What causes the wind? Cognitive experimentation lesson “Why does the wind blow?” (senior group)

“Wind, wind! You are powerful...” - every fifth grader knows this by heart. What is your power, where does it come from, how are you born, wind-breeze-wind? Time, as elusive as you, flies and changes century after century, and people still ask the same question: “What is the wind, where does it come from?” Others answer them something, each in their own way. “The wind is born from the trees,” someone says, “the trees sway and move the air.” This version is very cute, but who rocks the trees? “Like who?” answers the hero of the story, “God!”

If this is idle curiosity, it was voiced and forgotten. The wind is blowing outside - that means it’s the way it should be. But what determines your strength and why are you sometimes light and playful, sometimes angry and cruel? This is already a serious question; it is not for nothing that the best scientific minds are constantly studying what wind is and what factors its intensity and direction depend on. Thanks to their discoveries, a person today can predict in which direction and with what force you will blow. But you don’t let yourself be fooled: isn’t the effect of surprise your favorite game?

Sometimes it seems that there are no secrets here. After all, what is wind? In short - the movement of the atmosphere. That is, the flow of air molecules with And what moves these molecules is a topic for a more detailed explanation. In places where warm air accumulates, the atmospheric pressure is low. Air heated by the sun rises to the upper layers of the atmosphere and cools there, then, according to the principle of circulation, it falls down, carrying with it an area of ​​​​high pressure. These temperature changes create atmospheric movement called wind. The greater the differences, the stronger the wind.

Why is it always windy in the mountains and on the coasts? Because in places of contrast atmospheric pressure The circulation of warm and cold air flows occurs continuously, only its intensity changes. This is especially noticeable on the seashore, where you, the wind, frolic day and night. This is because the sun heats the land faster, while the water column warms up slowly. The warm wind rises above the ground in streams, giving way to a cold air flow from the water. And the wind starts to blow. This is what the wind from the sea is, which blows constantly. Although no, at night the reverse movement begins: the earth cools down faster, but the sea still retains heat, and now the wind changes direction - from the shore to the sea.

You are having fun, wind, because our knowledge is too narrow. There are other hypotheses about what wind is. There is a so-called one that also characterizes the movement of air currents during the rotation of the Earth. According to the French scientist Gaspard-Gustav Coriolis, our planet rotates at a higher speed than its atmospheric layer and is deflected, creating currents. And there are also eternal ones, or prevailing winds, blowing along the equator and from the Earth's poles.

They say that a person knows three percent of existence. Does he know? What do you think, wind-breeze-wind? Or we don’t need to know anything, it’s better to stick to simple knowledge: wind happens because the trees sway, and God shakes them...

It's something mysterious. We never see it, but we always feel it. So why does the wind blow? Find out in the article!

Wind is the movement of air masses. Even though we can't see air, we know it's made up of molecules various types gases, mainly nitrogen and oxygen. Wind is a phenomenon in which many molecules move in the same direction.

Where does it come from? Wind is caused by pressure differences in the Earth's atmosphere: air from an area of ​​high pressure will move towards an area of ​​low pressure. Strong winds occur when air moves between areas with huge differences in pressure levels. Actually, this fact largely explains why the wind blows from the sea to the land.

Wind formation

Wind is the movement of air near the Earth's surface. It can be a gentle breeze or a strong storm. The strongest winds occur during events called tornadoes, cyclones and hurricanes. It is caused by changes in air, land and water temperatures. When air moves parallel to a warm surface, it heats up and rises—this leaves room for cooler masses to move in. The air “flowing” into these empty spaces is the wind. It is named by the direction it comes from, not the direction it blows.

Breezes: coastal and sea

Coastal and sea breezes are wind and weather phenomena characteristic of coastal areas. A shore breeze is a breeze that blows from land to a body of water. A sea breeze is a wind that blows from water to land. Why does the wind blow from the sea and vice versa? Coastal and sea breezes arise due to a significant difference in temperature between land and water surfaces. They can extend to depths of up to 160 km or appear as local phenomena that quickly weaken within the first few kilometers along the coastline.

From a scientific point of view...

Land and sea breeze patterns can greatly influence fog distribution and cause pollution to accumulate or disperse across inland areas. Current research into the principles of land and sea breeze circulation also includes efforts to model wind patterns as they affect energy needs (such as heating and cooling requirements) in affected areas. Wind also has an impact on weather-dependent operations (eg aircraft).

Since water has a much higher heat capacity than sand or other materials in the earth's crust, given a certain amount of solar irradiation (insolation), its temperature will rise more slowly than on land. Regardless of the temperature scale, during the daytime the temperature of land can fluctuate by tens of degrees, while that of water varies by less than half a degree. Conversely, high heat capacity prevents rapid changes in liquid temperature at night, and thus, while land temperatures can drop by tens of degrees, water temperatures remain relatively stable. In addition, the lower heat capacity of crustal materials often allows them to cool faster than the sea.

Physics of sea and land

So why is there strong wind blowing? The air above the respective surfaces of land and water is heated or cooled depending on the conductivity of these surfaces. During the day, higher ground temperatures result in warmer and therefore less dense and lighter air masses over the coast compared to those adjacent to the water surface. As warm air rises (the phenomenon of convection), cooler air moves towards the voids. This is why the wind blows from the sea, and during the day there is usually a cool sea breeze flowing from the ocean to the shore.

Depending on the temperature difference and the amount of air lifted, the sea breeze can gust at speeds ranging from 17 to 25 km per hour. The greater the temperature difference between land and sea, the stronger the land wind and sea breeze.

Why does the wind blow from the sea

After sunset, the air mass over coastal land quickly loses heat, while over water it usually does not differ much from its daytime temperature. When the air mass over the land becomes cooler than the air mass over the water, the land wind begins to blow from the land to the sea.

The excitation of warm, moist air from the ocean often results in over coastline daytime clouds. In addition, the movement of air masses and sea breezes are often used by tourists for hang gliding. Although land and sea breezes predominate on sea ​​coast, they are also often recorded near large bodies of water. Coastal and sea breezes lead to increased humidity levels, precipitation and moderate temperatures in coastal areas.

Explanation for children: why the wind blows

Sea breezes are most common on hot summer days due to the unequal heating rates of land and water. During the day, the land surface warms faster than the sea surface. Therefore, part of the atmosphere above the land is warmer than above the ocean.

Now remember that warm air is lighter than colder air. As a result, he rises. This process causes cooler air over the ocean to take up space at the earth's surface to replace the rising warm mass.

However, it is worth knowing that wind is formed not only as a result of differences in temperature. Global atmospheric movements arise as a result of the rotation of the Earth. These winds group the trade winds and monsoons. Trade winds occur near the equator and move either from the north or south towards the equator. In the Earth's mid-latitudes, between 35 and 65 degrees, westerly winds predominate. They blow from west to east, and also towards the poles. Polar winds blow near the north and south poles. They move from the poles to the east or west, respectively.

Our world is full of mysteries and interesting things. Unraveling them is the task of humanity. Even greater discoveries await us, but for now we already know exactly the answer to the question of how and why the wind blows, as well as what factors determine its formation. This makes it possible to predict changes in weather conditions.

General circulation atmosphere- a system of air currents on the globe that promotes the transfer of heat and moisture from one area to another. Air moves from areas of high pressure to areas of low . High and low pressure formed as a result of uneven heating earth's surface. Under the influence of the Earth's rotation, air flows are deflected to the right in the Northern Hemisphere and to the left in the Southern Hemisphere.

IN equatorial in latitudes, due to high temperatures, there is a constantly existing belt low pressure with weak winds. Heated air rises and spreads at altitude to the north and south. At high temperatures and upward movement of air, with high humidity, large clouds form. Falls out here a large number of precipitation.

Approximately between 25 and 30° N. and Yu. w. air descends to the surface of the Earth, where, as a result, belts are formed high pressure. Near the Earth, this air is directed towards the equator (where there is low pressure), deviating to the right in the Northern Hemisphere and to the left in the Southern Hemisphere. This is how they are formed trade winds. In the central part of the high pressure belts there is a calm zone: the winds are weak. Thanks to downward air currents, the air dries out and warms up. The hot and dry regions of the Earth are located in these belts.

IN moderate latitudes with centers around 60° N. and Yu. w. pressure low. The air rises and then rushes to the polar regions. In temperate latitudes, westerly air transport predominates (the deflecting force of the Earth's rotation acts).

Polar latitudes are characterized by low air temperatures and high pressure. Air coming from temperate latitudes descends to the Earth and is again directed to temperate latitudes with northeastern (in the Northern Hemisphere) and southeastern (in the Southern Hemisphere) winds. There is little precipitation.

Winds

Wind- horizontal movement of air relative to the earth's surface. It arises as a result of uneven distribution of atmospheric pressure and its movement is directed from areas with higher pressure to areas where the pressure is lower. The reason for the occurrence of wind is the difference in pressure between territories, and the reason for the difference is heterogeneity in heating. The direction of the wind is determined by the part of the horizon from which it blows (the north wind blows from north to south). The direction of the winds is affected by the deflecting force of the Earth's rotation.

The winds vary origin, character, meaning . The general circulation of winds, caused by the difference in atmospheric pressure, includes: monsoons, zonal transports, cyclones, anticyclones. Local atmospheric circulation is expressed in breezes.

Types of winds.

TO local winds include breezes, mountain-valley, fen, bora, sirocco, samum, etc. IN equatorial belt Low pressure prevails, in the subtropical - high pressure, so the winds blow towards the equator. Under the influence of the Coriolis force, they deviate in the northern hemisphere to the right and have a northeastern direction, in the southern hemisphere - to the left and become southeastern.

Föhn- warm, dry and gusty wind from the mountains. It blows when there is lower pressure on one side of the ridge than on the other. Bora- a strong, cold, gusty wind, formed when cold air passes over low ridges to the warm sea.

Trade winds– constant winds in the tropical regions of the Northern and Southern Hemispheres, blowing from high pressure belts (25-35° N and S) to the equator (to the belt low blood pressure). Under the influence of the Earth's rotation around its axis, the trade winds deviate from their original direction. In the Northern Hemisphere they blow from northeast to southwest, in the Southern Hemisphere they blow from southeast to northwest. Trade winds are characterized by great stability of direction and speed.

In temperate latitudes of both hemispheres, westerly transports dominate ( westerly winds). Temperate westerlies are the predominant winds blowing in temperate zone approximately between 35 and 65 degrees north and south latitude. These winds blow predominantly from west to east, more precisely from the southwest in the Northern Hemisphere and from the northwest in the Southern Hemisphere.

During the day, the land heats up faster than the sea, and the air above it is warmer than above the water. An area of ​​low pressure forms above the land, and high pressure above the water, and the wind blows from the sea to the land. This afternoon breeze. At night, the land cools faster than the sea, over which an area of ​​low pressure forms, and the wind blows in reverse side - night breeze.

The formation mechanism is similar monsoon- seasonal winds that change their direction twice a year: in summer they blow on land, in winter - on the sea. In winter, the air over land is colder, over the ocean it is warmer. Consequently, the pressure is higher over the continent, lower over the ocean. Therefore, in winter, air moves from the mainland (an area of ​​higher pressure) to the ocean (over which the pressure is lower). In the warm season, it’s the other way around: the monsoons blow from the ocean to the mainland. Therefore, in monsoon areas, precipitation usually occurs in summer. Due to the rotation of the Earth around its axis, the monsoons deviate to the right in the Northern Hemisphere, and to the left in the Southern Hemisphere from their original direction.

Special wind systems.

As a result of the uneven heating of the earth's surface and the deflecting force of the earth's rotation, huge (up to several thousand kilometers in diameter) atmospheric vortices are formed: cyclones and anticyclones. Cyclone - atmospheric vortex With low blood pressure in the center. Anticyclone- atmospheric vortex with high blood pressure in the center.

Cyclone – an ascending vortex in the atmosphere with a closed region of low pressure, in which winds blow from the periphery to the center (counterclockwise in the Northern Hemisphere, clockwise in the Southern Hemisphere). The average speed of a cyclone is 35-50 km/h, and sometimes up to 100 km/h. In a cyclone, air rises, which affects the weather. With the emergence of a cyclone, the weather changes quite dramatically: winds become stronger, water vapor quickly condenses, generating heavy cloudiness, and precipitation falls.

Anticyclone - a downward atmospheric vortex with a closed area of ​​​​high pressure, in which winds blow from the center to the periphery (in the Northern Hemisphere - clockwise, in the Southern - counterclockwise). The speed of anticyclones is 30-40 km/h, but they can linger in one place for a long time, especially on continents. In an anticyclone, the air sinks down, becoming drier as it warms up, since the vapors contained in it move away from saturation. This, as a rule, excludes the formation of clouds in the central part of the anticyclone. Therefore, during an anticyclone the weather is clear, sunny, without precipitation. In winter it is frosty, in summer it is hot.

Wind speed scale (Beaufort scale)

Points Beaufort	Wind speed, m/s	Characteristic wind	Apparent wind action
0	0-0,2	Calm	The smoke rises vertically, the leaves on the trees are motionless
1	0,3-1,5	Quiet wind	Light air movement, smoke deviates slightly
2	1,6-3,3	Light breeze	You can feel the movement of air on your face, the leaves rustle
3	3,4-5,4	Light wind	Leaves and thin branches on the trees sway
4	5,5-7,9	Moderate wind	Tree tops bend, small branches move, dust rises
5	8-10,7	Fresh breeze	Branches and thin tree trunks sway
6	10,8-13,8	Strong wind	Thick branches sway, telephone wires hum
7	13,9-17,1	strong wind	Tree trunks sway, large branches bend, it becomes difficult to walk against the wind
8	17,2-20,7	Very strong wind	Large trees sway, small branches break, it is very difficult to walk
9	20,8-24,4	Storm	Minor damage to buildings, thick tree branches breaking
10	24,5-28,4	Heavy storm	Trees break or are uprooted, major damage to buildings
11	28,5-32,6	Fierce Storm	Great destruction
12	32,7-36,9	Hurricane	Devastating destruction

Lesson summary " Wind. Wind systems". Next topic:

Irina Tulenkova
Cognitive experimentation lesson “Why does the wind blow?” ( senior group)

Municipal state preschool educational institution

Kindergarten "Fairy tale".

Cognitive experimentation.

Subject: « Why does the wind blow?»

Tulenkova Irina Yurievna

Educator II

qualifying

MKDOU d/s "Fairy tale"

Tyumen region,

Kondinsky district,

With. Leushi, st.

Volgogradskaya. 56,

tel. (34677) 37-134

With. Leushi 2011

Target: Introduce children with the cause of wind - the movement of air masses.

Tasks:

1. Clarify children’s ideas about properties air: hot rises up - light; the cold one goes down - it is heavy.

2. Strengthen children's knowledge about air.

3. Develop skills in conducting experiments.

4. Improve breathing technique skills.

5. Instill in children the initial elements of environmental culture.

6. Introduce children with such a natural phenomenon as wind, its role in the life of nature and man.

7. Foster a culture of communication, intensify speech activity. Methodological techniques We: Experiments conducted by the teacher together with the children; artistic word (riddles, poems about the wind); breathing exercises; physical training; a game; surprise moment; result; analysis.

Educator: Guys, let's close our eyes and listen, what do you hear? Children: (children's answers).

And I hear the rustling of leaves and imagine how in our the breeze flies through the group, fresh, light. Do you hear?

Or maybe you and I will turn into trees and imagine that breeze sways our branches.

Fizminutka: « The wind blows in our faces» .

Educator: Guys, while we were listening breeze, he visited us group and brought us a balloon. Let's see what it says there. (The teacher reads the note attached to the ball). There is a riddle here, pay attention to it listen:

We need him to breathe, to inflate the balloon. He is next to us every hour, but he is invisible to us.

What is this? (air)

That's right, it's air. And today we will talk about air, we will conduct experiments like real scientists. And for this we have an air transformation laboratory.

(we go into the laboratory)

Educator: Guys, who saw the air? Maybe he doesn’t exist at all? (children's answers) Let's check this with you now.

with BAGS Teacher: What do we have in our bags?

Children: Air.

Educator: What is he like? Do we see him? Why don't we see him?? Why they call him invisible?

Children: The air is transparent, which means everything can be seen through it.

Educator: Guys, look what I have?

Children: Cup.

Educator: What is it made of?

Children: From glass.

Educator: So the glass is glass. Look through it, you see

anything.

Children: Yes!

Educator: So what glass?

Children: Transparent.

Educator: Do you think this glass is empty? Is there anything in it?

(children's answers)

Educator: We'll check now.

WITH GLASS

Educator: There are bowls of water and glasses on the table. You need to turn the glass upside down and slowly release it into the bowl. You need to hold the glass very level. What happened? Does water get into the glass? Why not. (children's answers) Educator: We learned that there is air in the glass and releases water into it. Now let's tilt the glass a little, what appears in the water?

Children: (bubbles)

Educator: That's right, air comes out of the glass, and water takes its place. How else can you see the air?

(children's answers)

Educator: Let's take a straw, put it in the water and blow. What comes out of the water with bubbles?

Children: Air.

Educator: Right. You and I exhaled air, because all people breathe air. When we simply inhale and exhale air, do we see it? Children: No!

Educator: (takes a napkin). Can you see it with a napkin?

Children: Yes!

Educator: And you can also see how we breathe in winter - what comes out of our mouths? Children: Steam.

Educator: Let us show you how our noses breathe.

Breathing exercises:

1. "Breath" Breathe through one nostril and peace will come to you.

I. p. - standing, the torso is straightened, but not tense; close the right nostril with the index finger of the right hand, take a long, long breath with the left nostril, as soon as the inhalation is completed, take a long breath through the nose (4 times,

The same exercise with the left nostril.

2. "Breath". Quiet. We will breathe quietly, we will hear our hearts.

I. p. - o. With. - inhale slowly through the nose, hold your breath for 4 seconds, exhale smoothly through the mouth (2 times).

3. "Air balloons". Now let’s check whether there is a lot of air in our chest. Let's blow up the balloons (children inflate balloons and hold them). Now let's let go a little, how do you feel?

Children: Wind.

Educator: That's right, that's wind. Guys, do you know what it is? wind?

(children's answers)

Educator: Wind- this is the movement of air, it is around us, we do not see it, but it is necessary for all living beings. The wind has power. He can move ships, inflate sails, rotate mills, bend trees. Is it possible the wind can harm a person?

(children's answers)

Educator: Right, the wind varies: a hurricane, tornado, dry wind can harm people, but a light one is calm breeze, brings coolness. yj Over the seas the wind is rushing,

Sails fly like birds.

And salty, like a whim. It is called - (breeze).

The wind is strong and mighty,

He gathered clouds over the house,

The rain beats like a drum

Conductor -

(Hurricane).

If the wind blows hotly,

He's called -

(dry wind)

It drives away sand and dust

Feather grass bends to the ground in the steppe.

This wind, everyone needs to know

It's called - (tornado) He captured everyone in a whirlwind, Spun from all sides.

Ellie in a fairy tale he rushed off

And suddenly he fell silent.

Educator: Do you want to become the wind for a few minutes?

WITH BOARDS.

Educator: Our bowls turn into the sea. And you will be the winds. Let's blow on the water. What happens?

Children: Waves.

Educator: The stronger The wind's blowing, the bigger the waves (but in everything you need to know when to stop). Now let go of the sailing ships, if you blow on it, what will happen?

Children: The ship is sailing.

Educator: Likewise, large sailing ships move thanks to the wind. What happens to the boat if there is no wind? And if the wind is very strong?

Children: Starts wind and the ship may be wrecked.

Educator: Now let’s take a fan and wave it over the water. Why did the waves appear?? The fan moves and pushes the air. The air also begins to move. Means wind- this is air movement. Why does air move? Let's do another experiment.

WITH A CANDLE.

Educator: Let's clamp the candle and place it on a stand on the table. Let's place it in a lamp glass, under which we put some blocks. Hold your hand over the lamp glass. How does this make you feel?

Children: Air is coming out of the lamp glass.

Educator: Now let’s hold a piece of paper cut into thin strips under the lamp glass. What will happen?

Children: The stripes are deviated upward.

Educator: This means that the air is heated and the heated air rises. Guys, what do you think, if we open the door slightly, will it fly towards us? breeze?

(children's answers)

Educator: Let's check.

WITH A CANDLE.

Educator: We bring a lit candle to the slightly open door. If you hold a candle over the top edge of the door, the flame of the candle will deviate towards the street.

If the candle is placed on the floor, the flame will deviate to the side groups. This means that warm air is light, it flows out of our groups on the street, and its place is taken by a cold one.

So it is on the street. Our Earth is heating unevenly. Where it heats up more, streams of warm air are formed, which rush upward, and in their place streams of cold air rush. That's how it works wind. Or maybe it will happen that all the air in the yard will heat up and fly away, and we will have nothing to breathe?

(children's answers)

Leading: That’s right, this won’t happen, if the sun is warming us, then at the same time there is cold weather somewhere. And the air there is colder, which means it’s heavier. Therefore, cold air rushes to where it is warmer, and warm air has already made room by rising upward. So it turns out wind

(show diagram.)

It's clear now who's pushing wind who makes the air fly from place to place? Didn't you guess? Then I’ll give you a hint - it’s the sun. It doesn't warm the earth (evenly) the same, always somewhere colder. And if there were the same temperature on Earth, then there would be no breeze. The clouds would stop. If there was no rain, there would be a drought. Smoke from cars and factories would hang over the cities. So bad weather isn't that bad. After all, at this time, the sun is shining happily for other children far from us.

Educator: How can we determine if on the street wind?

Children: By trees, using a ribbon, a weather vane on a house, a turntable. Educator: Well done guys, we learned a lot of interesting things, let's remember what we have today met?

Which experience did you like best?

What can you praise yourself for?

Educator: To consolidate our knowledge, I give you a pinwheel and, going out into the street, you and I will determine whether there is the wind outside and how it blows.

The relationship between man and the wind has always been extremely closely related to each other. It is from this natural phenomenon that prehistoric times(as, indeed, now) a person’s life often directly depended. With its help, humanity was able to develop crafts and make their lives much easier, which can be observed even in such a banal example as a windmill. It is not surprising that for as long as humanity has existed, so many people have asked and are still asking themselves and each other the question, why does the wind blow?

This riddle still remains extremely difficult to understand not only for a child, but also for an adult. Scientists who study inanimate nature still argue about why the wind blows, where the wind blows from, and where the wind blows.

Scientific and technical encyclopedic Dictionary defines wind as a flow of air masses (a mixture of gases, particles of which fly freely in space), which quickly moves parallel to the surface of the Earth. Another interpretation of the wind says that the wind is a natural phenomenon, causing air masses to move due to certain changes that occur in the environment.

Wind arises due to uneven distribution of pressure in the atmosphere. As soon as it appears, it immediately begins to move from a high pressure zone to a low pressure zone. To put it more simply, why the wind blows, we can safely say that if it were not for the Sun, the land and the oceans of our planet, then after a fairly short time the air would have the same temperature and humidity everywhere, which is why the wind would not blow I would never.

How do air masses move?

Throughout the day, the surface of our planet heats up unevenly. This applies not only to objects that are located at a distance from each other, but also to those that are located very close. For example, over the same period of time, things of a darker color heat up (absorb heat) much more than light-colored ones. The same can be said when comparing water with land (the latter reflects less sunlight).

In turn, heated objects transfer heat unevenly to the air that surrounds them. For example, since the earth heats up much more than the water, during the day air from the earth rises upward, and colder air from the sea comes in its place. At night, the reverse process occurs - while the earth has cooled, the waters of the sea remain warm. Accordingly, the warm air above the sea goes up, and the air from the land goes in its place.

Warmer air rises where it collides with colder air. This happens because heated air becomes light and rushes upward, while cold air, on the contrary, becomes heavier and rushes down. How big difference have temperatures of cold and warm flow, the stronger the wind usually blew. Thus, not only a light breeze arises, but also small whirlwinds, hurricanes and even tornadoes.

The air itself tends to be the same everywhere. When some heterogeneity forms (in one place it is warmer, in another it is colder, in a third there are more gas particles, in a fourth there are fewer), it moves horizontally, trying to eliminate the “inequality”.

A similar process occurs throughout the territory. globe. The warmest place on our planet is the equator. It is here that the heated warm air constantly goes up, and from there it goes either to the North or South Poles. After this, at certain latitudes it descends again to the ground and begins to move. Where exactly the wind blows depends on the circumstances. Maybe further to the poles, or maybe back to the equator.

Earth Rotation

The flow of air masses is affected by the rotation of our planet. It is because of it that all the winds that blow in the Northern Hemisphere shift to the right, and in the Southern Hemisphere - to the left.

Atmosphere pressure

Our body, without even knowing it, constantly feels air pressure - despite the fact that it seems absolutely weightless to us. According to the latest scientific data, the entire atmosphere of our Earth (in other words, the layer of gases), consisting mainly of nitrogen and oxygen, weighs five quadrillion tons.

Atmospheric pressure is different in different places on Earth. Gas molecules strive to compensate for this, and constantly move at great speed in different directions (these particles, due to the force of gravity of the Earth, are completely attached to it, and cannot fly into space in any way).

This is how it turns out that wind is the movement of a huge number of molecules of atmospheric gases in one direction. Air masses usually flow from an area of ​​high pressure (when the air is cold - an anticyclone) to an area of ​​low pressure (when it is warm - a cyclone), thereby filling the voids of rarefied air.

Wind classification

Strong winds that have an average duration (one minute) are squalls. There are these types of winds:

• Breeze – warm wind near the sea, where you can observe a light wind blowing on the coast. The wind direction changes twice during the day. The daytime (or sea) wind often blew from the sea to the shore, and the nighttime (or coastal) wind - vice versa. The breeze speed is usually from 1 to 5 m/s;
• A storm is an extremely strong wind, the speed of which ranges from 16 to 20 m/s.
• Storm – occurs during a cyclone, speed – from 15 to 32 m/s;
• A hurricane is a very strong storm, which was caused by air masses moving in different directions at enormous speed, the speed of which is from 32 m/s;
• A typhoon is a hurricane of enormous destructive power that blew and blows mainly near the eastern coast of Asia, on Far East, as well as the western Pacific Ocean.

Gusts of wind are short-term (several seconds) and strong (several hours and even months) movements of air masses. For example, for tropical climates the following types of winds are distinguished:

• Monsoons are winds, characteristic mainly of tropical regions, that blow for several months, sometimes changing the direction of the wind. In summer - from the ocean to land, in winter - vice versa. At the same time, the summer monsoons are characterized by high humidity.
• Trade winds - such a wind usually blows and blows in tropical latitudes throughout the whole year, in the Northern Hemisphere - from the northeast direction, in the Southern Hemisphere - from the southeast. They are separated from each other by a windless strip.

Due to the constant change in pressure, the direction of the wind is constantly changing. But in any case, the wind always moves from an area of ​​high pressure to an area of ​​low pressure.

For thousands of years, people have been observing the winds, drawing certain conclusions, putting forward hypotheses, and drawing up graphs in order to make the best use of this in their activities. amazing phenomenon inanimate nature. Thus, the so-called Wind Rose appeared - a drawing, or more precisely, a diagram that depicts exactly how the wind blows in a particular area.

The Wind Rose is made in this way: eight straight lines are drawn from the center at a distance of 45° from each other, on which marks are applied with a length proportional to either the frequency of the winds or their speeds. After this, the ends of the marks are connected and two polygonal figures are obtained - the Wind Recurrence Rose and the Wind Speed ​​Rose.

The wind rose makes it possible to determine the direction, strength, and duration of the prevailing wind, as well as the frequency of air currents. The compass rose is drawn both to determine the average values ​​and to determine the maximum values. You can create a complex drawing on which diagrams will be drawn, consisting of several parameters at once, which will also show where the wind is blowing.

The drawings are extremely necessary for a person– during construction, to solve various economic problems (for example, recently, thanks to the wind, it has become possible to obtain electricity), etc. After all, the wind may well be both a friend and an enemy - if you do not pay attention to it and do not take into account its influence on environment, he is quite capable of causing irreparable damage by destroying a man-made creation. Although the wind is a phenomenon uncontrollable by man, since it has blown and will blow wherever it wants, but now humanity can predict its approximate direction and strength, which can save many lives.