Most people are so used to the fact that the seasons are something settled that they don't even think about why they change. Moreover, many do not come up with the idea that there may be not 4, but more. Let's talk about all this in detail, but succinctly.
How many times are there in a year
It would seem that the question is just childish. 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 into 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, large coastline, frequent weather changes - all this forced the ancient Indians to come up with a completely new system that met the requirements of local residents.
Even more surprising may seem the system of the Saami - the indigenous inhabitants of Finland and the surrounding regions. Here the calendar consists of as many as eightseasons!
So, as you can see, the question of how many seasons there are, in different parts of the Earth, you can get quite different answers.
How is the year divided into seasons
Let's look at the European system that operates in our country, and is also the most common throughout the world.
True, and here everything is not too clear. For example, in our country, the seasons are rigidly 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 starts 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 summer-like than the last two weeks of May. Therefore, some people agree with the statement that the old calendar (Julian), abolished after the Revolution of 1917, was more accurate and reliable.
However, in other countries of the Northern Hemisphere, where the Gregorian calendar is also used, the problem is solved in a very original way. The fact is that here the seasons are not the 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 really more reliable - after all, the climate on Earth depends primarily on the Sun.
Thus, inIn 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 on March 22 - after the spring equinox, when the day became a few seconds, but longer than the night.
Why the seasons change
Another seemingly fairly simple question that not everyone can answer, even if they have completed secondary education.
It's about the rotation of the Earth. As you know, it rotates around its axis, making a revolution in a little more than 24 hours. And so the days come. But the planet also revolves around the sun. Because of this, the season changes. Let's talk about this mechanism in more detail.
Imagine the circle that the Earth describes as it revolves around the Sun. Now imagine the axis around which the Earth rotates in a day. So, it turned out that this axis is not at all perpendicular to the circle. Indeed, in this case, the weather on Earth would be the same all year round - the changes of the seasons would not exist.
But it's not. As scientists managed to calculate, the angle between the axis and the circle is approximately 66.6 degrees. But this is not a constant - this angle has changed many times in the past and will certainly change many times in the future. Of course, even the slightest change in slope leads to drastic changes in climate.
So, as already mentioned, the sun's rays fall on the Earth not under direct rays. Even for the equator, which warms up most actively on the planet, this bringscertain changes (we will discuss them below), and for the Northern and Southern hemispheres the difference becomes simply huge. 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, more precisely, they fall at such an angle that most of the heat is simply reflected. Of course, this leads to hot summers and cold winters.
This can also explain the polar night and day - while one pole is illuminated day and night, the other does not receive sunlight and heat at all.
Summer in brief
According to many people (especially, of course, children), summer 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 is at this time that nature appears in full glory - green forests, flowering fields.
However, closer to the equator, everything changes dramatically, especially in regions with a sharply continental climate. The heat here becomes unbearable, there is practically no precipitation, the winds are burning, blowing out the last moisture. Surviving in such conditions is really difficult - you either need not to go outside during the peaks of the heat, or have such a habit instilled from childhood.
What is autumn
What time of year does summer end? Any childwithout hesitation will answer - autumn. And many will add that this is the saddest time. Summer is over, winter is coming - for many people this causes bouts of nostalgia and even melancholy. Autumn lasts from September 1 to December 31, or from September 23 to December 21.
By this time, nature brings abundant fruits and prepares for winter. People are harvesting, storing supplies that will allow them to survive the cold half a year. Foliage on trees (except evergreens) turns yellow or reddens and falls off. Many birds and even some animals migrate to warmer climes, where they will be able to get food, easily survive the cold season.
In some regions of the earth, it is the borderline between wild summer heat and fierce winter rains - at this time, some plants and animals have time to live a full life cycle.
A little about winter
If we talk about the seasons, this is the coldest. It lasts according to 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 turned to the Sun at such an angle that the star closest to us actively shines, but practically does not heat. Yes, and daylight hours are significantly reduced - this is also a consequence of the significant angle of inclination of the earth's axis.
It snows in the northern regions. In some places, it lies for as long as half a year, while in others it falls out in a matter of hours, only to fall out again after a few days or weeks.
Toward the equator, heavy rains fall during these months. Moisture-loving plants, fish and reptiles are in a hurry to live a whole era of their lives until the blessed water evaporates.
Features of spring
Finally, we move on to spring. Perhaps most people, when asked what time of the year is the most romantic, will name it. No wonder - spring is coming, nature is awakening, and a person seems to be waking up after a long winter, feeling renewed. Hormones enter the blood in an increased amount, which changes both the well-being and behavior of people.
Lasts according to the calendar from March 1 to May 31. According to the astronomical cycle - from March 21 to June 21.
In regions with a temperate climate, at this time, nature is awakening, preparing for a difficult summer. And in others, on the contrary, animals and plants that actively lived with an abundance of moisture and the absence of too high temperatures are preparing for hibernation or minimal activity - it is better to endure the hellish heat in this state.
What about in the Southern Hemisphere?
As mentioned above, the Earth is facing the Sun with one hemisphere - either the Southern or the Northern. As a result, the climate on them is very different. Surprisingly, for residents of Argentina, Brazil, Mozambique, Australia, the hottest months are January and February. But in July and August, they wrap up warmer to survive the cold season.
Spring in the Northern Hemisphere corresponds to autumn in the Southern and vice versa. Surprising but true.
Conclusion
This article comes to an end. Now you know that the seasons are a serious stage in the life of man and nature. And you can also easily talk about how and why spring replaces winter, and summer invariably comes to autumn.
