Municipal budgetary educational institution
"Secondary school No. 9" EMR Saratov region
Research
on the topic "Fog"

Completed by Zhupikov Vladislav
student of 2nd grade "B" MBOU "Secondary School No. 9"
Curator Ivashchenko E.R.
Research work on the topic "Fog"
I like to read books very much. And my favorite fairy tale is Sergei Kozlov’s “Hedgehog in the Fog.” A poor hedgehog got lost in the fog. Is it really possible to get lost and lose your way in the fog?
In the lesson about the surrounding world, we studied the topic: “Phenomena of Nature” and the teacher told us about fog.
And after some time, Novosti reported that due to fog in some cities of our country, flights were delayed and accidents occurred.

Therefore, I decided to figure out what fog is, where it came from, whether it is possible to reproduce fog at home, how this natural phenomenon was reflected in literature and art and music.
Purpose of the study: To study the causes of fog. Objectives: 1. Find out how fog is formed. 2. Find out what types of fog exist. 3. Find out, study and identify safety measures when driving in fog. 4. Consider a natural phenomenon from the point of view of literature, art and music. 5. Try to reproduce the fog at home. 6. Draw conclusions about the research done.
How I did the research
Worked with reference literature;
Turned to online resources;
Conducted experiments on creating fog at home.
What is fog?
Fog is an atmospheric phenomenon, an accumulation of water in the air when tiny particles of water and ice crystals form at temperatures below −15. (from Wikipedia)
Fog1. Opaque air saturated with water vapor or ice crystals. 2. A veil of dust (or smoke, steam, soot), making the air opaque3. About the state of ambiguity, confusion of thoughts and ideas. (Figurative meaning) (Ozhegov’s Explanatory Dictionary)

Fog is a natural phenomenon when a high content of water vapor is formed in the atmosphere. It mainly occurs from the contact of cold and warm air. Fogs occur at any time of the year, but most often they occur in late summer or autumn, when the air cools faster than the ground cools. As a result, cool air falls to the ground or water, which still retains heat, condensation occurs, and many water droplets hang in the air. It looks like a huge cloud is hanging right above the ground or a body of water. In the place where the fog formed, the air humidity is 100%.

Types of fogsThere are different fogs (natural and artificial)
Haze is the weakest type of fog.
Ground fog is fog that spreads over the ground or body of water in a thin layer. This fog does not have much effect on visibility.
Translucent fog. Through such fog the sun and clouds are visible.
Complete fog, when a whitish cloud envelops the earth, through which it is impossible to see literally anything at arm's length. With such fog, traffic becomes impossible.
Smog is an artificial fog consisting of dust, smoke, exhaust gases, chemicals, and other combustion products. Smog is one of the most important problems of modern cities, as it causes irreparable harm to human health and pollutes the environment.

Safety measures when driving in fog.
According to world statistics, of all accidents that occurred in fog, about 77% were collisions with a car moving in front. It turned out that the majority of drivers conscientiously tried to maintain a safe distance between cars, not realizing that to the human eye all objects in the fog appear approximately twice as distant as they actually are. During such weather conditions, drivers should reduce their speed, turn on the sidelights or fog lights and try to avoid overtaking, and most importantly, increase the intervals. However, many drivers and pedestrians do not perceive fog as a danger. Therefore, when driving in fog, all road users need to be extremely careful on the road and strictly follow the Traffic Rules.
Study of how fog is formed (practical work)
I will need:
1.Empty decanter with a narrow neck
2.Hot water
3.A few drops of alcohol
4.Ice cubes
5.Pipette
To make the mist, I first filled the carafe a third full with hot water.
I dropped a few drops of alcohol into the decanter using a pipette.
He took an ice cube and held it over the neck of the decanter. A fog formed in the decanter.
Poetic image of fog in the works of great poets
"The fog has whitened
Birches
And whitened the daisies... (G. Novitskaya)
“The light of day has gone out,
The evening fog fell on the blue sea...” (A.S. Pushkin)
“The fields are compressed, the groves are bare,
There is fog and dampness from the water...
Spicy wind. The dawns are going out.
Fog is creeping across the grass...” (S. Yesenin)
“The forest is in your pocket,
Fields - in pocket
Hid it
Grandfather Fog.
Hid it
Haystacks and haystacks,
And lawns
And meadows..."
(A. Ekimtsev)
“A gray old fog was walking,
He hid the river in his pocket!
Hid the garden
garden fence
and a large herd of cows,
Even the Pacific Ocean
put it in my pocket!...”
(Ivan Demyanov)
The image of fog in musical works
Vladimir Markin - Lilac fog
Fog, fog (film "Chronicle of a Dive Bomber")
Sofia Rotaru – Fog
Dobrynin Vyacheslav -Blue fog
The image of fog in the works of artists
Morning fog.
Artist Kurgina Marina Yurievna

Fog.
Artist Ksenia Chernomor

Conclusions about the work done
Fog is a cloud that has “descended” to the surface of the earth, that is, tiny droplets of water in the air. These droplets are formed either by the evaporation of bodies of water that are warmer than the air surrounding them. Most often, fogs form in the fall, at night or in the morning, when the surface of reservoirs cools more slowly than the air above it. There are several types of fog. I learned how to create mist at home. When studying a natural phenomenon, I became convinced that fog is a phenomenon that amazes with its diversity and unusualness. Reproductions of paintings, poems by poets and songs allowed me to see the beauty of this natural phenomenon.
This was a real discovery for me!

Description of the presentation by individual slides:

1 slide

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Project “Clouds, fog, dew. Amazing natural phenomena...” Performed by: Mikhail Barbanyaga, Alexandra Kosolapova, Mikhail Naumov. Pupils: 3rd grade Leader: Shulga I.V. primary school teacher Chekhov -2017

2 slide

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Relevance Clouds play a big role in our lives. . Climate change depends on their quantity and quality. Rain, snow - these natural phenomena are closely related to clouds. Purpose of the work: Find out: - what physical processes underlie the formation of clouds and their movement, - why rain falls from clouds in summer and snow in winter. Conduct appropriate experiments to confirm the hypotheses. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

3 slide

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Observe the types of clouds and classify them. Find out why evaporated water rises. Determine under what conditions it rains. Tasks Project Manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

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“You have no taste, no color, no smell, you cannot be described, they enjoy you without knowing what you are! It cannot be said that you are necessary for life! You are life itself!” Antoine de Saint-Exupéry Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

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We often watch the clouds. We observed them at different times of the year and at different times of the day. White swans live in the sky. Swans float smoothly across the sky. White feathers curl slightly. Hello, Swans - clouds Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

6 slide

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Their bizarre shapes help you fantasize. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

7 slide

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Why do clouds form? Why are they always so different? What makes them move across the sky and under what conditions does rain fall? These questions interested us. And to answer them we went to the library. Hypothesis: Clouds and storm clouds are made of water. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

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From a scientific article in the encyclopedia Project leader Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena...” “The cloud consists of very tiny droplets of water and ice crystals. The tiny droplets of water that make up the clouds merge into larger droplets, and the cloud darkens. Gradually the drops become heavier and fall out as rain.”

Slide 9

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Warm air rises. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena…” To test this hypothesis, we conducted the following experiment: We poured water into a fireproof vessel and heated it to a boil. When water is heated to a boil, it turns into steam. It is lighter than air and rushes upward.

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The rising air cools and the steam turns into water droplets. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..." We held a chilled glass and saucer over a vessel with boiling water, soon droplets of water appeared on them, which gradually increased and fell

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Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

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“The water splashed merrily in its native sea element. But one day a crazy idea came into her head to reach the sky itself. She turned to the fire for help. With his scorching flame, he turned the water into tiny droplets of warm steam, which turned out to be much lighter than air. The steam immediately rushed upward, rising into the highest and coldest layers of air. Once at the sky-high heights, the droplets of steam became numb, so that they could not touch their teeth from the cold. To keep warm, they huddled closely together and, becoming slightly heavier than air, immediately fell to the ground in the form of ordinary rain. Sick with vanity, the water ascended to the sky, but was expelled from there. The thirsty earth swallowed up every drop of rain. And the water had to serve its punishment in the soil for a long time before it could return to the sea.” Leonardo da Vinci Project Manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

Slide 13

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Watching the clouds, we thought: Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena...” “Are clouds really as light as we think?”

Slide 14

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Problem question: - Do clouds have mass? Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..."

15 slide

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Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena…” - Clouds have mass. A large cloud can weigh several tons. Tiny droplets of water fall down all the time, but as they fall, they evaporate again. And that's why the clouds never disappear. Inside the clouds, some of the droplets freeze, and powerful air currents push water droplets and ice pieces together. As a result, oppositely charged particles are formed in the cloud. Their accumulation leads to a lightning discharge, forming thunderclouds.

16 slide

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Cirrus clouds Cirrus clouds are upper-tier clouds; they form only at altitudes above 6 kilometers. These are delicate clouds of white color, wavy or thread-like. Cirrus clouds never produce precipitation. But it is precisely these clouds that can tell you that in 12-36 hours the sky above you will be covered with solid clouds, which will bring with them heavy rains. Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena..." Cumulus clouds Cumulus clouds are very familiar to all of us. On clear summer days, these clouds appear in the sky by noon, slowly float somewhere and disappear by evening. These cumulus clouds have another name - fair weather cumulus clouds. Stratus Clouds Stratus clouds are a uniform gray layer of clouds that gives the entire sky the same gloomy, overcast appearance. These clouds may bring rain, but the rain will not be as heavy as the rain brought by nimbostratus clouds.

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Fog Fog is opaque air saturated with water vapor. How are fogs formed? Project manager Shulga I.V. Theme: Clouds, fog, dew. Amazing natural phenomena...” Fog is something like a veil of tiny drops of water, sometimes mixed with smoke and dust. Sometimes the fog is so thick that it is very difficult, even impossible, to see anything, as if the clouds had descended to the ground. Fog forms when air cools and water vapor turns into water droplets. Over the sea, fog occurs when the air is warmer than the water.

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Presentation on the topic: How does fog occur?

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What is fog? Fog is a form of condensation of water vapor in the form of microscopic drops or ice crystals, which, collecting in the ground layer of the atmosphere (sometimes up to several hundred meters), make the air less transparent. The formation of fogs begins with the condensation or sublimation of water vapor on condensation nuclei - liquid or solid particles suspended in the atmosphere. Fogs of water droplets are observed mainly at air temperatures above −20 °C, but can also occur at temperatures below −40 °C. At temperatures below −20 °C, freezing fogs predominate. The highest number of foggy days at sea level - an average of more than 120 per year - is observed on the Canadian island of Newfoundland in the Atlantic Ocean. Fogs occur more often in populated areas than far away from them. This is facilitated by the increased content of hydroscopic condensation nuclei (for example, combustion products) in urban air. Fogs prevent the normal operation of all types of transport, so fog forecasts are of great economic importance. Artificial creation of fogs is used in scientific research, in the chemical industry, heat engineering and other fields.

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What causes fogs? Any fog, as a rule, occurs under the influence of several factors. On this basis, a genetic classification of fogs was built. A decrease in air temperature is one of the main reasons for the condensation of water vapor both near the earth's surface and in the free atmosphere. Due to the decrease in temperature, the most intense fogs are formed. Depending on the type of process leading to cooling, they distinguish: radiation and advection fogs and orographic fogs. Radiation fogs are formed as a result of cooling of the earth's surface and the adjacent layer of air under the influence of radiation and turbulent mixing. It is usually believed that during the formation of radiation fogs, the proportion of water vapor when the air is cooled to the dew point remains almost constant. A decrease in temperature below the dew point is accompanied by condensation of water vapor, which leads to a decrease in the proportion and pressure of water vapor. For fog to form, a certain amount of water vapor must condense. Favorable conditions for the formation of radiation fogs are: the absence of clouds or the presence of clouds only in the upper layer. An increase in the number of clouds and a decrease in their height leads to increased counter-radiation of the atmosphere and a decrease in the effective radiation of the earth's surface, which does not contribute to the cooling of the latter; high relative humidity at the initial moment. The higher the relative humidity, the less cooling required to achieve saturation and fog formation.

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Artificial fog. Artificial creation of fogs is used in scientific research, in the chemical industry, heat engineering and other fields. How does artificial fog help agriculture? The most effective technology for growing plants is the method of green cuttings, which can be used to propagate many plants - roses, chrysanthemums, grapes, many fruit and berry crops, even tomatoes. For the plant to take root, the air humidity must be close to 100%, because... green cuttings with leaves do not have their own root system and can receive moisture, as well as nutrition, only through the leaves. Therefore, seedlings are grown in greenhouses, where water is sprayed from time to time, supplied under pressure of several tens of atmospheres, forming a fog consisting of droplets no larger than 30 microns in size. Fog from larger droplets quickly settles. Fog in a greenhouse not only saturates the air with moisture, but can also lower the temperature in it by several tens of degrees, taking away the heat necessary for evaporation, which makes it possible to use greenhouses in hot climates. When growing outdoors, creating artificial fog during night frosts directs the heat radiated from the Earth to warm the plants. This occurs due to the fact that water vapor intensively absorbs infrared radiation.

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1) Types of fogs. According to the method of occurrence, fogs are divided into two types: Cooling fogs - are formed due to the condensation of water vapor when the air is cooled below the dew point. Evaporation fogs are evaporation from a warmer evaporating surface into cold air over bodies of water and wet land areas. In addition, fogs differ in the synoptic conditions of formation: Intramass fogs - formed in homogeneous air masses. Frontal - formed at the boundaries of atmospheric fronts.

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Finding yourself in the middle of a continuous white cloud, so dense that it is almost impossible to distinguish anything at arm's length, you often ask yourself the question: why such a thick fog formed, why is it white and you begin to think about how long this phenomenon usually lasts, and also why any fog dissipates.

Fogs are formed when drops or ice crystals accumulate in the air in the lower layers of the atmosphere, due to which a cloud-like veil is formed along the earth's surface, limiting visibility so much that space beyond one kilometer is not visible, and in some cases objects become difficult to distinguish even at a distance several meters.

If the ambient temperature exceeds -10°C, the vapor blanket consists only of droplets. If the temperature fluctuates from -10 to -15°C, it is made up of water droplets and ice crystals, and when it is -15°C outside, the fog consists of small ice crystals, shimmering in the light of night lamps.

Why this phenomenon occurs is not difficult to answer: its appearance is due either to the evaporation of water from a warm surface into cold air, or to the cooling of warm air currents saturated with moisture. For example, the appearance of ground clouds can often be observed in the evening or in the morning after the temperature of the soil and vegetation (grass) drops; the lower layers of the atmosphere cool so much that they begin to release excess moisture in the form of water droplets.

Another example, this time in winter, is fog over a river, lake or other body of water, on the ice of which an ice hole has formed: in cold weather there is always a veil over it, spreading over the water surface. This happens because the temperature of the water during frost is warmer than the ice surrounding it and the air in contact with it (because of this, the air above the water is always warmer than the rest and there is almost always fog over the river in the area of ​​the ice hole).

After warm air mixes with cold air currents, it begins to cool, releasing steam and forming a cloud at the very surface of the Earth. Therefore, the fog over the river and other bodies of water is usually stable and long-lasting: cold and warm air currents and currents constantly mix here.

A striking example of this phenomenon is the Canadian island of Newfoundland located in the Atlantic Ocean. Due to the fact that two currents collide with each other here – the warm Gulf Stream and the cold Labrador Stream, local residents are forced to spend about one hundred and twenty foggy days a year among the haze.

Formation of terrestrial clouds

When air saturated with water vapor cools or mixes with colder air currents, droplets begin to be released into the atmosphere. After this, if there are tiny particles of dust above the earth’s surface, they begin to stick to them, layering on top of each other and forming drops of larger sizes (the more dust in the air, the faster a cloud forms, so large cities are almost always shrouded in a weak, almost imperceptible veil) .

In the warm season, the size of such a drop ranges from 5 to 15 microns, during frosts - from 2 to 5 microns, so winter cold fog is not as thick as summer fog. As soon as the drops reach the required volumes, objects turn out to be blurry and difficult to distinguish: the air becomes whitish in heavy fog and bluish in light fog.

The answer to the question of why this phenomenon comes in different colors is simple: smaller droplets scatter short blue rays better, while in dense ground clouds larger droplets and light waves scatter all rays equally, regardless of their length.

The water content of such clouds usually does not exceed 0.5 g/m3, but sometimes dense fog can contain up to 1.5 g/m3 (this water is enough for plants to receive the necessary moisture, this is especially important for vegetation in the arid regions of the planet). How impenetrable the shroud will be depends largely on the humidity of the air, which is usually between 85 and 100% during the occurrence of ground clouds:

• if visibility does not exceed 50 meters, thick fog is observed, and the number of drops is 1200 per cubic centimeter;
• if the space is visible at a distance of 50 to 500 meters - moderate (water drops in this case from 100 to 600);
• if visibility is a kilometer - weak (drops - from 50 to 100).

Fogs are also common during frosts, and the phenomenon can be seen even when the humidity does not exceed fifty percent. They can usually be observed in cities, especially at railway and bus stations, where the haze is formed by steam that appears during the combustion of fuel and is released into the air through chimneys and exhaust pipes.

Kinds

Terrestrial clouds do not always owe their origin only to nature: a large number of fogs occur in cities, and therefore they consist not only of drops and dust, but also smoke, soot, which are emitted by factory or chimneys, or arise after or during fires, when a forest, peat or steppe burns. Based on their origin, meteorologists divide fogs into dry (smoke, soot, etc. are to blame for their formation) and wet (only water and dust are involved), and often the second form flows into the first.

In turn, wet fogs, the formation of which is directly influenced by nature - this is evening, night or morning fog (this period is optimal for the formation of clouds creeping along the ground), meteorologists are also divided into groups:

1. Underground. Evening or morning fog that spreads low over the earth's surface or body of water (for example, fog over a river). The shroud may be continuous, or it may be in separate wisps, and visibility will not exceed a kilometer.
2. Translucent. Despite the fact that visibility along the surface is low and in some cases does not exceed several meters, clouds can be clearly distinguished in the sky. This type includes night, evening, and morning fog.
3. Solid. Visibility of dense fog is very limited and often does not exceed fifty meters. The sky is almost invisible, so it is almost impossible to distinguish clouds. This is mainly evening, night and morning fog, and during cold weather when temperatures rise, cold fog can be seen during the day.

Why do fogs disappear?

The duration of this phenomenon varies and can range from half an hour to several days (especially during cold weather or when warm and cold air and water currents collide, for example, fog over a river). The main reason why any fog dissipates is the air warming up. Since the veil forms near the surface, after the sun's rays warm it up, the air also heats up, as a result of which the droplets evaporate and turn into steam.

The higher above the earth's surface, the weaker the fog dissipates, since in the upper layers of the atmosphere the air temperature begins to drop again, the steam transforms into water droplets and forms clouds.

Fog. Causes
emergence
The work was done by a student of the 2nd
course
Anokhina Yana

Tumaan - atmospheric
phenomenon, accumulation
water in the air when
tiny particles are formed
condensation products
water vapor (at
air temperature
above −10° -
tiny droplets
water, at −10..−15° -
a mixture of water droplets and
ice crystals, with
temperature below −15°
- ice crystals,
sparkling in the sun
rays or in the light of the moon and
lanterns).

General information
Relative humidity
in fogs it is usually close to 100
% (at least exceeds
85-90%). However, in strong
frosts (−30° and below) in
settlements, on
railway stations and
fog may occur at airfields
be observed at any
relative air humidity
(even less than 50%) - due to
water vapor condensation,
formed during combustion
fuel (in engines, stoves, etc.)
etc.) and thrown into
atmosphere through the exhaust
pipes and chimneys.
Continuous duration
fogs usually range from
several hours (and sometimes
half an hour to an hour) to several days,
especially during the cold season
of the year.

Fogs hinder
normal work of all
types of transport
(especially aviation)
so fog forecast
has a large national economic
value.Artificial
creating mists
used for scientific
research, in
chemical
industry,
heating engineering, combating
plant pests and
other areas.

Types of fogs
The following types of fog are noted at weather stations:
Translucent
fog
Complete fog
underground fog

Ground fog
Ground fog - fog, low
creeping over the earth
surface (or body of water)
a continuous thin layer or
in the form of separate shreds, so that in
layer of fog horizontal
visibility is less than 1000
m, and at a level of 2 m - exceeds
1000 m (usually about
in haze, from 1 to 9 km, and sometimes
10 km or more). It is observed how
usually in the evening, night and
morning hours. Separately
ground ice observed
fog - observed at
air temperature below
−10..−15° and consisting of
ice crystals sparkling in
sun rays or moonlight
and lanterns.

Translucent fog
Translucent fog - fog with
horizontal visibility at level
2 m less than 1000 m (usually it
is several hundred meters, and
in some cases it decreases even to
several tens of meters), weak

it is possible to determine the state of the sky
(number and shape of clouds). More often
observed in the evening, at night and in the morning,
but can also be observed during the day,
especially in the cold half of the year when
increasing air temperature.
Separately noted is the translucent
ice fog - observed during
air temperature below −10..−15° and

sparkling in the sun's rays or
the light of the moon and lanterns.

Complete fog
Fog - continuous fog with
horizontal visibility on
2 m level less than 1000 m (usually
it amounts to several hundred
meters, and in some cases
decreases even to several
tens of meters), enough
developed vertically, so
impossible to determine
state of the sky (amount and
cloud shape). More often
observed in the evening, at night and
in the morning, but can also be observed
during the day, especially in the cold
half a year if promoted
air temperature. Separately
there is freezing fog -
observed at temperature
air below −10..−15° and
consisting of ice crystals
sparkling in the sun's rays
or in the light of the moon and lanterns.

Fog classification
By method
occurrence of fogs
are divided into two types:
Cooling fogs -
are formed due to
water condensation
steam during cooling
air below point
dew.dew
Mists of evaporation -
are vapors from
warmer
evaporative
surfaces in cold
air over bodies of water and
wet areas
sushi.

Moreover, the fogs
vary in
synoptic
conditions
education:
Intra-mass -
emerging in
homogeneous
air masses.
Front -
formed on
borders
atmospheric
fronts.

Massive fogs inside
Sea fog
Radiation mists
Advective fogs

Radiation mists
fogs that appear in
as a result of radiation
cooling the earth's surface
and masses of wet ground
air to dew point. Usually
radiation fog occurs
at night in anticyclone conditions
in clear weather and
light breeze. Often
radiation fog occurs
under temperature conditions
inversion preventing
rise of air mass.
After sunrise
Radiation mists are usually
quickly dissipate. However, in
cold season in
stable anticyclones they
can persist during the day, sometimes
many days in a row. IN
industrial areas may
an extreme form occurs
radiation fog - smog.

Advective fogs
formed due to cooling
warm moist air when
moving over colder
surface of land or water. Their
intensity depends on the difference
temperatures between air and
underlying surface and
air moisture content. These
fogs can develop as above
sea ​​and over land and cover
huge spaces, in separate
cases up to hundreds of thousands of km².
Advection fogs are usually
occur in cloudy weather and
most often in warm sectors
cyclones. Advective fogs
more stable than
radiation, and often not
dissipate during the day.

Sea mists
advective fog,
arisen over the sea
during the transfer
cold air on
warm water. This
the fog is
mist of evaporation.
Fogs of this type
frequent, for example, in
Arctic, when the air
falls from the ice
cover on open
sea ​​surface.

Frontal and dry fogs
Frontal fogs
EditFrontal fogs form near
atmospheric fronts and move with them.
Saturation of air with water vapor occurs due to
evaporation of precipitation falling in the front zone. Some
plays a role in increasing fog before fronts
the drop in atmospheric pressure observed here,
which creates a slight adiabatic depression
air temperature.
Dry fogs
EditTo fogs in colloquial speech and in
fiction is sometimes referred to as the so-called
dry fogs (haze, haze) - significant deterioration
visibility due to forest, peat or steppe smoke
fires, either due to loess dust or part of the sand,
lifted and carried by the wind, sometimes for significant
distances, as well as due to industrial emissions
enterprises. The transitional stage between dry and
wet fogs - such fogs consist of water
particles together with sufficiently large masses of dust, smoke and
soot. These are the so-called dirty city fogs,
resulting from the presence of large quantities in the air
cities mass of solid particles emitted during combustion
smoke, and even more so - factory
pipes.

Why does fog appear?
Many people would be interested
find out why it appears
fog and what it is like
is. Fog
usually called
meteorological phenomenon
during which in the air
high
water vapor concentration. IN
warm weather fog
represents
accumulation of small drops
water, and when cold to them
small ones are added
ice crystals that
in sunlight they can
shine.

Mechanism of fog formation
The formation of fog occurs at those moments
when cold air comes into contact with warm air
humidity more than 85%. In populated areas it is
the phenomenon can also occur with relatively
little humidity. This happens in
as a result of condensation of water vapor,
arising during combustion of various types
fuel. It should be noted that the origin
fog is not always natural, it can
be artificial. Similar mists carry
name of radiation. They are formed due to
cooling air under the influence of radiation.
Natural fogs are thicker
consistency than artificial ones, but
they can last from several
hours to several days. In fact, fog can
call a cloud that forms over
surface of the earth or water. Mostly fog
appears in lowlands and over water bodies early
in the morning or at night. Why is this happening?
exactly? This is due to the fact that when it is cold
air comes into contact with warm soil or water,
moisture begins to condense and a lot of
drops of water simply hang in the atmosphere. In
place where fog occurs, relative
Air humidity is approaching 100%.

The structure of fog directly depends on temperature
air. At temperatures above -10 degrees cloud
consists of very small drops of water, from -10 to -15
degrees is a mixture of water and the smallest
ice crystals, if the temperature is below -15
degrees, then the cloud will consist entirely of
ice crystals. As for the populated
points, then the fog there will be denser due to
condensation of steam from exhaust gases. By level
visibility fogs can be divided into several
types: haze, ground, translucent and
solid. A very faint cloud is called a haze.
Ground fog is the one that spreads over
surface of water or land thin continuous
layer and has little effect on visibility. Visibility
with translucent fog it ranges from tens
up to hundreds of meters, but you can see through it
clouds, sky, moon and stars. As for the continuous
fog, then it is a whitish cloud,
through which it is almost impossible to see
even large objects at a distance of tens
meters. Being in it, you feel very noticeably
dampness, and also almost impossible to see
clouds, sky and sun. This phenomenon makes it difficult
movement of many types of transport, especially
airplanes.