We explain what the atmosphere is, where it is located and how it is composed. Also, what are its characteristics and contamination.
What is the Atmosphere?
The atmosphere is the different layers of gases that cover the celestial stars attracted by its gravity until it stabilizes around it, reaching different heights. Its chemical composition can be very varied and, in the case of our planet Earth, it contains the air we breathe and the gases that allow life to exist.
The Earth’s atmosphere is known as the Earth’s atmosphere and this article will focus on it. The Earth’s atmosphere is unique in its composition in the Solar System since it contains the appropriate combination of gases important for life to take place on the planet’s surface.
In the atmosphere the temperature and pressure conditions that allow the hydrological cycle are giventhere is the ozone layer that shields the planet from solar radiation, and friction occurs that reduces meteorites that come from space to dust.
Location of the atmosphere
Earth’s atmosphere is found around the surface of the planetextending from the ground to about 10,000 kilometers around the planet, in various layers of more or less uniform gases.
75% of its gas mass is located in the first 11 km of elevation from the sea surface, and as it gains height it also gains an important measure of pressure.
Composition of the atmosphere
The composition of the atmosphere has varied throughout the history of the planet, especially since the appearance of living beings, which consume certain gases and produce others. However, its composition is mostly nitrogen (78%) and oxygen (21%)along with other important gases such as ozone, hydrogen, carbon dioxide, argon and other noble gases. It also contains a significant presence of water vapor (H2EITHER).
Regions of the atmosphere
Two regions are commonly distinguished in the Earth’s atmosphere, which are:
- Homosphere. Its name comes from its constant and regular composition, which occupies the first 100 km of the atmosphere from the ground. All the gases necessary for life are found there in different proportions.
- Heterosphere. Its name comes from the fact that it is stratified into different layers of gases, which vary according to height and pressure:
- 80-400 kilometers high: molecular nitrogen (N2).
- 400-1100 kilometers altitude: atomic oxygen (O).
- 1100-3500 kilometers altitude: helium (He).
- 3500-10,000 kilometers altitude: hydrogen (H).
Layers of the atmosphere
The Earth’s atmosphere is usually divided into layers, which respond to its variation in temperature and pressure, thus forming a scale called atmospheric thermal gradient. These layers would be:
- Troposphere. The lower layer, which goes from the first 6 to 20 kilometers in height. It is the layer where climatic phenomena occur and the end of the layer is at a temperature of -50 °C.
- Stratosphere. It ranges from 20 to 50 kilometers high, arranged in various strata or phases of air (hence its name). In it, oxygen is transformed into ozone by ultraviolet rays, a process that generates heat, which is why temperatures increase in this layer (-3 °C).
- Ozonosphere. In reality, it is a phase of the stratosphere, where the greatest amount of ozone is produced and, consequently, the well-known ozone layer is found that protects the planet from the direct impact of the sun’s rays, absorbing more than 95%. of them.
- Mesosphere. It extends between 50 and 80 kilometers in height, and contains only 0.1% of the atmospheric air mass. It is the coldest zone in the entire atmosphere: it reaches temperatures of up to -80 °C.
- Ionosphere. Also called the thermosphere, it ranges from 90 to 800 kilometers high, and in it the temperature increases with altitude, according to the presence of the sun’s rays. Temperatures of 1500 °C and even higher have been recorded there.
- Exosphere. The outer layer of the atmosphere, which begins at 800 kilometers and ends at 10,000. There the atoms escape into space, and it is the transit zone between our planet and outer space.
Greenhouse effect
The greenhouse effect is known as the presence of atmospheric gases such as carbon dioxide that form a dense layer in the atmosphere and prevent the escape of Earth’s heat (similar to the walls of a greenhouse). This effect It is vital for the preservation of the earth’s heatessential for life.
Importance of the atmosphere
The atmosphere fulfills vital functions for the stability of the planet, as we have said. Not only allows the perpetuation of biochemical cycles by supplying essential gasesbut also prevents heat leakage into outer space, shields us against meteorites (friction with air disintegrates them) and solar radiation. Without it we would be exposed to the elements of space and dramatic variations in temperature between day and night.
Magnetosphere
The magnetosphere is the name given to the region of the atmosphere in which the planet’s magnetic field is noticeable. This is generated by its rotation movement and by its cast iron heart, which acts like a dynamo. This field is also vital to prevent the solar wind and other forms of electromagnetic radiation from entering our planet. When this occurs, the so-called “auroras” occur.
Space travel
Overcoming the resistance of the atmosphere is one of the main challenges of space travel, as well as overcoming gravity in a sustained manner. The friction that a space shuttle suffers during takeoff in the initial layers of the atmosphere can generate heating, deviation of the trajectory and even breakage of materials. On the other hand, once in the outer layers, the low density of gaseous material will allow movement in a much more gentle manner.
Origin of the atmosphere
The origin of the atmosphere is usually attributed to the presence of gases originating from the early stages of the Solar Systemwhich became trapped in the planet’s gravity, as well as the outgassing of the Earth’s crust as it cooled. To this must be added the ice and water from the impact of comets on Earth and then the appearance of the gases typical of organic life.
Atmosphere pollution
Air pollution occurs mainly in the form of gaseswhich not only enhance the greenhouse effect but also corrode the ozone layer, allowing solar radiation to enter and increasing the temperature of the planet. To this must be added the suspension of toxic particles in the lower layers of the atmosphere, which can lead to acid rain.
