Due to the shielding effect, it prevents both the cooling of the Earth's surface due to its own thermal radiation and its heating by the radiation of the Sun, thereby reducing seasonal and daily fluctuations in air temperature.
Cloudiness characteristics
Number of clouds
The amount of clouds is the degree of coverage of the sky with clouds (at a certain moment or on average over a certain period of time), expressed in a 10-point scale or as a percentage of coverage. The modern 10-point cloudiness scale was adopted at the first Maritime International Meteorological Conference (Brussels, city).
When observing at meteorological stations, the total amount of clouds and the amount of low-tier clouds are determined; these numbers are recorded in the weather diaries with a fractional bar, for example 10/4 .
In aviation meteorology, an 8-octant scale is used, which is easier for visual observation: the sky is divided into 8 parts (that is, in half, then in half, and again), cloudiness is indicated in octants (eighths of the sky). In aeronautical meteorological weather reports (METAR, SPECI, TAF), the amount of clouds and the height of the lower boundary are indicated by layers (from the lowest to the highest), using the gradations of the amount:
- FEW - insignificant (scattered) - 1-2 octants (1-3 points);
- SCT - scattered (separate) - 3-4 octants (4-5 points);
- BKN - significant (broken) - 5-7 octants (6-9 points);
- OVC - solid - 8 octants (10 points);
- SKC - clear - 0 points (0 octants);
- NSC - no significant cloud cover (any amount of clouds with a lower boundary height of 1500 m and above, in the absence of cumulonimbus and power-cumulus clouds);
- CLR - no clouds below 3000 m (abbreviation used in reports generated by automatic weather stations).
Cloud shapes
Observed cloud shapes (in Latin designations) are indicated in accordance with the international cloud classification.
Cloud base height (VNGO)
Determined by the VNGO of the lower tier in meters. At a number of meteorological stations (especially aviation), this parameter is measured by a device (error 10-15%), at the rest - visually, approximately (in this case, the error can reach 50-100%; visual VNGO is the most unreliable weather element). Depending on the VNGO, cloudiness can be divided into 3 tiers (Lower, Middle and Upper). The lower tier includes (approximately up to a height of 2 km): stratus (precipitation may fall in the form of drizzle), stratified rain (heavy precipitation), stratified-cumulus (in aviation meteorology, there are also ruptured-stratus and broken-rain) clouds. Middle tier (about 2 km to 4-6 km): Altostratus and Altocumulus. Upper tier: cirrus, cirrocumulus, cirrostratus.
The height of the top of the clouds
It can be determined based on the data of airborne and radar sounding of the atmosphere. At meteorological stations, it is usually not measured, but in aviation forecasts for routes and areas of flight, the expected (forecasted) height of the cloud top is indicated.
see also
Sources of
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Cloudy excerpt
Finally, the headman Dron entered the room and, bowing low to the princess, stopped at the lintel.Princess Marya walked across the room and stopped opposite him.
“Dronushka,” said Princess Marya, who saw in him an undoubted friend, the same Dronushka who, from his annual trip to the fair in Vyazma, brought her every time and served his special gingerbread with a smile. “Dronushka, now, after our misfortune,” she began and fell silent, unable to speak further.
“We all walk under God,” he said with a sigh. They were silent.
- Dronushka, Alpatych has gone somewhere, I have no one to turn to. Are they telling me the truth that I can't even leave?
- Why don't you go, Your Excellency, you can go, - said Dron.
- I was told that it is dangerous from the enemy. Darling, I can’t do anything, I don’t understand anything, there’s no one with me. I definitely want to go at night or early tomorrow morning. - The drone was silent. He glanced from under his brows at Princess Marya.
- There are no horses, - he said, - I told Yakov Alpatych.
- Why not? - said the princess.
- All from God's punishment, - said Dron. - Which horses were dismantled for the troops, and which died, what year. Not to feed the horses, but not to die of hunger ourselves! And so they don't eat for three days. There is nothing, completely ruined.
Princess Marya listened attentively to what he said to her.
- Are the peasants ruined? Do they have no bread? She asked.
- They die of hunger, - said Dron, - not like carts ...
- Why didn't you say, Dronushka? Can't you help? I will do everything I can ... - It was strange for Princess Marya to think that now, at such a moment, when such grief filled her soul, there could be people rich and poor, and that the rich could not help the poor. She vaguely knew and heard that there is a master's bread and that it is given to peasants. She also knew that neither her brother nor her father would refuse the peasants in need; she was only afraid to make a mistake in her words about this distribution of bread to the peasants, which she wanted to dispose of. She was glad that she was presented with an excuse for caring, one for which she was not ashamed to forget her grief. She began to ask Dronushka for details about the needs of the peasants and about what is the master's in Bogucharov.
- We have the master's bread, brother? She asked.
- The Lord's bread is all intact, - said Dron proudly, - our prince did not order to sell.
“Give him out to the peasants, give him out everything they need: I give you permission in the name of your brother,” said Princess Marya.
The drone said nothing and took a deep breath.
“Give them this bread, if it’s enough for them.” Distribute everything. I command you in the name of your brother, and tell them: what is ours, so is theirs. We will spare nothing for them. So tell me.
The drone gazed at the princess as she spoke.
- Fire me, mother, for God's sake, tell me to take the keys, - he said. - He served twenty-three years, did not do anything bad; dismiss, for God's sake.
Princess Marya did not understand what he wanted from her and from what he asked to fire himself. She answered him that she never doubted his devotion and that she was ready to do everything for him and for the men.
An hour after this, Dunyasha came to the princess with the news that Dron had come and all the peasants, by order of the princess, gathered at the barn, wanting to talk with the mistress.
- Yes, I never called them, - said Princess Marya, - I just told Dronushka to give them bread.
- Only for God's sake, princess mother, order them to drive away and do not go to them. All the deception is the same, - said Dunyasha, - and Yakov Alpatych will come, and we will go ... and you will not please ...
Cloudiness is determined visually using a 10-point system. If the sky is cloudless or there is one or more small clouds on it, occupying less than one tenth of the entire sky, then the cloudiness is considered equal to 0 points. With a cloud cover of 10 points, the whole sky is covered with clouds. If clouds cover 1/10, 2/10, or 3/10 parts of the sky, then the cloudiness is considered equal to 1, 2, or 3 points, respectively.
Determination of light intensity and background radiation level *
Photometers are used to measure illumination. Illumination in lux is determined by the deflection of the galvanometer needle. You can use photoexposure meters.
To measure the level of background radiation and radioactive contamination, dosimeters-radiometers (Bella, EKO, IRD-02B1, etc.) are used. Typically, these devices have two modes of operation:
1) assessment of the background radiation by the value of the equivalent dose rate of gamma radiation (μSv / h), as well as the pollution by gamma radiation of samples of water, soil, food, crop products, livestock, etc .;
* Units of measurement of radioactivity
Radionuclide activity (A)- a decrease in the number of radionuclide nuclei for a certain
time interval:
[A] = 1 Ki = 3.7 · 1010 dis / s = 3.7 · 1010 Bq.
Absorbed radiation dose (D) is the energy of ionizing radiation transferred to a certain mass of the irradiated substance:
[D] = 1 Gr = 1 J / kg = 100 rad.
Equivalent radiation dose (N) is equal to the product of the absorbed dose by
the average quality factor of ionizing radiation (K), taking into account biological
the genetic effect of various radiation on biological tissue:
[N] = 1 Sv = 100 rem.
Exposure dose (X) is a measure of the ionizing effect of radiation, which is
which is equal to 1 Ku / kg or 1 P:
1 P = 2.58 10-4 Ku / kg = 0.88 rad.
The dose rate (exposure, absorbed, or equivalent) is the ratio of the dose increment over a certain time interval to the value of this time interval:
1 Sv / s = 100 R / s = 100 rem / s.
2) assessment of the degree of contamination with beta, gamma - emitting radionuclides of surfaces and samples of soil, food, etc. (particles / min · cm2 or kBq / kg).
The maximum permissible radiation dose is 5 mSv / year.
Determination of the level of radiation safety
Determination of the level of radiation safety is carried out on the example of using a household dosimeter-radiometer (IRD-02B1):
1. Set the operating mode switch to the "μSv / h" position.
2. Turn on the device, for which set the switch "off-on."
v position "on". Approximately 60 seconds after switching on, the device is ready
to work.
3. Place the device in the place where the equivalent dose rate is determined gamma radiation. After 25-30 seconds, the digital display will display a value that corresponds to the dose rate of gamma radiation in a given place, expressed in microsieverts per hour (μSv / h).
4. For a more accurate estimate, it is necessary to take the average of 3-5 consecutive readings.
The reading on the digital display of the device 0.14 means that the dose rate is 0.14 μSv / h or 14 μR / h (1 Sv = 100 R).
After 25-30 seconds after the start of the device, it is necessary to take three consecutive readings and find the average value. The results are presented in the form of a table. 2.
Table 2. Determination of radiation level
Instrument readings |
Mean |
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dose rate |
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Registration of the results of microclimatic observations
The data of all microclimatic observations are recorded in a notebook, and then processed and drawn up in the form of a table. 3.
Table 3. Results of processing microclimatic
observations
Temperature |
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air ra |
Temperature |
Humidity |
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on high, |
air ra, |
air on |
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height,% |
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d) 680 mm Hg. Art. 2. Average monthly temperatures are calculated: a) by the sum of average daily temperatures; b) dividing the sum of average daily temperatures by the number of days in a month; c) from the difference in the sum of temperatures of the previous and next months. 3. Set the correspondence: pressure indicators a) 760 mm Hg. Art .; 1) below the norm; b) 732 mm Hg. Art .; 2) normal; c) 832 mm Hg. Art. 3) above the norm. 4. The reason for the uneven distribution of sunlight over the earth's surface is: a) distance from the sun; b) the sphericity of the Earth; c) a thick layer of the atmosphere. 5. The daily amplitude is: a) the total number of temperature indicators during the day; b) the difference between the highest and lowest air temperature indicators during the day; c) the course of temperatures during the day. 6. What device is used to measure atmospheric pressure: a) hygrometer; b) a barometer; c) rulers; d) thermometer. 7. The sun is at its zenith at the equator: a) December 22; b) September 23; c) October 23; d) September 1. 8. The layer of the atmosphere where all weather phenomena occur: a) stratosphere; b) troposphere; c) ozone; d) the mesosphere. 9. The layer of the atmosphere that does not transmit ultraviolet rays: a) the troposphere; b) ozone; c) stratosphere; d) the mesosphere. 10. At what time in summer with clear weather the lowest air temperature is observed: a) at midnight; b) before sunrise; c) after sunset. 11. Calculate the blood pressure of Mount Elbrus. (Find the height of the peaks on the map, take the BP at the foot of the mountain conditionally as 760 mm Hg.) 12. At an altitude of 3 km, the air temperature = - 15 ‘C, which is equal to the air temperature at the Earth’s surface: a) + 5’C; b) + 3'C; c) 0'C; d) -4'C.
Option 1 Set the correspondence: pressure indicators a) 749 mm Hg;1) below normal;
b) 760 mm Hg; 2) normal;
c) 860 mm Hg; 3) above the norm.
The difference between the highest and lowest air temperature values
called:
a) pressure; b) air movement; c) amplitude; d) condensation.
3. The reason for the uneven distribution of solar heat on the surface of the Earth
is an:
a) distance from the sun; b) sphericity;
c) different thickness of the atmospheric layer;
4. Atmospheric pressure depends on:
a) wind strength; b) wind direction; c) air temperature differences;
d) relief features.
The sun is at its zenith at the equator:
The ozone layer is located in:
a) troposphere; b) the stratosphere; c) the mesosphere; d) exosphere; e) thermosphere.
Fill in the pass: the air envelope of the earth is - _________________
8. Where is the lowest tropospheric thickness:
a) at the poles; b) in temperate latitudes; c) at the equator.
Arrange the heating steps in the correct sequence:
a) heating the air; b) the sun's rays; c) heating of the earth's surface.
What time in summer, with clear weather, is the highest temperature
air: a) at noon; b) before noon; c) in the afternoon.
10. Fill in the pass: when climbing the mountains, atmospheric pressure ..., for each
10.5 m at… .mm Hg
Calculate the atmospheric pressure in Narodnaya. (Find the height of the peaks on
map, blood pressure at the foot of the mountains, take conditionally for 760 mm Hg)
During the day, the following data were recorded:
max t = + 2'C, min t = -8'C; Determine the amplitude and average daily temperature.
Option 2
1. At the foot of the mountain, blood pressure is 760 mm Hg. What will be the pressure at an altitude of 800 m:
a) 840 mm Hg. Art .; b) 760 mm Hg. Art .; c) 700 mm Hg. Art .; d) 680 mm Hg. Art.
2. Average monthly temperatures are calculated:
a) by the sum of average daily temperatures;
b) dividing the sum of average daily temperatures by the number of days in a month;
c) from the difference in the sum of temperatures of the previous and next months.
3. Set the correspondence:
pressure indicators
a) 760 mm Hg. Art .; 1) below normal;
b) 732 mm Hg. Art .; 2) normal;
c) 832 mm Hg. Art. 3) above the norm.
4. The reason for the uneven distribution of sunlight over the earth's surface
is: a) remoteness from the Sun; b) the sphericity of the Earth;
c) a thick layer of the atmosphere.
5. The daily amplitude is:
a) the total number of temperature indicators during the day;
b) the difference between the highest and lowest air temperature indicators in
during the day;
c) the course of temperatures during the day.
6.With which device is the atmospheric pressure measured:
a) a hygrometer; b) a barometer; c) rulers; d) thermometer.
7. The sun is at its zenith at the equator:
2) what can be depicted on the terrain plan?
and the school site
b ocean
to the Crimean peninsula
mainland
3) which of the listed objects are indicated on the terrain plan by linear signs?
and rivers, lakes
b borders, communication routes
to settlements, mountain peaks
g minerals, forests
4) within what limits is the geographic latitude measured?
a 0-180 "
b 0-90 "
at 0-360 "
g 90-180 "
Cloudiness- a complex of clouds, manifested in a certain place on the planet (targeted point or territory) at a certain moment or period of time.
Cloud types
This or that kind of cloudiness corresponds to certain processes taking place in the atmosphere, and therefore foreshadows this or that weather. Knowledge of the types of clouds from the point of view of the skipper is important for predicting the weather from local signs. For practical purposes, clouds are subdivided into 10 basic shapes, which in turn are subdivided into 4 types in height and vertical extent:
Clouds of great vertical development. These include:
Cumulus Latin name - Cumulus(Cu is indicated on weather maps)- separate thick vertically developed clouds. The upper part of the cloud is domed with prominences, the lower part is almost horizontal. The average vertical length of the cloud is 0.5-2 km. The average height of the lower base from the earth's surface is 1.2 km.
- heavy masses of clouds of great vertical development in the form of towers and mountains. The upper part is a fibrous structure, often with lateral outliers in the form of an anvil. The average vertical length is 2-3 km. The average height of the lower base is 1 km. They often give heavy rainfall accompanied by thunderstorms.
Low clouds. These include:
- low, amorphous, stratified, almost uniform rain clouds of dark gray color. The lower base is 1-1.5 km. The average vertical length of the cloud is 2 km. Heavy precipitation falls out of such clouds.
- a uniform light gray fog-like shroud of continuous low clouds. Often formed from raised fog or faded into fog. The height of the lower base is 0.4 - 0.6 km. Average vertical length - 0.7 km.
- Low cloud cover, consisting of individual ridges, waves, plates or flakes, separated by gaps or translucent areas (translucent) or without clearly visible gaps, the fibrous structure of such clouds is more clearly visible at the horizon.
Middle clouds. These include:
- a fibrous veil of gray or bluish color. The lower base is located at an altitude of 3 - 5 km. Vertical length - 04 - 0.8 km).
- layers or spots, consisting of strongly flattened rounded masses. The lower base is located at an altitude of 2 - 5 km. The average vertical length of the cloud is 0.5 km.
Clouds of the upper tier. All of them are white; during the day they almost do not give a shadow. These include:
Cirrostratus (Cs) - a thin whitish translucent veil, gradually covering the entire sky. They do not obscure the outer contours of the Sun and Moon, leading to the appearance of a halo around them. The lower border of the cloud is at an altitude of about 7 km.
According to the international classification, there are 10 main types of clouds of different tiers.
> TOP CLOUDS(h> 6km) 
Spindrift clouds(Cirrus, Ci) - These are individual clouds of fibrous structure and a whitish hue. Sometimes they have a very regular structure in the form of parallel threads or stripes, sometimes on the contrary, the fibers are tangled and scattered across the sky in separate spots. Cirrus clouds are transparent, as they consist of the smallest ice crystals. Often the appearance of such clouds foreshadows a change in the weather. Cirrus clouds are sometimes difficult to distinguish from satellites.
Cirrocumulus clouds(Cirrocumulus, Cc) - a layer of clouds, thin and translucent, like cirrus, but consisting of separate flakes or small balls, and sometimes, as it were, of parallel waves. These clouds usually form, figuratively speaking, a "cumulus" sky. They often appear together with cirrus clouds. Visible before storms.
Cirrostratus clouds(Cirrostratus, Cs) - a thin, translucent, whitish or milky cover through which the disk of the Sun or Moon is clearly visible. This cover can be uniform, like a layer of fog, or fibrous. On cirrostratus clouds, a characteristic optical phenomenon is observed - a halo (light circles around the Moon or the Sun, a false Sun, etc.). Like cirrus, cirrostratus clouds often indicate the approach of inclement weather.
> MIDDLE CLOUDS(h = 2-6 km)
They differ from similar cloud forms of the lower tier by their greater height, lower density, and a higher probability of the presence of an ice phase. 
Altocumulus clouds(Altocumulus, Ac) - A layer of white or gray clouds, consisting of ridges or separate "blocks", between which the sky usually shines through. The ridges and "lumps" that form the "feathery" palate are relatively thin and are arranged in regular rows or in a checkerboard pattern, less often in disorder. A "feathery" sky is usually a sign of rather bad weather.
Altostratus clouds(Altostratus, As) - a thin, less often dense veil of a grayish or bluish tint, in places heterogeneous or even fibrous in the form of white or gray patches throughout the palate. The sun or the moon shines through it in the form of light spots, sometimes rather faint. These clouds are a sure sign of a little rain.
> LOWER CLOUDS(h In the opinion of many scientists, stratus clouds are not logically assigned to the lower tier, since only their bases are located in this tier, and the tops reach heights of several kilometers (middle cloud levels). These heights are more characteristic of clouds of vertical development, and therefore, some scientists classify them as middle tier clouds.
Stratocumulus clouds(Stratocumulus, Sc) - cloudy layer, consisting of ridges, shafts or their individual elements, large and dense, gray. There are almost always darker areas.
The word "cumulus" (from the Latin "heap", "pile") means the tightness, heap of clouds. These clouds rarely bring rain, only sometimes they turn into stratus rain, from which rain or snow falls.
Stratus clouds(Stratus, St) - a rather uniform layer of low clouds of gray color, devoid of regular structure, very similar to fog that has risen over a hundred meters over the ground. Stratus clouds cover large areas and look like ragged patches. In winter, these clouds are often held all day, precipitation from them usually does not fall on the ground, sometimes there is drizzle. In the summer they quickly dissipate, after which the weather is good.
Stratus clouds(Nimbostratus, Ns, Frnb) are dark gray clouds, sometimes threatening. Often below their layer, low dark fragments of torn rain clouds appear - typical harbingers of rain or snow.
> VERTICAL DEVELOPMENT CLOUDS
Cumulus clouds (Cumulus, Cu)- dense, sharply outlined, with a flat, relatively dark base and a domed white, as if swirling, top, reminiscent of cauliflower. They begin as small white scraps, but soon they form a horizontal base, and the cloud begins to rise imperceptibly. With low humidity and a weak vertical ascent of air masses, cumulus clouds portend clear weather. Otherwise, they accumulate throughout the day and can cause thunderstorms.
Cumulonimbus (Cumulonimbus, Cb)- powerful cloud masses with a strong vertical development (up to a height of 14 kilometers), giving abundant rainfall with thunderstorms. They develop from cumulus clouds, differing from them in the upper part, consisting of ice crystals. A squally wind, heavy precipitation, thunderstorms, hail are associated with these clouds. The life span of these clouds is short - up to four hours. The base of the clouds is dark in color, and the white top extends far upward. In the warm season, the summit can reach the tropopause, and in the cold season, when convection is suppressed, the clouds are flatter. Clouds usually do not form a continuous cover. When a cold front passes, cumulonimbus clouds can form a ridge. The sun does not shine through cumulonimbus clouds. Cumulonimbus clouds form when the air mass is unstable, when there is an active upward movement of air. These clouds also often form on a cold front when cold air hits a warm surface.
Each cloud genus, in turn, is subdivided into species according to their shape and internal structure, for example, fibratus (fibrous), uncinus (claw-like), spissatus (dense), castellanus (tower-like), floccus (flocculent), stratiformis (layered ), nebulosus (foggy), lenticularis (lenticular), fractus (ruptured), humulus (flat), mediocris (medium), congestus (powerful), calvus (bald), capillatus (hairy). The types of clouds, further, have varieties, for example, vertebratus (ridged), undulatus (wavy), translucidus (translucent), opacus (opaque), etc. Further, additional features of clouds are distinguished, such as incus (anvil), mamma (uterus) , vigra (stripes of fall), tuba (trunk), etc. And, finally, evolutionary features indicating the origin of clouds are noted, for example, Cirrocumulogenitus, Altostratogenitus, etc.
Observing cloudiness, it is important to determine by eye on a ten-point scale the degree of sky coverage. Clear sky - 0 points. Clearly, there are no clouds in the sky. If it is covered with clouds no more than the warmth of the firmament 3 points, little cloudy. Cloudy, clearing 4 points. This means that the clouds cover half of the firmament, but at times their number decreases to "clear". When the sky is half closed, the cloudiness is 5 points. If they say "sky with gaps", they mean that the cloudiness is not less than 5, but not more than 9 points. Overcast - the sky is completely covered with clouds of a single blue skylight. Cloudiness 10 points.
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