Most people are so used to the fact that the seasons are something well-established that they don’t even think about why they are changing. Moreover, the idea that there may be not 4, but more of them does not come to many. We will tell about all this in detail, but capaciously.
How many times a year
It would seem - the question is just for children. After all, everyone knows that there are exactly four seasons: spring, summer, autumn and winter. However, this is obvious to any person in our country, Europe and America. But there are other options for dividing the year into seasons.
For example, in India, where the year is also divided by 12 months, there are as many as six seasons! True, each of them consists of only two months. This is easy to explain - proximity to the equator, a large coastline, a frequent change of weather - all this forced the ancient Indians to come up with a completely new system that meets the requirements of local residents.
Even more surprising may be the Sami system - the indigenous people of Finland and the surrounding regions. Here the calendar consists of as many as eight seasons!
So, as you can see, to the question how many seasons there are, quite different answers can be received at different points on the Earth.
How is a year divided into seasons?
Let's look at the European system, which operates in our country, and is also the most common in the whole world.
True, here everything is not too clear. For example, in our country, the seasons are tightly tied to the calendar - for simplicity and convenience. But the weather is not going to obey the conventions invented by man. Therefore, the astronomical time of the year does not always coincide with the calendar time. For example, winter begins on December 1 and ends on February 28 (or 29). For the summer, the frames are also set quite clear - from June 1 to August 31. Everything is simple and clear. However, many will agree that the first two weeks of September are usually much more like summer than the last two weeks of May. Therefore, some people agree with the statement that the old calendar (Julian), canceled after the 1917 Revolution, was more accurate and reliable.
However, in other countries of the Northern Hemisphere, which also uses the Gregorian calendar, the problem is solved in a very original way. The fact is that here the seasons are not dates on the calendar, but the position of the stars in the sky. In other words, the new season begins not on the first day of the month, as people decided, but on the day of the solar equinox or solstice. The binding is indeed more reliable - because the climate on Earth depends primarily on the Sun.
Thus, in some countries it is believed that summer begins on June 22, autumn on September 23, winter on December 22, and spring, respectively, on March 21. It is no coincidence that once in Russia the New Year was celebrated precisely on March 22 - after the vernal equinox, when the day became a few seconds, but longer than night.
Why are the seasons changing?
Another seemingly fairly simple question that not every person can answer, even if he received secondary education.
The thing is the rotation of the Earth. As you know, it rotates around its axis, making a revolution of a little more than 24 hours. So there is a day. But the planet also makes a revolution around the sun. Because of this, the time of year changes. We will talk about this mechanism in more detail.
Imagine the circle that the earth describes, revolving around the sun. Now imagine the axis around which the Earth rotates in a day. So, it turned out that these axis are not at all perpendicular to the circle. Indeed, in this case, the weather would be the same on the Earth all year round - there would be no change of seasons.
But this is not so. As scientists were able to calculate, the angle between the axis and the circle is approximately 66.6 degrees. But this is not a constant - this angle in the past has changed more than once and will surely change many times in the future. Of course, even the slightest change in slope leads to dramatic changes in climate.
So, as already mentioned, the sun's rays do not fall to the earth under direct rays. Even for the equator, warmed up most actively on the planet, this brings certain changes (we will discuss them below), and for the Northern and Southern hemispheres the difference becomes simply enormous. On one of them, the sun's rays fall under relatively direct rays, which allows them to be absorbed by the earth and water, which are actively heated. But at the same time, the sun's rays almost do not fall on the other hemisphere, or rather, fall at such an angle that most of the heat is simply reflected. Of course, this leads to hot summers and cold winters.
The same can explain the polar night and day - while one pole is illuminated day and night, the other does not receive sunlight or heat at all.
Briefly about summer
According to many people (especially, naturally, children), it is summer that is the best time of the year. But the climate does not always agree with this conclusion.
Summer lasts in our country from June 1 to August 31, according to another European system - from June 22 to September 22. In temperate latitudes, it is associated with the highest temperature and, as a rule, heavy rainfall. It was at this time that nature appeared in full glory - green forests, flowering fields.
However, closer to the equator, everything changes dramatically, especially in regions with sharply continental climate. The heat here becomes unbearable, almost no precipitation, winds burning, blowing the last moisture. Surviving in such conditions is really difficult - you need to either not go outside in the heat peaks, or have such a habit instilled from childhood.
What is autumn
What time of year does summer end? Any child will answer without hesitation - autumn. And many will add that this is the most sad time. Summer has passed, winter is nearing - for many people this causes attacks of nostalgia and even melancholy. Autumn lasts from September 1 to December 31, or from September 23 to December 21.
By this time, nature is bearing abundant fruits and is preparing for winter. People harvest, stockpile supplies that will survive the cold six months. Foliage on trees (except evergreen) turns yellow or red and falls. Many birds and even some animals migrate to warmer places, where it will be possible to get food, it is easy to survive the cold season.
In some regions of the world, it is a borderline state between wild summer heat and fierce winter rains - at this time some plants and animals manage to live the full life cycle.
A little bit about winter
If we talk about the seasons, this is the coldest. It lasts on the calendar from December 1 to February 28 (in a leap year to February 29). And by astronomical standards - from December 22 to March 20.
At this time, one hemisphere of the Earth is facing the Sun at such an angle that the star closest to us is actively shining, but it practically does not warm. Yes, and daylight hours are significantly reduced - this is also a consequence of the significant angle of inclination of the earth's axis.
Snow falls in the northern regions. In some places it lies for half a year, while in others it falls out in a matter of hours, so that after a few days or weeks it falls out again.
Closer to the equator these months are heavy rains. Moisturizing plants, fish and reptiles are in a hurry to live an entire era from their lives until the fertile water evaporates.
Spring features
Finally, move on to the spring. Perhaps most people, when asked what season is the most romantic, will call it her. No wonder - spring is coming , nature is awakening, and it is as if a person wakes up after a long winter, feels updated. Hormones enter the bloodstream in an increased amount, which changes both the well-being and behavior of people.
It lasts on the calendar from March 1 to May 31. In the astronomical cycle, from March 21 to June 21.
In regions with a temperate climate at this time, nature awakens, prepares for a difficult summer. And in others, on the contrary, animals and plants that were actively living with plenty of moisture and the absence of too high temperatures are preparing for hibernation or minimal activity - it is better to endure the infernal heat in this state.
And what about the southern hemisphere?
As mentioned above, the Earth faces the Sun in one hemisphere - then the South, then the North. As a result, the climate on them is very different. Surprisingly, for the residents of Argentina, Brazil, Mozambique, Australia, the hottest months are January and February. But in July and August they wrap themselves warmer to survive the cold season.
Spring in the Northern Hemisphere corresponds to autumn in the Southern Hemisphere and vice versa. Surprisingly, a fact.
Conclusion
On this article comes to an end. Now you know that the seasons are a serious stage in the life of man and nature. And also you can easily talk about how and why spring is replaced by winter, and summer invariably comes to fall.