very strong warming.

Air temperature change with altitude

The vertical distribution of temperature in the atmosphere is the basis for dividing the atmosphere into five main layers (see Section 1.3). For agricultural meteorology the greatest interest represent patterns of temperature changes in the troposphere, especially in its surface layer.

Vertical temperature gradient

The change in air temperature per 100 m of altitude is called the vertical temperature gradient (VTG).

The VGT depends on a number of factors: the season (it is less in winter, more in summer), the time of day (less at night, more during the day), the location of air masses (if at any heights above the cold air layer there is a layer of warmer air, then the VGT changes reverse sign). The average value of the VGT in the troposphere is about 0.6°C/100 m.

In the surface layer of the atmosphere, the VGT depends on the time of day, the weather, and the nature of the underlying surface. In the daytime, VGT is almost always positive, especially in summer over land, but in clear weather it is ten times greater than in cloudy weather. On a clear noon in summer, the air temperature near the soil surface can be 10 °C or more higher than the temperature at a height of 2 m. As a result, the WGT in this two-meter layer in terms of 100 m is more than 500°C/100 m. The wind reduces the WGT, since at When the air is mixed, its temperature at different heights is equalized. Reduce VGT cloudiness and precipitation. With moist soil, the WGT sharply decreases in the surface layer of the atmosphere. Above bare soil (fallow field), the VGT is greater than over a developed crop or meadow. In winter, above the snow cover, the VGT in the surface layer of the atmosphere is small and often negative.

With height, the influence of the underlying surface and weather on the VGT weakens and the VGT decreases compared to its value -

mi in the surface layer of air. Above 500 m, the influence of the diurnal variations in air temperature is attenuated. At altitudes from 1.5 to 5-6 km, the UGT is in the range of 0.5-0.6 ° С / 100 m. At an altitude of 6-9 km, the VGT increases and amounts to 0.65-0.75 ° С / 100 m. In the upper troposphere, the VGT again decreases to 0.5–0.2°C/100 m.

Data on VGT in various layers of the atmosphere are used in the preparation of weather forecasts, in meteorological services jet aircraft and when launching satellites into orbit, as well as when determining the conditions for the release and propagation industrial waste in the atmosphere. Negative VGT in the surface air layer at night in spring and autumn indicates the possibility of freezing.

4.3.2. Vertical air temperature distribution

The temperature distribution in the atmosphere with height is called atmospheric stratification. Its stability depends on the stratification of the atmosphere, i.e., the possibility of moving individual volumes of air in the vertical direction. Such movements of large volumes of air occur almost without heat exchange with the environment, i.e. adiabatically. This changes the pressure and temperature of the moving volume of air. If the volume of air moves up, then it goes into layers with less pressure and expands, as a result of which its temperature decreases. When the air is lowered, the reverse process occurs.

The change in temperature of air unsaturated with steam (see section 5.1) is 0.98°C for adiabatic vertical movement of 100 m (practically 1.0°C/100 m). When VGT< 1,0° С/100 м, то поднимающийся под влиянием внешнего им­пульса объем воздуха при охлаждении на 1°С на высоте 100 м будет холоднее окружающего воздуха и как более плотный нач­нет опускаться в исходное положение. Такое состояние атмосферы характеризует stable balance.

At VGT =.1.0 ° C / 100 m, the temperature of the rising volume of air at all heights will be equal to the ambient air temperature. Therefore, a volume of air artificially raised to a certain height and then left to itself will neither rise nor fall further. This state of the atmosphere is called indifferent.

If VGT> 1.0 ° C / 100 m, then the rising volume of air, cooling only by 1.0 ° C for every 100 m, turns out to be warmer at all heights environment, and therefore the resulting vertical movement continues. Created in the atmosphere unstable balance. Such a state occurs when the underlying surface is strongly heated, when the VGT increases with height. This contributes to the further development of convection, which

extends approximately to the height at which the temperature of the rising air becomes equal to the ambient temperature. With great instability, powerful cumulonimbus clouds arise, from which showers and hail are dangerous for crops.

AT temperate latitudes of the northern hemisphere, the temperature at the upper boundary of the troposphere, i.e., at an altitude of about 10-12 km, is about -50 ° C throughout the year. At an altitude of 5 km, it changes in July from -4 ° C (by 40 ° C . w.) to -12 ° C (at 60 ° N), and in January at the same latitudes and the same height it is -20 and -34 ° C, respectively (Table 20). In an even lower (boundary) layer of the troposphere, the temperature varies even more depending on the geographical latitude, season, and the nature of the underlying surface.

Table 20

The average distribution of air temperature (°C) in height in the troposphere in January and July over 40 and 60°N.

Air temperature regime

Height, km

For Agriculture The most important is the temperature regime of the lower part of the surface layer of the atmosphere, up to about a height of 2 m, where the majority of cultivated plants and farm animals live. In this layer, the vertical gradients of almost all meteorological quantities are very high; are large compared to other layers. As already mentioned, the VGT in the surface layer of the atmosphere is usually< много раз превышает ВП в остальной тропосфере В ясные тихие дни, когд< турбулентное перемешива

23 °С

Rice. 18. Temperature distribution in the surface layer of air and in the arable layer of soil during the day (1) and at night (2).

weakened, the difference in air temperatures at

soil surface and at a height of 2 m can exceed 10 ° C. On clear, quiet nights, the air temperature rises to a certain height (inversion) and the VGT becomes negative.

Consequently, there are two types of temperature distribution along the vertical in the surface layer of the atmosphere. The type at which the temperature of the soil surface is greatest, and leaves the surface both up and down, is called insolation. It is observed during the day when the soil surface is heated by direct solar radiation. The inverse temperature distribution is called radiation type, or type radiation(Fig. 18). This type is usually observed at night, when the surface is cooled as a result of effective radiation and the adjacent layers of air are cooled from it.