What is the maximum number of points for clouds. Cloudiness
As you know, many of the industries, agriculture, transport services are very dependent on the efficiency, timeliness and reliability of the forecasts of the Federal Meteorological Service. Early warning of dangerous and especially hazards weather, the timeliness of storm warnings are all necessary conditions for the successful and safe operation of many sectors of the economy and transport. For example, long-term meteorological forecasts play a decisive role in the organization of agricultural production.
One of the most important parameters that determine the possibility of predicting hazardous weather conditions, is such an indicator as the height of the lower boundary of the clouds.
In meteorology, cloud height is the height of the cloud base above the earth's surface.
To understand the importance of conducting research to determine the height of clouds, it is worth mentioning the fact that clouds can be of different types. For various types clouds, the height of their lower boundary can vary within certain limits, and the average value of the height of the clouds is revealed.
So clouds can be:
stratus clouds ( average height 623 m.)
Rain clouds (average height 1527 m.)
Cumulus (top) (1855)
Cumulus (base) (1386)
Thunderstorm (top) (average height 2848 m.)
Thunderstorm (base) (average height 1405 m.)
False pinnate (average height 3897 m.)
Stratocumulus (average height 2331 m.)
High cumulus (below 4000 m) (average height 2771 m)
High cumulus (above 4000 m) (average height 5586 m)
Cirrocumulus (average height 6465 m)
Low cirrostratified (average height 5198 m.)
High cirrocumulus (average height 9254 m.)
Cirrus (average height 8878 m.)
As a rule, the height of the clouds of the lower and middle tiers is measured, not exceeding 2500 m. At the same time, the height of the lowest clouds from their entire array is determined. In fog, the height of the clouds is considered to be zero, and, in this case, “vertical visibility” is measured at airports.
To determine the height of the lower boundary of the clouds, the method of light location is used. In Russia, a meter is produced for these purposes, in which a flash lamp is used as a source of pulses and light.
The height of the lower boundary of the clouds by the method of light location using DVO-2 is determined by measuring the time it takes for a light pulse to travel from the light emitter to the cloud and back, as well as converting the obtained time value into a value of cloud height proportional to it. Thus, a light pulse is sent by the emitter and, after reflection, is received by the receiver. In this case, the emitter and receiver must be located in close proximity to each other.
Structurally, the DVO-2 meter is a complex of several separate devices:
transmitter and receiver,
communication lines,
measuring block,
Remote control.
The DVO-2 cloud height meter can operate autonomously with a measuring unit, complete with a remote control and as part of automated meteorological stations.
The transmitter consists of a flash tube, capacitors feeding it and a parabolic reflector. The reflector, together with the lamp and capacitors, is installed in a gimbal suspension enclosed in a housing with an opening lid.
The receiver consists of a parabolic mirror, a photodetector, a photoamplifier, also installed in a gimbal suspension and located in a housing with an opening lid.
The transmitter and receiver should be located near the main observation point. On runways, the transmitter and receiver are located at the nearest locator beacons at both ends of the runway.
The measuring unit, intended for collecting and processing information, consists of a measuring board, a high-voltage unit and a power supply unit.
The remote control includes a keyboard and indication board and a control board.
The signal from the receiver is transmitted via a two-wire potentially isolated communication line with unipolar signals and a rated current (20 ± 5) mA to the measuring unit, and from there to the remote control. Depending on the configuration, instead of a remote control for processing and displaying on the operator's display, the signal can be transmitted to the central system of the weather station.
The DVO-2 cloud height meter can operate either continuously or as needed. The remote control has a serial RS-232 interface designed to work with a computer. Information from DVO-2 meters can be transmitted over a communication line at a distance of up to 8 km.
Processing of measurement results on the measuring unit DVO-2 includes:
Averaging results over 8 measured values;
Exclusion from the number of measurements of those results in which there is a short-term loss of the reflected signal. Those. exclusion of the "gap in the clouds" factor;
Issuing a signal about the "absence of clouds" in the event that among the 15 observations made, 8 significant ones are not recruited;
Exclusion of the so-called locals - false reflection signals.
Cloudiness is determined visually using a 10-point system. If the sky is cloudless or there are one or more small clouds occupying less than one tenth of the entire sky, then the cloudiness is considered to be 0 points. With cloudiness equal to 10 points, the entire sky is covered with clouds. If 1/10, 2/10, or 3/10 of the sky is covered by clouds, then the cloudiness is considered equal to 1, 2, or 3 points, respectively.
Determination of light intensity and background radiation*
Photometers are used to measure illumination. The deviation of the galvanometer pointer determines the illumination in lux. Photometers can be used.
To measure the level of radiation background and radioactive contamination, dosimeters-radiometers ("Bella", "ECO", IRD-02B1, etc.) are used. Typically, these devices have two modes of operation:
1) assessment of the radiation background by the magnitude of the equivalent dose of gamma radiation (μSv/h), as well as contamination by gamma radiation of samples of water, soil, food, crop products, animal husbandry, etc.;
* Units of measurement of radioactivity
Radionuclide activity (А)- decrease in the number of radionuclide nuclei for a certain
fixed time interval:
[A] \u003d 1 Ci \u003d 3.7 1010 dispersal / s \u003d 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 Gy = 1 J/kg = 100 rad.
Equivalent radiation dose (N) is equal to the product of the absorbed dose by
average quality factor of ionizing radiation (K), taking into account biological
logical effect of various radiations on biological tissue:
[N] = 1 Sv = 100 rem.
Exposure dose (X) is a measure of the ionizing effect of radiation, a single
which is equal to 1 Ku/kg or 1 P:
1 P \u003d 2.58 10-4 Ku / kg \u003d 0.88 rad.
Dose rate (exposure, absorbed or equivalent) is the ratio of the dose increment for 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-radiating radionuclides of surfaces and samples of soil, food, etc. (particles / min. cm2 or kBq / kg).
The maximum allowable exposure dose is 5 mSv/year.
Determining the level of radiation safety
Level detection radiation safety is carried out on the example of using a household dosimeter-radiometer (IRD-02B1):
1. Set the operation mode switch to the "µSv/h" position.
2. Turn on the device, for which set the switch "off - on."
V "on" position. 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 indication 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 operation 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. Determining the level of radiation
Instrument readings |
Average value |
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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 presented in the form of a table. 3.
Table 3. Results of processing microclimatic
observations
Temperature- |
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ra air |
Temperature- |
Humidity |
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on high, |
ra air, |
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 subsequent 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. Cause of uneven distribution sunlight on the earth's surface is: a) distance from the Sun; b) the sphericity of the Earth; c) a powerful layer of the atmosphere. 5. Daily amplitude is: a) the total number of temperature indicators during the day; b) the difference between the highest and lowest air temperatures during the day; c) temperature change during the day. 6. What device is used to measure Atmosphere pressure: a) hygrometer; b) barometer; c) rulers; d) a thermometer. 7. The sun is at its zenith at the equator: a) December 22; b) September 23; c) October 23; d) September 1st. 8. The layer of the atmosphere where everything happens weather conditions: a) stratosphere; b) troposphere; c) ozone; d) mesosphere. 9. The layer of the atmosphere that does not transmit ultraviolet rays: a) the troposphere; b) ozone; c) stratosphere; d) mesosphere. 10. At what time in summer in clear weather is the lowest air temperature 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 a height 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 the norm;
b) 760 mm Hg; 2) normal;
c) 860 mm Hg; 3) above the norm.
Difference between the highest and lowest air temperatures
called:
a) pressure; b) air movement; c) amplitude; d) condensation.
3. The reason for the uneven distribution of solar heat on the Earth's surface
is:
a) distance from the sun b) sphericity;
c) different thicknesses of the atmospheric layer;
4. Atmospheric pressure depends on:
a) the force of the wind b) wind direction; c) air temperature difference;
d) relief features.
The sun is at its zenith at the equator:
The ozone layer is located in:
a) the troposphere; b) the stratosphere; c) mesosphere; d) exosphere; e) thermosphere.
Fill in the gap: the air shell of the earth is - _________________
8. Where is the least power of the troposphere observed:
a) at the poles; b) in temperate latitudes; c) at the equator.
Arrange the heating stages in correct sequence:
a) air heating; b) Sun rays; c) heating of the earth's surface.
At what time in the summer, when the weather is clear, is the highest temperature observed
air: a) at noon; b) before noon; c) after noon.
10. Fill in the gap: when climbing mountains, atmospheric pressure ..., for every
10.5 m per .... mm Hg
Calculate the atmospheric pressure in Narodnaya. (Find the height of the peaks on
map, take BP at the foot of the mountains conditionally for 760 mm Hg)
During the day, the following data was 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 subsequent months.
3. Match:
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 powerful layer of the atmosphere.
5. Daily amplitude is:
a) the total number of temperature indicators during the day;
b) the difference between the highest and lowest air temperatures in
during the day;
c) temperature change during the day.
6. What instrument is used to measure atmospheric pressure:
a) a hygrometer; b) barometer; c) rulers; d) a thermometer.
7. The sun is at its zenith at the equator:
2) What can be shown on the map?
and the school area
b ocean
V Crimean peninsula
g mainland
3) which of the listed objects are indicated on the terrain plan by linear signs?
and rivers, lakes
b borders, ways of communication
V settlements, mountain peaks
d minerals, forests
4) in what limits is the geographical latitude measured?
a 0-180"
b 0-90"
in 0-360"
g 90-180"
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 solar radiation, thereby reducing seasonal and daily fluctuations in air temperature.
Cloud Characteristics
Number of clouds
The amount of clouds is the degree of cloud coverage of the sky (at a certain moment or on average over a certain period of time), expressed on a 10-point scale or as a percentage of coverage. The modern 10-point scale of cloudiness was adopted at the first Marine International Meteorological Conference (Brussels, city).
When observing on meteorological stations the total number of clouds and the number of low-level clouds are determined; these numbers are recorded in the weather diaries through a fractional line, for example 10/4 .
IN aviation meteorology an 8-oct 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 aviation 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), while the gradations of quantity are used:
- FEW - minor (scattered) - 1-2 octants (1-3 points);
- SCT - scattered (separate) - 3-4 octants (4-5 points);
- BKN - significant (broken) - 5-7 oktants (6-9 points);
- OVC - solid - 8 octants (10 points);
- SKC - clear - 0 points (0 octants);
- NSC - no significant clouds (any amount of clouds with a base height of 1500 m and above, in the absence of cumulonimbus and powerful cumulus clouds);
- CLR - no clouds below 3000 m (abbreviation used in reports generated by automatic weather stations).
cloud shapes
The observed forms of clouds are indicated (in Latin designations) in accordance with the international classification of clouds.
Cloud base height (CLB)
The VNGO of the lower tier is determined in meters. At a number of weather stations (especially aviation ones), this parameter is measured by an instrument (error 10-15%), at the rest - visually, approximately (in this case, the error can reach 50-100%; visual VNGO is the most unreliably determined weather element). Cloudiness can be divided into 3 tiers (lower, middle and upper) depending on the VNGO. The lower tier includes (up to about a height of 2 km): stratus (precipitation may fall in the form of drizzle), stratocumulus (abundant precipitation), stratocumulus (in aviation meteorology, stratified and ruptured rain are also noted) clouds. Middle layer (approximately from 2 km to 4-6 km): altostratus and altocumulus. Upper layer: cirrus, cirrocumulus, cirrostratus clouds.
Cloud top height
It can be determined from the data of aircraft and radar sounding of the atmosphere. It is usually not measured at weather stations, but in aviation weather forecasts for routes and areas of flight, the expected (predicted) height of the top of the clouds is indicated.
see also
Sources
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An excerpt characterizing Cloudiness
Finally, the headman Dron entered the room and, bowing low to the princess, stopped at the lintel.Princess Mary walked across the room and stopped in front of him.
“Dronushka,” said Princess Mary, seeing in him an undoubted friend, that very 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 was dangerous from the enemy. My dear, I can’t do anything, I don’t understand anything, there’s no one with me. I certainly want to go at night or tomorrow early in the morning. Drone was silent. He glanced frowningly at Princess Marya.
“There are no horses,” he said, “I also told Yakov Alpatych.
- Why not? - said the princess.
“All from God’s punishment,” said Dron. - What horses were dismantled under the troops, and which died, now what a year. Not to feed the horses, but not to die of hunger ourselves! And so they sit for three days without eating. There is nothing, ruined completely.
Princess Mary listened attentively to what he was saying to her.
Are the men ruined? Do they have any bread? she asked.
“They die of starvation,” said Dron, “let alone carts…
“But why didn’t you say, Dronushka?” Can't help? I will do everything I can ... - It was strange for Princess Mary 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 was master's bread and that it was given to peasants. She knew, too, that neither her brother nor her father would have denied the need to peasants; she was only afraid to make a mistake somehow in her words about this distribution of bread to the peasants, which she wanted to dispose of. She was glad that she had 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 masterful in Bogucharov.
“We have the master’s bread, bro?” she asked.
“The Lord’s bread is whole,” Dron said proudly, “our prince did not order to sell it.
“Give him to the peasants, give him everything they need: I give you permission in the name of your brother,” said Princess Mary.
Drone did not answer and took a deep breath.
- You give them this bread, if it will be enough for them. Distribute everything. I command you in the name of a brother, and tell them: whatever is ours, so is theirs. We will spare nothing for them. So you say.
Drone gazed at the princess intently while she spoke.
“Fire me, mother, for God’s sake, send me the keys to accept,” he said. - He served twenty-three years, did not do anything bad; quit, for God's sake.
Princess Mary did not understand what he wanted from her and why he asked to be fired. She answered him that she never doubted his devotion and that she was ready to do everything for him and for the peasants.
An hour later, Dunyasha came to the princess with the news that Dron had come and all the peasants, on the orders of the princess, had gathered at the barn, wanting to talk with the mistress.
“Yes, I never called them,” said Princess Marya, “I only told Dronushka to distribute bread to them.
- Only for God's sake, Princess Mother, order them to drive away and do not go to them. It’s all a deception,” Dunyasha said, “but Yakov Alpatych will come, and we’ll go ... and you don’t mind ...
At some height above earth's surface and consist of water droplets or ice crystals, or both. The whole variety of clouds can be reduced to several types. The currently generally accepted international classification of clouds is based on two features: the appearance and the height of their lower boundary.
By appearance clouds are divided into three classes: separate, unrelated cloud masses, layers with an inhomogeneous surface, and layers in the form of a homogeneous veil. All these forms can occur at different heights, differing in the density and size of external elements (lambs, swellings, ridges, ripples, etc.)
According to the height of the lower base above the earth's surface, clouds are divided into 4 tiers: upper (Ci Cc Cs - height more than 6 km), middle (Ac As - height from 2 to 6 km), lower (Sc St Ns - height less than 2 km), vertical development (Cu Cb - can belong to different tiers, and in the most powerful cumulonimbus clouds (Cb) the base is located on the lower tier, and the top can reach the upper one).
Cloud cover largely determines the amount of incoming to the Earth's surface solar radiation and is a source of precipitation, thus influencing the formation of weather and climate.
The amount of clouds in Russia is distributed rather unevenly. The most cloudy are areas subject to active cyclonic activity, characterized by developed advection of wet. These include the northwest of the European part of Russia, the coast of Kamchatka, Sakhalin, the Kuril and. The average annual amount of total cloudiness in these areas is 7 points. Substantial part Eastern Siberia characterized by a lower average annual amount of clouds - from 5 to 6 points. This relatively cloudy region of the Asian part of Russia is within the scope of the Asian.
Distribution of the average annual amount of lower cloudiness in in general terms follows the distribution of total cloudiness. The largest amount of low level clouds also occurs in the northwest of the European part of Russia. Here they are predominant (only 1-2 points less than the amount of total cloudiness). The minimum number of clouds of the lower tier is noted, especially in (no more than 2 points), which is typical of the continental climate of these areas.
The annual course of the amount of both total and lower cloudiness in the European part of Russia is characterized by minimum values in summer and maximum values in late autumn and winter, when the influence is especially pronounced. A directly opposite annual course of the amount of total and lower cloudiness is observed on Far East, And . Here the largest number clouds falls in July, when the summer monsoon bringing from the ocean a large number of water vapor. The cloudiness minimum is observed in January during the period of the greatest development of the winter monsoon, with which dry cooled continental air from the mainland enters these areas.
The daily course of the total number of clouds throughout Russia is characterized by the following features:
1) its amplitude in most of the territory does not exceed 1-2 points (with the exception of the central regions of the European part of Russia, where it increases to 3 points);
2) the number of clouds during the day is greater than at night, while in January the maximum falls on the morning hours; in the central months of spring and autumn, the diurnal variation is smoothed out, and the maximum can shift by different hours of the day; in April, the diurnal variation is closer to the summer type, and in October, to the winter type;
3) the daily course of the lower cloudiness practically repeats the daily course of the general cloudiness.
The distribution of clouds by form is characterized by relative constancy in time and space. Almost over the entire territory of Russia, among the clouds of the upper tier, Ci of the middle tier - Ac of the lower tier - Sc and Ns prevail
IN annual course V summer period there is a predominance of cumulus (Cu) and stratocumulus (Sc), while the frequency of stratus (St) and nimbostratus (Ns), which are frontal, is low, since conditions for active cyclonic activity are relatively rare in summer. The winter, spring and autumn periods in most of Russia are characterized by an increase in the frequency of altostratus (As), altocumulus (Ac) and stratocumulus (Sc) clouds, while in the European part of Russia there is a slight increase in the frequency of stratus and stratocumulus -cumulus clouds (St).
