The change of seasons on earth is a common occurrence. We are so accustomed to the fact that the seasons successively replace each other that we practically do not notice it. But it is with the onset of each new season that our entire way of life changes.

The time of year determines the choice of clothing and recreational activities. So in the summer we go on vacation and pick mushrooms and berries, in the fall we make beautiful compositions from fallen leaves and gifts of nature, in the winter we build snow forts and play ice hockey, in the spring we admire the flowering of plants and trees and enjoy the onset of warmth.

Why do the seasons change

There are only four seasons. They are also called seasons of the year. Summer differs from winter in the length of the day: summer nights are shorter than winter ones. Spring and autumn are periods when summer gradually turns into winter and vice versa.

If we talk about the central part of Russia, here the seasons of the year have the following characteristics:

• Spring. Nature awakens from a long winter sleep. It's getting warm. Plants begin to actively bloom.

• Summer. At this time there is a maximum increase in air temperature. Plants reproduce and bear fruit.

• Autumn. Gradual decrease in air temperature. Plants slow down their growth, nature is preparing for the onset of winter.

• Winter. Cold, precipitation in the form of snow. Nature plunges into a long winter sleep.

Why do the seasons change? What is the essence of this natural phenomenon? In order to clearly imagine the meaning of what is happening, you need to understand how the globe moves in outer space, then the reason for the change of seasons will become quite obvious.

There are two types of this movement:

• In one day, planet Earth completely rotates around its axis (this is the name of the conventional line passing through the northern and South Pole). That is why there is a change of day and night. People living on continents facing the Sun are awake, while those living on the opposite hemisphere are asleep.

• Over the course of a year, the Earth, moving around the Sun in an orbit resembling an ellipse, makes a full revolution.

There are two points in the Earth's orbit:

• Perihelion. The distance between it and the Sun is 147 million km. Closest to the Sun.

• Aphelion. It is 152 million km away from the Sun, therefore it is the farthest point.

As you can see, there is a difference between these points, which is estimated to be approximately 3%. As a result, the amount of solar energy received at two points is not the same, the difference is about 7%. But if you think that it is warmer at that point of the Earth that is closer to the Sun, you will be mistaken. January, the peak of winter cold, occurs in the Northern Hemisphere when our planet is at perihelion.

It turns out that the position of the Earth relative to the Sun does not affect the change of seasons. A much more important factor is its tilt angle, which is 23.5°. When the Earth makes a yearly revolution around the Sun, both hemispheres turn to face the star in turn. Accordingly, continents directed towards the Sun receive more light, and summer begins there. On the opposite side, receiving three times less heat, winter begins.

You may ask, what would happen if this angle did not exist? In this case, it would be impossible to distinguish the concept of “seasons”. After all, the Earth would rotate vertically, all its points would be at the same distance from the star, and therefore would receive the same amount of heat.

So, the answer to the question of why winter or summer comes is simple. The change of seasons occurs because the Earth rotates around the Sun at a certain angle of inclination.

Why do the seasons change? Encyclopedia for children

Change of seasons in the earth's hemispheres

Now you understand how and why the seasons change on Earth. Let's take a closer look at how they change in the Northern and Southern Hemispheres.

As we approach the Sun, summer begins on the continents of the Northern Hemisphere. The days become long, and in regions that are closer to the pole, it is light even after midnight. Then, moving in orbit, the Earth finds itself on the opposite side from the Sun, and due to the influence of the angle of inclination, the Northern Hemisphere moves away from sunlight and heat, which marks the arrival of winter on its continents.

Please note that people living in countries in the equatorial and tropical zones are not familiar with winter frosts. The fact is that the position of the equator relative to the Sun is practically not affected by the movement of the globe in its orbit. Therefore, the seasons here are not as contrasting as, for example, in Russia, and the transition from one season to another is very smooth.

The astronomical phenomenon of the transition of the Sun from one hemisphere to another is called an equinox.

Dates of the equinoxes:

• Spring. Occurs from March 20 to 21. At this time, the Sun gives more heat to the Northern Hemisphere.

• Autumn. Observed from September 22 to 23. The sun is heading towards the Southern Hemisphere.

If you were wondering why, for example, in South America winter is a hot season, then, having this knowledge, you can easily find the answer.

From March to September, the Northern Hemisphere faces the Sun. It receives more light and heat than the South, and on its continents it is gradually summer season when the day is longer than the night. Then the Earth, without changing its angle of inclination, changes its position, and now the continents of the Southern Hemisphere are facing the Sun, and the traditionally cold winter months in our country are hot. At this time, winter returns to the countries of the Northern Hemisphere.

So, our planet makes a full revolution around the Sun during the year, during this period of time its different parts manage to heat up or cool down, depending on the amount of heat received by them.

Climate zones of the Earth

Regions of our planet differ in their climate. The presence of climate zones is associated with uneven heating of the surface of the globe by the Sun and varying degrees of distribution of precipitation on it.

Astronomical seasons do not always coincide with the climatic seasons of the continents. For example, in one region snow falls in winter, and It is raining in summer, in another there will be no precipitation at all for a long period of time, and long long rains begin at a certain point in the year.

Types of climate zones of the Earth:

• Equatorial. In spring and autumn in the regions of this belt there is a dry season, with heavy rains in summer and winter.

• Tropical. The weather is hot throughout the year; heavy rainfall is observed only during the cold rainy season.

• Moderate(includes Western European countries, Central part Russia). In autumn and winter there is a lot of precipitation, snow falls on the ground, in summer and spring it is warm and relatively dry.

• Arctic and Antarctica. This climate zone is characterized by constant temperature: it always stays below zero. The change of polar night and day means a change of seasons.

Today, in one day, changing the cold season to a warm one and getting from winter to hot summer is very simple, you just need to buy a plane ticket. Many travel lovers take advantage of this feature of nature.

How do the seasons change?

These educational materials will help your child quickly learn and remember the names of the seasons and months. Download and print the calendar picture; you will need to hang it in a visible place so that the child often sees the calendar with his eyes during the day. He will involuntarily scroll through his memory the names of the seasons, winter, spring, summer and autumn months.

Naturally, before this it is necessary to familiarize the child with these seasons. Start your story with winter. Be sure to tell the signs of what is happening in nature at this time of year, what the weather is like, so that the child can feel and vividly imagine the full picture of the season.

in winter the day is short. The sun is low and warms weakly. Snow falls. Cold. People wear winter clothes. In winter we celebrate everyone's favorite holiday - New Year.

in spring the day is getting longer. The sun is warming better. It is getting warmer. Snow is melting. Streams are flowing. Leaves appear on the trees. Grass begins to grow. Flowers are blooming. They're arriving migratory birds. People wear demi-season clothes. The most famous spring holidays are March 8 and May Day.

In summer the sun is high, shining brightly, warming well. Costs hot weather. Flowers bloom and berries appear. People wear summer clothes. You can swim in natural reservoirs and sunbathe.

in autumn the day is getting shorter. The sun is lower. It's getting colder. The harvest of vegetables and fruits is ripe. Leaves are falling from the trees. Migratory birds fly south. It rains often. People wear warm clothes. The most famous autumn holiday- day of knowledge.

And winter is coming again...

Do not forget to discuss the very concept of “seasons”, what a year is. Children often confuse “season”, “time of day”, “week”, “month” and simply “time”, immediately distinguish between these concepts. Riddles will help with this:

There is a tree in the royal garden. On one side the flowers bloom, on the other the leaves fall, on the third the fruits ripen, on the fourth the branches are pruned. What kind of tree is this? (year)

These birds fly in a line,
And they won't come back anymore.
There are seven birds in every flock,
You all know them! (Days of the week.)

twelve brothers
They wander after each other,
But they don't overtake each other. (Months.)

The bridge stretches
For seven miles,
And at the end of the bridge -
Golden Mile. (A week.)

They come every year
To visit us:
One gray-haired
Another young one
The third gallops
And the fourth one is crying. (Seasons.)

Invite your child to come up with his own story about the seasons.

Don't forget to tell your child that a year consists of 12 months, and each season has 3 months.

Calendar seasons

Further knowledge can be deepened by dividing what happens in nature into months, as shown in the pictures. Ask your child questions: “When do the leaves fall from the trees?”, “When will we go swimming in the river?” and the like in order to retain the material well in memory.

There are calendars on sale with a moving hand for studying the seasons and months of the year. You can make such a calendar with your own hands by simply printing out a drawing and attaching a cardboard arrow.

Cards, coloring pages and riddles will help children consolidate their knowledge about the seasons.

Cards

You need to cut along the lines.

IN kindergarten or at home you can make an applique from colored paper on the theme of the seasons. Sample:

How to learn the names of the months with your child

A simple poem will help you remember the months:

January was walking through the snowdrifts, the king of all winter frosts!
February caught up with him - he lost his shawl from the blizzard.

March came running for his shift and the ringing rang: “Spring, let’s start!”
April sailed along the streams, he carried drops in his pocket.

The leaves of May rustled: “Take off your warm jacket!”
The dandelion carried June. Do you want a miracle? Just blow!

And in July, and in July we had a holiday at sea!
August was buzzing with bees and sitting like a mushroom in the forest.

In golden September we forgot about the heat!
The wind blew in October: let's pick up yellow leaves!

November froze us and threw the first snow on the ground.
December is upon us, ending a long year!

(c) Irina Gurina

Or another poem:

We have learned the names of the months and their order, now you can tell your child the secret of how to determine/count the number of days in a month using their fists :)

Don't forget to tell us about leap year!

Thirty days are always in September,
In April, June and November.
One day more in other months,
Only February doesn’t want to catch up.
There are only twenty-eight days in it,

The concept of "Seasons"

Throughout the year, our planet experiences seasonal changes in nature. Due to the inclination of the earth's axis to the orbital plane at an angle of $66$ degrees and rotation in orbit around the Sun, the planet experiences a change of seasons. There are four seasons on Earth – spring, summer, autumn, winter. The tilt of the earth's axis and its constant direction in space lead to the fact that the Northern and Southern hemispheres are not illuminated equally during the same period of the year. In the Northern Hemisphere of the planet, the astronomical beginning of the seasons coincides with the moment when the Sun passes through the vernal equinox - March 21, the summer solstice - June 22, autumn equinox–$23$ September and period winter solstice– $22$ December. Thus, it turns out that the apparent path of the Sun’s movement across the celestial sphere is divided by these points into sectors of 90 degrees.

Definition 1

The period during which the Sun passes one of these sectors is called time of year.

The duration of the seasons from an astronomical point of view is also different:

• Duration of spring – $92.8$ days;
• Duration of summer – $93.6$ days;
• Duration of autumn – $89.8$ days;
• Duration of winter – $89.0$ days.

Seasons are characterized by certain average temperatures.

Note 1

Autumn in the Southern Hemisphere and spring in the Northern Hemisphere begin when the Sun passes through the initial circle of declination. At this time, the right ascension of the Sun will be zero ( the vernal equinox). When the sun's right ascension is $90$ degrees ( summer solstice), then winter comes in the Southern Hemisphere, and summer comes in the Northern Hemisphere. With the onset of the autumn equinox, the sun's right ascension is $180$ degrees, at which time spring comes to the Southern Hemisphere and autumn to the Northern Hemisphere. With the onset of the winter solstice, winter comes to the Northern Hemisphere and summer to the Southern Hemisphere.

Seasons in the Northern Hemisphere

The sun sends a lot of heat to the Earth, thanks to which life exists. However, the heat reaching the Earth's surface will be different in different regions because it is distributed unevenly. Naturally, winter is colder than summer everywhere. The reason is that the earth's axis (an imaginary line) that connects the North and South poles is inclined to the plane of the earth's equator at an angle of $66$ degrees. Due to the tilt, the Earth, rotating around the Sun, turns to it alternately with either the Northern or Southern Hemisphere. Tilt of falling on earth's surface sunlight changes throughout the year - in winter it will be more, and in summer - less. More vertical beams carry more energy.

Definition 2

Term "Climate" translated from Greek means “slope”. In the Northern Hemisphere, winter comes when the planet, as it were, “turns away” from the Sun. At this time, the disk of the Sun rises lower and lower above the horizon, and the rays become flatter and less hot. The middle latitudes of the northern hemisphere are clearly divided into two main, opposite in nature, seasons - summer and winter. They differ from each other in temperatures, the difference between which is $20-30$ degrees. In continental regions this difference is even greater; in Siberia, for example, it is up to $50$ degrees.

The main climatic zones of the Northern Hemisphere are the Arctic, temperate and tropical. Atlantic coast North America And Western Europe They lie in a temperate oceanic climate zone, so the bulk of precipitation occurs in autumn and the first half of winter. Sporadic rains along with cyclones begin in spring and summer. In the Arctic zone, the change of seasons is expressed in the alternation of polar day and polar night. There is little seasonal variation in precipitation and temperatures remain below freezing. Continental part temperate zone – Eastern Europe and Southern Siberia - have drier autumns and winters, and the summer months are the wettest. On Far East, which is in the area monsoon climate, precipitation falls in the form of intense showers exclusively in summer. The sun is at its zenith on the summer and winter solstices, and these are the tropical latitudes of the Northern and Southern Hemispheres. The atmosphere here is transparent, the air masses are dry with very high temperature, which over land can reach highest value on Earth $+58$ degrees. In winter, the temperature cools quickly and frosts are possible on the soil. Sharp contrasts are associated with precipitation. The tropical desert climate region is formed in the west and in the interior of the continents. Here, with downward air currents, less than $100$ mm of precipitation may fall per year. The eastern part of the tropical belt is located in a humid region with tropical marine air masses coming from the oceans, so several thousand millimeters of precipitation falls throughout the year.

Seasons in the Southern Hemisphere

In the Southern Hemisphere, the belt change occurs from the equator to the south. The zones are repeated and the main ones are tropical, temperate, Antarctic. Only equatorial belt, located on either side of the equator will be one. Here, throughout the year, day is equal to night and the midday height of the Sun above the horizon does not change. The air temperature is almost constant. There are no seasons here, this is the land of “eternal summer”.

The planet's climates and seasons would be completely different if the earth's axis were not tilted to the orbital plane. Essentially, there would be only two seasons, smoothly transitioning into each other - eternal winter in the polar region and eternal summer in the equatorial region. Under the same climate, life on Earth would be more monotonous.

Reasons for differences in seasons

Seasonal changes in the state of nature have their own causes, which are divided into direct and indirect causes. Direct reasons include geographical ones:

• Seasonal changes are associated with the length of daylight hours - days in summer are long and nights are short. In winter, their ratio is reversed;

Seasonal changes are associated with the midday height of the Sun above the horizon.

In temperate latitudes in summer at noon the Sun is closer to the zenith, and the same amount of solar radiation is distributed over a smaller area of ​​the earth's surface.

The length of the path of the Sun's rays in the atmosphere affects the degree of their absorption.

The lower the Sun is above the horizon, the less heat and light it provides.

Indirect astronomical reasons are:

• The spherical shape of the Earth;
• Parallelism of sun rays;
• Rotation of the Earth around its axis;
• Movement of the Earth around the Sun;

Note 3

The main astronomical reason for the change of seasons is related to the tilt of the earth's axis and the movement of the earth around the sun.

Spring has come. The gray and dull snow disappeared from the fields, and the sun became warmer and more gentle. Nature awakens: the first greenery begins to emerge, the buds on the trees swell and bloom, migratory birds return, and living creatures emerge from their holes and nests. Soon summer, autumn, winter will come and spring will come again. Seasons change on our planet from year to year.

But what ensures these cyclical changes in nature? The main reason for the change of seasons is the tilt of the axis of our planet relative to the ecliptic plane, i.e. the plane of rotation of the Earth around the Sun. The Earth's axis is tilted from the ecliptic plane by 23.44°. If this angle were equal to zero, the seasons would never change on the planet, the length of day and night would be the same, and the sun would rise above the horizon to the same height throughout the year.

Do seasons change on other planets in the solar system?

Mercury

If we take into account only that indicator that has a decisive influence on the formation of the seasons on Earth, the tilt of the rotation axis, then Mercury should not have the seasons we are accustomed to. However, Mercury moves in a very elongated orbit, approaching the Sun at perihelion by 46 million km and moving away by 70 million km at aphelion, which has a significant influence on the formation of Mercury's weather. Being at a short distance from the Sun, the illuminated side of Mercury heats up to an average of +300°C (maximum: +427°C) and the Mercury summer begins. In the far part of the orbit, winter sets in; even during the day at this time the temperature does not rise above 107°C, and at night it drops to -193°C.

Dawn on Mercury occurs only once every two years (every 176 days), but it is the hottest dawn in the entire system.

At the same time, almost no sunlight reaches the poles of Mercury due to the minimal inclination of the rotation axis to the ecliptic plane (0.01°). In these dark and cold regions, polar ice caps have been discovered, although they are only 2 meters thick.

Interestingly, a day (175.94 Earth days) on Mercury lasts twice as long as a year (87.97 Earth days).

On Venus, like on Mercury, there is also no change of seasons. Venus' rotation axis angle is an impressive 177°, in other words, this planet has an inverted orientation, and the actual inclination angle is only 3°. Orbital eccentricity, i.e. its degree of deviation from the circle is extremely small (0.01) and therefore does not make any adjustments to the weather. All year round A hot summer reigns on the surface of the planet: average temperature exceeds +400°C.

Venus is sultry all year round, with an average temperature of about +400°C.

Mars

Mars is similar to our planet in many ways. The inclination of the axis of rotation of Mars relative to the plane of its orbit is 25.2°, which is only slightly greater than that of Earth. The eccentricity of the Red Planet's orbit is also slightly larger. As a result, the Martian climate is slightly more seasonal, meaning the differences (especially in temperature) between the different seasons are more pronounced.

Another one interesting feature Martian seasons is that they differ significantly in different hemispheres of the planet. So in southern hemisphere hot summers and Cold winter, while in the north there are no such contrasts - both summer and winter here are mild.

Jupiter

The axis of rotation of the giant planet is inclined by only 3.13° relative to the orbital plane, and the degree of deviation of the orbit itself from the circle is also minimal (0.05). In other words, the climate here is not seasonal and is constant throughout the year.

Saturn

The tilt of Saturn's rotation axis is 29°, so the change of seasons on this planet is characterized by more pronounced differences in the amount of sunlight, and therefore temperature, than on Earth. Each season - be it summer or autumn - lasts about 7 years on the giant planet. Depending on the time of year, Saturn can change its color. Eight years ago, when Cassini first approached the planet, it was winter in the northern hemisphere and this part of Saturn had a blue tint. Today the south is painted blue - winter has arrived there. According to astronomers, this phenomenon occurs due to the intensity of ultraviolet radiation - in winter it decreases, with the arrival of summer it increases.

Winter on Saturn's southern hemisphere. The blue haze that covers the south pole of the planet is a direct consequence of the drop in temperature, i.e. the arrival of winter. 10 years ago, in 2004, exactly the same blue fog enveloped North Pole gas giant.

Uranus

The angle of inclination of the planet's rotation axis is 97.86° - in other words, Uranus lies on its side slightly upside down. This factor explains the rather specific change of seasons. During solstices, only one of the planet's poles faces the Sun. The change of day and night that is familiar to us is characteristic only of the equator; the remaining parts of Uranus are under the cover of the polar day or polar night for 42 Earth years.

Voyager 2 photograph of Uranus

At the pole facing the Sun, dramatic changes occur: the temperature increases significantly, the upper layers of the atmosphere begin to slowly acquire bright colors, replacing a pale blue hue, the speed of winds and the number of clouds increase.

Neptune

On Neptune, the rotation axis is tilted by 30°, so the seasons here are similar to those on Earth, but the distance of the planet from the Sun makes its own adjustments. A year on Neptune is almost 165 Earth years, therefore each season lasts, no more and no less, 41 years! Summer began in the southern hemisphere in 2005 and will last until 2046.

The reasons for the change of seasons become relevant for each person. Already in childhood, the child begins to ask questions. Why does winter come? What is happening to our planet? Why in different countries different climate?

The first and main explanation is to create optimal climatic conditions for human habitation. Temperatures across the planet are becoming comfortable for living.

What does astronomy say about the changing seasons?

Spring, summer, autumn, winter are eternal and unchangeable natural phenomena. The reason for such natural phenomena becomes the movement of the globe in outer space. The Earth moves in a conventional orbit, which has the shape of an elongated circle.

Unfortunately, many people still live by stereotypes school programs, where the explanation for why winter comes was the approach and distance of the planet from the Sun during its movement.

Astronomers have long refuted this theory and claim that the change occurs due to the axis of rotation of the planet. It is tilted 23 degrees, so Sun rays unevenly heat different parts of the Earth at different times.

Why is it very cold in winter?

The Earth's orbit around the sun takes 1 year or 365 days. During the entire movement, the planet rotates along its conventional axis, which becomes

When the north turns towards the Sun, it receives maximum amount rays, while in the south such rays will fall “casually” onto the earth’s surface.

Autumn and winter are those periods of time when the Earth is at its maximum distance from the Sun. The day becomes short, and the sun shines, but does not warm.

The minimum amount of heat from the celestial body is explained simply. The rays fall to the surface obliquely, the sun does not rise high above the horizon, so the warming of the air will be slow.

What happens to air masses in winter?

When the air temperature drops, evaporation decreases and air humidity changes. When the concentration of water vapor in the atmosphere decreases, the ability to trap heat on the Earth's surface is also reduced to a minimum.

The transparent atmospheric mass of air is not capable of absorbing infrared radiation, which heats the air and the surface of the earth. Why is it cold in winter? Only because the surface and air cannot retain heat, which is already supplied in minimal quantities.

What's the sun like in winter?

It is extremely important to explain to children about the sun and its changes in winter. Here the emphasis should be placed on the fact that the Sun is a huge, hot star around which a large number of planets revolve.

The sun has an enormous temperature; no person or aircraft can approach it, as it will simply melt and destroy them.

Thanks to solar energy and rays, life is possible on planet Earth: trees grow, animals and people live. Without the sun's heat, all living things will die in a short period of time.

Solar energy and rays do not heat so intensely in winter, but can bring more harm skin. This feature has a logical explanation: the entire surface of the planet, which should reflect the rays, is light and mirror-like, since it is covered with snow. The human body cannot reflect; it receives ultraviolet rays and is actively saturated with them. Doctors emphasize that tanning in winter is more dangerous than in summer. The skin is oversaturated with ultraviolet radiation from the sun and can even get burned.

Why winter comes can be explained to children and adults by knowing the basics of astronomy. But what does it contain? winter nature, which Interesting Facts Are winter known to science and people?

• Snowflakes. Scientists have repeatedly studied snowflakes that fall to the surface of the earth. Such work requires special training, equipment and scrupulousness. The discovery for people was that snowflakes can have 7 types: star crystals, needles, columns, columns with tips, transparent dendrites, snowflakes of irregular shape.

• Speed ​​of snow mass. For many, snow is a soft, airy substance, but large quantities snow mass, it can descend from the surface of the earth in the form of an avalanche. The minimum speed of such an avalanche is 80 km/h, the maximum is 360 km/h. A huge mass of snow destroys everything in its path. If a person falls under an avalanche, he dies due to the enormous weight or lack of oxygen.
• For most of the world's population, the question of why winter comes is not relevant. They don’t even know that there may be a sharp change in air temperature, the readings will drop below 0, and it will snow. In some kingdoms of hot countries they organize games on artificial snow from sugar to amuse his subjects.

Why does winter come? Every child asks this question sooner or later. Using the material presented, every parent will be able to answer this question easily and interestingly.