From the school bench, everyone knows that our planet rotates both around the Sun and around its own axis - an imaginary line connecting the two poles - the north and south. This arrangement of things affects the change of pores of the year and time of day.
If you ask the question why it is cold in winter, the most common answer will be: The Sun has moved away from the Earth as far as possible. There is some truth in such a statement, but only partially, because other factors influence the change of seasons.
Reasons for winter cooling
Distance
In the process of rotation, our planet really either approaches the star, then moves away. The maximum distance at which two celestial objects are located (in aphelion, in scientific terms) is 152.1 million km, and the minimum (according to science, it will be “overpowered”) is 147.1. The formation of this opinion was influenced by the fact that the Earth has a spherical shape and moves in orbit in the form of an oval. When the surfaces of the planet and stars are removed, the sun's rays cease to convey their heat and therefore the temperature drops. The northern hemisphere is in this position from December to February.
Short day
But the arrival of cold time is affected not only by the distance between the Sun and the Earth. The axis of our planet is inclined with respect to the orbit, the angle of which is 23.5 degrees. The North Pole is always directed at a star called Polyarnaya, which determines the 6-month inclination of the Earth to the Sun and the same period of time - the deviation of the planet from the star. Thus, the angle of inclination removes the surface, making the day shorter.The sun's rays simply do not have enough time to warm the Earth.
Change in the atmosphere
In addition, the Sun rises less high in the sky. In the aggregate of two facts, a decrease in temperature occurs, which leads to a decrease in evaporation. The concentration of water vapor is the main criterion for the retention of heat near the surface, its decrease and entails the departure of heated air into space. Lowering the temperature causes a better dissolution in the atmosphere of carbonic acid, capable of absorbing infrared radiation. When its proportion decreases, thermal radiation occurs faster.
Winter and summer in different parts of the planet
In the northern hemisphere - winter, in the southern - summer. And vice versa. This is because for one half of the year the northern hemisphere of the Earth tilts toward the Sun, the second tilts. Therefore, some celebrate the New Year-Christmas holidays when it is cold, while others - in the hot season.
But there is still such a thing as geographical zones. And the climate is different depending on the distance separating it from the equator - a conditional line dividing the planet into the northern and southern hemisphere. The equator is perpendicular to the axis of rotation of the Earth, so the angle of inclination is not decisive. The temperature in the regions passing along this conditional line is approximately the same throughout the year and equals 24-28 degrees with the “+” sign. More heat, light and solar radiation fall on this part of the land, because the rays fall at right angles.
A decrease in temperature occurs when moving away from the equator: the farther, the colder.In winter, the flow of solar energy reaches the surface of the earth tangentially, casually. In power, it is inferior to quantity in the summer. Including due to the short daylight hours, the time of which is not enough to warm the air and the earth.
Altitude and temperature
The temperature regime is also affected by the location relative to the level of the oceans. Even in the hottest time in the mountains on the peaks you can see snow caps. The cold air at altitude is due to the fact that the density decreases, and the earth is reluctant to share heat. As a result, the temperature in the mountainous regions is low even in summer, and in winter it is much lower than zero than on the plain.
Thus, the answer to the question: why is it cold in winter, lies in the combination of several factors: the Sun and the Earth are at this time at the most remote distance, and the climate zone is located closer to the north pole than to the equator. In winter, the flow of solar energy weakens, the rays hit the earth at an acute angle, and the sun itself lingers on the horizon for insufficient time to warm the soil. No heat source - no high temperatures.
