Have you ever wondered why some people can enjoy the sun, while others must wear coats and gloves? This is thanks to the seasons. Here you will discover what are the seasons of the year?, what are the dates of these four seasons?, their differences according to each country and more.
The changes that occur in the climate during different times of the year are known as seasons. That is to say, they are the cycles of time in which a year is segmented and that have a longer period of time, they are characterized according to certain alterations in the Temperature and Humidity, such as wind, temperature, rain, among others.
The term season is a consequence of the combination of the Latin words station y onis, which would translate as a place of permanence. In which the properties of the climate remain unchanged, during those periods of time.
Why do the seasons occur?
The seasons occur according to the way the earth rotates around the sun, as well as the tilt of its axis. Although they do not perceive it, the planet Earth is constantly in movement, these displacements are the one of rotation with which you can notice how it goes from day to night and the one of translation, which it does around the King Star and allows you to see the run through the months of the year.
Due to the tilt of the earth on its axis, along the path of translation, some regions of the planet receive different intensities of sunlight, depending on their proximity to it. For example, if the southern part of the earth is tilted towards the sun, then all of that area will be summer, while the other part will undoubtedly be winter.
Periods of climatic seasons
It is quite frequent that they can associate the word seasons, to the four phases climatic that occur in the temperate regions of the northern and southern parts of the earth.
These cycles are those of spring, summer, autumn and winter, which have an extension time of approximately ninety days each season.
But these marked climatological differences occur uniformly in all areas of the earth, that will also depend on where you are geographically located, such as if you are located in Ecuador, the weather conditions will not change so radically, they can be observed two periods, one of rain and the other of drought.
Similarly, it happens at the poles of the earth, both North and South. In which two periods are distinguished, which are characterized by the presence of sunlight or not, here they can only notice the presence of summer and winter periods, which last six months each.
Seasons of the year and their origin
By virtue of the movement of translation that the earth makes around the sun and according to the inclination that it carries during that journey, it is that the stationary cycles occur during the year.
According to the plane of inclination of the earth, four positions are produced that are mentioned below:
- Equinoxes that occur, one on March 21 and the other on September 23.
- Solstices, there are also two and they are on June 21 and another on December 21.
These events individually, start each of the four seasons, according to the inclination of the earth, the duration of the days and nights will be appreciated, in each of the seasons.
This is thanks to the fact that the earth does not make this journey constantly, so, thanks to the elliptical shape of its orbit, there is a difference in the duration of each season.
Next, the information on the elements of astronomy that are related to the seasons and how they act on each of them will be expanded.
Before you can delve deeper into the topic of how astronomy affects temperatures and changes in the climate, it is interesting that you know what are the characteristics that differentiate each of the seasons.
How are the seasons different?
The characteristics by which the seasons can be differentiated will depend on the climate and the ecology of the biosphere of each of the zones.
Thus, spring is characterized by the fact that the duration of the day is greater than the night, that is, the presence of sunlight lasts more hours. The temperature begins to increase and the foliage of the plants begins its regrowth process.
During the summer, the sunlight is still greater than the night, but a slight decrease in the number of hours of sunshine is beginning to be noticed. With high temperatures and the foliage of the plants is in full bloom of its vegetative cycle.
The autumn cycle and the hours of the day are getting shorter, with a marked decrease in internal energies, it is also common for the leaves of the plants to lose vitality and begin to fall. Characteristic to see the fields covered with dry leaves that have fallen.
In winter, the days have less sunlight, and each day the light progresses, it will be less. Low temperatures characterize this stage and the trees completely lose their foliage, to enter a dormant stage that allows them to survive the harsh climate.
Astronomical fundamentals that define the seasons
The astronomical principles and the shape of the earth, which are closely linked to the seasons of the year, are: the movement of the earth, the fixed axial tilt and the shape of the planet, which can be expressed according to latitude.
Translation
The earth moves around the sun, describing an orbit in the form of an ellipse, while the sun is located at one of its foci. It is for this reason that the separation between our planet and the sun varies throughout the year.
It is at the beginning of the month of July, that the earth transits through a place in the orbit, which has the name of Aphelio. This location is more than 150 million kilometers away, being the most distant place on the planet with respect to the sun.
For the month of January, the planet earth moves to the orbital location called Perihelion, which is more than 140 million kilometers away from the King Star, becoming the smallest distance that separates these two elements. of the cosmos. Being located at Perihelion, the earth receives more than 5% of solar energy.
Although the displacement due to the translation of the earth and its elliptical shape of the orbit, would be responsible for the changes in the seasons in the southern hemisphere, the disparity in the amount of energy received by the northern hemisphere , is imperceptible.
Latitude
The changes in the seasons that the earth suffers are linked to the angle of incidence of the sun's rays on it. Thus, the sun's rays will have to strike perpendicularly, that is, at an angle of ninety degrees (90°), the energy will affect a smaller surface but with greater intensity. Whereas, if the angle is other than ninety degrees (90°), the surface touched will be larger, but the intensity decreases considerably.
Due to the fact that the earth has a shape very similar to that of a sphere, the incidence of the sun's rays is modified as they can approach or move away from the equator.
When it is in Equinox, the sun hits the earth perpendicularly at the Equator. If they were to move within thirty (30°) degrees, either north or south, the sun would strike at an angle of approximately sixty degrees (60°).
If the earth did not have this rotational inclination on its axis, the seasons could not occur, the solar incidence being of equal intensity, throughout the year.
Inclination angle
The earth, in addition to the movement of translation with respect to the sun, traces an elliptical figure on the plane. Also, it can rotate on its own axis, which is an imaginary line, which crosses the mass of the earth where the north and south poles can be located.
If they are located perpendicular to this axis of rotation, they find a line that establishes the Equator and divides the earth into two hemispheres: the northern hemisphere and the southern hemisphere.
This axis maintains the same inclination throughout the year. Consequently, it always points in the same direction. Due to this, when the earth transits in its orbit, the angle that the sun's rays describe with respect to the angle of the earth, are matched.
It means that the incidence of the sun's rays changes continuously as it moves across the earth's surface. If the angle is greater in a certain region, it will be summer there.
As it decreases, it will go to autumn, then to winter, which is the time of least incidence of sunlight. This percentage of incidence will increase again, which generates spring and with this they will have been completed the four Seasons of the year.
The cycle will be repeated again at the time of completing another return to the sun's orbit, repeating itself as many times as the sun and the earth exist.
What are the seasons of the year?
As you know, the year consists of 365 days and the year is divided into seasons that are the ones that impose the climate conditions of each zone.
It should be taken into account that four periods are generated during the year, within which certain conditions are favored that remain stable for a period of approximately ninety days and each of these times is called:
- Spring
- Summer
- Fall
- Winter
Each of them will be referenced below:
Spring
It begins in the northern hemisphere, from the beginning of the March equinox, while in the southern hemisphere, it begins in the month of September. Having a duration of almost ninety-three days in the north and ninety days in the south.
Their days and nights have a fairly similar duration. This period ends, when the earth's axis tilts towards the solstices, from the boreal zone in the month of June and from the southern part in the month of December.
The characteristic climate of this season remains between the months of March and June for the northern hemisphere, while in the southern hemisphere it comprises the months of September and November.
Summer
It begins from the June solstice, in the northern hemisphere of the earth. It is characterized by having the day with the greatest presence of sunlight throughout the year, it is throughout this season that you can see that the days are longer, compared to the duration of the nights.
The summer season ends with the arrival of the September equinox, lasting almost ninety-four days, in the northern part of the earth.
In the southern hemisphere, the summer season begins with the December solstice, making the days shorter, and ends with the arrival of the March equinox. The duration of summer in the southern hemisphere is almost 90 days and the nights are the longest of the year.
According to meteorology, summer runs between the months of June and August for the boreal zone of the earth and from the month of December to the month of February, in the southern part of the planet.
Fall
It has its start from the equinox of September, in the northern hemisphere. The autumn season ends, when the December solstice begins and lasts approximately 90 days.
In the southern hemisphere, the season starts at the beginning of the March equinox, ending with the June solstice. It lasts ninety-three days.
In the autumn season, both the day and the night have a very similar duration, it is the same as saying that each of the periods is approximately twelve hours long.
The characteristic climate of this season goes to the northern hemisphere between the months of September and November, while in the southern hemisphere it comprises the months of April and May.
Winter
This stationary period originates from the effect of the December solstice, culminating the winter season with the March equinox, in the northern hemisphere. It has a duration of 90 days, where you can see that the nights are longer than the day.
In the southern hemisphere, the winter season begins from the June solstice, reaching its culmination with the arrival of the equinox in September. Its duration is ninety-four days.
Its characteristic climatology can be appreciated between the months of December to February for the north of the earth and for the southern part of the planet, it covers the months of June to August.
Solstices and Equinoxes
According to the combination of the rotational movements of the earth on its own axis and also by the angle it describes with respect to its orbit, the seasons of the year are produced.
According to the path that the earth makes through the orbit, the incidence of the sun's rays changes. This translates into a transformation of the heat energy of the earth's surface.
The changes or variations in the incidence of sunlight on the earth, produce four points in the trajectory of the earth, which are: two solstices and the same number of equinoxes.
Each one of them will be treated separately, so that you have a better idea of what they are about and their influence on the seasons of the year.
Summer Solstice or June
It can be said that the summer solstice is the event that marks the longest day of the year, in addition to the beginning of summer itself. This event occurs throughout the summer, in each hemisphere, for this reason, it occurs twice a year.
At this time, the sun is on its path, oriented more towards the extreme north in the northern hemisphere. It coincides in the month of June, between the 21st or 22nd of that same month.
As a result of the tilt of the earth's axis in a north-south direction, both summer and winter solstices occur. Said inclination in the axis causes the incidence of solar rays to reach different areas of the planet and in various intensities.
It is known that in the northern hemisphere, during the June solstice, the day is much longer than the night. This is due to the fact that the sun travels the longest route during this period, when it reaches its highest position in the sky.
That is, the direction of the north pole is located with a greater inclination, with respect to the sun. While at the opposite pole, the complete opposite occurs, this phenomenon is known as the winter solstice.
The Tropics of Cancer and Capricorn
In each hemisphere, both north and south, there are two parallel lines, each of these lines is known as the tropics. In the northern hemisphere is the Tropic of Cancer and in the southern hemisphere is the Tropic of Capricorn. in these Earth Dimensions, is where the sun is directly above it, at midday once a year.
Location and Characteristics
It is the parallel of Capricorn, who specifies the southernmost point and where the sun has its most vertical position of the year, at noon and is known as the winter or summer solstice.
This imaginary line that represents the Tropic of Capricorn, crosses several points in the geography of three continents, namely: America, Africa and Oceania, which include countries such as:
- Argentina
- Paraguay
- Brazil
- Chile
- South Africa
- Madagascar
- Namibia
- Mozambique
- Botswana
- Australia
- French Polynesia
In addition to crossing three great Seas and oceans, such as: the Indian, the Atlantic and the Pacific.
The Tropic of Cancer is located north of Ecuador, for this reason it is in this area of the planet, where the sun's rays directly affect.
It comprises a vast area that groups sixteen countries, in which temperatures are around 18° on average, the winter is quite cold and humid. While summer is distinguished by high temperatures, in contrast to heavy rains resulting from the exchange of wind with the mountain climate. This is the reason why the largest reservoirs of tropical forests are found in this tropic.
weather at the summer solstice
There is a false belief that because more solar energy is received, the days will be extremely hot, but in reality this is not true. In general, there are thirty days of delay, between the moment of greatest solar incidence, with respect to the maximum summer temperature.
Put another way, even though the earth absorbs a lot of solar energy, during the solstice, it takes several weeks for that energy to be expelled as heat.
So, the months of July and August will be where the hottest days of summer occur.
september equinox
During the September equinox, the king star at twelve noon begins its positioning, at the lowest point, while the nights also tend to seem longer and longer.
This phenomenon is an indication that summer is about to end in the northern hemisphere of the earth and autumn will soon begin, almost ending the month of September.
The term equinox is derived from Latin and has a similar meaning to same night. Referring to the phenomenon that only occurs twice a year, in which both day and night last approximately the same number of hours, that is, twelve each.
What happens on an equinox?
As mentioned above, the equinox phenomenon occurs twice during the year, which are characterized by the fact that both day and night have the same period of time.
The equinoxes occur on all the planets that make up the solar system, the event occurs when the sun is located perpendicularly on the equator of any planet.
The fact that the days have a division of twenty-four hours is due to the same causes that generate that the earth has the four seasons well defined.
It can easily be seen that the vernal equinox marks the beginning of spring, almost at the end of March, between the 21st and 22nd of that month, and the autumnal equinox gives way to autumn on September 22nd.
The closer the month of December is, the northern hemisphere will begin to tilt away from the sun, causing the sun's rays to be more accentuated, making the days darker and temperatures drop drastically, characteristics of winter.
Finally, the sun reaches its lowest location point in the sky, at noon, giving way to the solstice in December.
equinox celebrations
Throughout the history of humanity, different civilizations around the planet, took certain natural phenomena for the celebration of worship of their gods.
Such is the case of the celebrations of the Mayan civilization, which gathered around the stepped pyramid in Chichen Itza. There, during the sunset of the sun at the time of the equinox, the rays of the star king filtered through the steps, resembling the shape of a great serpent.
If it is known that the equinoxes are the product of the incidence of the sun's rays, the question does not arise that the equinoxes are only on Earth? and the answer is negative. It has already been mentioned, of the presence of equinoxes and seasons on other planets of the solar system.
In the case of the planet Mars, the tilt on its axis is very similar to that of the earth. Due to such a condition, the seasons are very similar to those on earth. Only because of the planet's distance from the sun, the winter season can last more than one hundred and fifty days.
December or winter solstice
The December solstice or winter solstice, as it is also known, is the period of the year when the sun is at the lowest altitude of its route. Therefore, it is the day that has the longest night of the whole year.
The solstice phenomenon gives way to the winter season. It occurs no more than December 23 for the northern hemisphere and as a maximum date on June 23, in the southern hemisphere.
It is important to keep in mind that while an astrological phenomenon originates in one hemisphere, its counterpart will be taking place in the other, that is, while the winter equinox occurs in one hemisphere, the summer solstice occurs in the other.
According to the position of the earth's axis of rotation, the sun's rays fall on the south pole, leaving the polar areas without exposure to sunlight.
Now, pay attention to this particularity. In the southern zones or those of the southern hemisphere, there will be sunlight at midnight. While, in the polar boreal zone or the northern hemisphere, they will have darkness.
In the warm areas of the southern hemisphere, the phenomenon of the day with the greatest presence of sunlight and the shortest night of the year will occur, beginning the southern summer.
On the contrary, in the northern hemisphere, the shortest day and the longest night of all twelve months occur. Sunlight falls perpendicularly on the Tropic of Capricorn, giving rise to boreal winter.
The winter solstice is related, with meanings of renewal and spiritual rebirth, during this day rituals are celebrated throughout the planet, to commemorate its arrival and celebrate the arrival of another of the seasons of the year.
march equinox
The spring equinox in the northern hemisphere occurs between March 20 and 21 each year. Where in both hemispheres the incidence of solar rays is the same, for this reason the day and night have the same length of time. This astronomical phenomenon is propitiated by the way in which the sun falls on Ecuador.
In the northern hemisphere it is called the spring equinox, while in the southern hemisphere it is known as the autumn equinox and occurs in the month of March of each year, beginning a new stage in the seasons of the year.
This phenomenon is produced by the position in the axis of rotation according to the structure of the earth, which allows the rays of the king star to strike again perpendicularly.
The phenomenon is so magnificent that the north and south poles can be illuminated, despite the fact that the sun is positioned on their horizon. In the southern zones, the day happens to have the same period of time as the night.
When this phenomenon occurs, the foundations are also laid for the beginning of spring in the northern hemisphere, resulting in longer days as June approaches, when the nights become darker. short.
Otherwise, in the southern hemisphere, the March equinox gives rise to the autumn season once summer ends. The days are much shorter and the nights extremely long, until the end of June.
Although the year has 365 days, the time it takes for the earth to complete its orbit is a little more than the year. It requires an extra 360 minutes to complete the cycle and return to the starting point.
This mismatch phenomenon is rearranged every four years, when a longer period of time occurs, which is called a leap year.
Seasons of the year in Mexico
The seasons of the year in Mexico They can be easily seen in different areas of the national territory, where some climatological peculiarities stand out, such as temperature, rain, wind, humidity and the duration of each of the seasons of the year.
In different regions of Mexico, four well-defined seasons are easily distinguished: spring, summer, autumn and winter.
Below are the seasons in Mexico and the period that includes each of them:
- Spring Season: starts on March 21 and ends on June 20.
- Summer: It starts on June 21 and ends on September 23.
- Fall Season: starts on September 21 and ends on December 20.
- Winter: It is given from December 21, ending on March 20.
Although the country is located in the northern hemisphere, there are certain differences with its northern neighbors, due to its proximity to the sea, in addition to its relief that gives it certain characteristics of climatic invariability during the year, in some states.
Spring
The spring season begins in Mexico, from March 21 and ends on June 20.
As in other regions of the planet, as in Mexico, spring is the path that leads from the cold to the heat of summer. Its temperature can easily hover between 30° and 40°C, when it is time for summer to come.
For the area of the Federal District of the country, temperatures close to 17°C can be observed, due to the altitude of the city. It is located at about 2300 meters above sea level.
Summer
The start period of the summer season is from June 21, reaching its end no later than September 23.
It is a season that is characterized by presenting high temperatures during almost the whole day, being able to reach up to 40°C. This period is also characterized by the presence of scattered rains in some areas of the country, either during the day and sometimes at dusk.
High concentrations of humidity are what dominate in this season, but the weather will depend on the region where they are. Thus, for example, the residents of Baja California and Sonora have to live with temperatures that exceed 39°C.
Fall
It is a period that corresponds to start between the 21st and 23rd of September and ends on the 20th of December.
The autumn season is the shortest in Mexico, where an eminently dry climate stands out, although rainy events usually occur at the beginning of the season, caused by the cyclone seasons.
During the fall, fresh and pleasant climates can be appreciated and enjoyed. During the night temperatures drop, while the hours of both day and night are the same.
On the other hand, many Mexican citizens consider that of all the seasons of the year, this one in particular is one of the most satisfying due to its freshness.
Winter
In Mexico, the winter season begins on December 21, ending on March 20. It differs from the rest of the seasons because the temperatures drop dramatically, being able to reach 0°C, in some cities of the country.
Rains are not often observed during this season. In regions very close to the sea, temperatures can be warm thanks to the heat of the sea breeze and water vapor.
