The atmosphere is what makes life possible on Earth. We get the very first information and facts about the atmosphere in elementary school. In high school, we are already more familiar with this concept in geography lessons.
The concept of the earth's atmosphere
Atmosphere is available not only for the Earth, but also for other celestial bodies. This is the name of the gaseous shell surrounding the planets. The composition of this gas layer of different planets is significantly different. Let's look at the basic information and facts about the Earth's atmosphere, otherwise known as air.
The most important part of it is oxygen. Some people mistakenly think that the earth's atmosphere is made entirely of oxygen, but air is actually a mixture of gases. It contains 78% nitrogen and 21% oxygen. The remaining one percent includes ozone, argon, carbon dioxide, water vapor. Let the percentage of these gases be small, but they perform an important function - they absorb a significant part of the solar radiant energy, thereby preventing the luminary from turning all life on our planet into ashes. The properties of the atmosphere change depending onfrom height. For example, at an altitude of 65 km, nitrogen is 86%, and oxygen is 19%.
Composition of the Earth's atmosphere
- Carbon dioxide is essential for plant nutrition. In the atmosphere, it appears as a result of the process of respiration of living organisms, rotting, burning. Its absence from the composition of the atmosphere would make it impossible for any plants to exist.
- Oxygen is a vital component of the atmosphere for humans. Its presence is a condition for the existence of all living organisms. It makes up about 20% of the total volume of atmospheric gases.
- Ozone is a natural absorber of solar ultraviolet radiation, which adversely affects living organisms. Most of it forms a separate layer of the atmosphere - the ozone screen. Recently, human activity has led to the gradual destruction of the ozone layer, but since it is of great importance, active work is underway to preserve and restore it.
- Water vapor determines the humidity of the air. Its content may vary depending on various factors: air temperature, geographical location, season. At low temperatures, there is very little water vapor in the air, maybe less than one percent, and at high temperatures, its amount reaches 4%.
- In addition to all of the above, in the composition of the earth's atmosphere there is always a certain percentage of solid and liquid impurities. These are soot, ash, sea s alt, dust, water drops, microorganisms. They can get into the air both naturally and anthropogenic.
Layers of the atmosphere
The temperature, density, and quality composition of the air is not the same at different heights. Because of this, it is customary to distinguish different layers of the atmosphere. Each of them has its own characteristic. Let's find out which layers of the atmosphere distinguish:
- Troposphere - this layer of the atmosphere is closest to the Earth's surface. Its height is 8–10 km above the poles and 16–18 km in the tropics. Here is 90% of all water vapor that is available in the atmosphere, so there is an active formation of clouds. Also in this layer there are such processes as the movement of air (wind), turbulence, convection. Temperatures range from +45 degrees at noon in the warm season in the tropics to -65 degrees at the poles.
- The stratosphere is the second layer of the atmosphere farthest from the earth's surface. It is located at an altitude of 11 to 50 km. In the lower layer of the stratosphere, the temperature is approximately -55, towards the distance from the Earth it rises to +1˚С. This region is called the inversion and is the boundary between the stratosphere and the mesosphere.
- The mesosphere is located at an altitude of 50 to 90 km. The temperature at its lower boundary is about 0, at the upper it reaches -80 … -90 ˚С. Meteorites that enter the Earth's atmosphere burn up completely in the mesosphere, which causes airglows here.
- The thermosphere is approximately 700 km thick. The northern lights appear in this layer of the atmosphere. They appear due to the ionization of air under the influence of cosmic radiation and radiation emanating from the Sun.
- The exosphere is a zone of air dispersion. Herethe concentration of gases is small and their gradual escape into interplanetary space occurs.
The boundary between the earth's atmosphere and outer space is considered to be a line of 100 km. This line is called the Karman line.
Atmospheric pressure
When listening to the weather forecast, we often hear barometric pressure readings. But what does atmospheric pressure mean, and how might it affect us?
We figured out that the air consists of gases and impurities. Each of these components has its own weight, which means that the atmosphere is not weightless, as was believed until the 17th century. Atmospheric pressure is the force with which all layers of the atmosphere press on the surface of the Earth and on all objects.
Scientists carried out complex calculations and proved that the atmosphere presses on one square meter with a force of 10,333 kg. This means that the human body is subject to air pressure, the weight of which is 12–15 tons. Why don't we feel it? It saves us its internal pressure, which balances the external one. You can feel the pressure of the atmosphere while in an airplane or high in the mountains, since the atmospheric pressure at altitude is much less. This may cause physical discomfort, stuffy ears, dizziness.
Interesting information and facts
A lot can be said about the atmosphere surrounding the globe. We know a lot of interesting facts about her, and some of them may seem surprising:
- Earth's atmosphere weighs 5,300,000,000,000,000 tons.
- It contributes to the transmission of sound. Above 100 km, this property disappears due to changes in the composition of the atmosphere.
- The movement of the atmosphere is provoked by uneven heating of the Earth's surface.
- A thermometer is used to determine air temperature, and a barometer is used to determine the pressure of the atmosphere.
- The presence of an atmosphere saves our planet from 100 tons of meteorites daily.
- The composition of the air was fixed for several hundred million years, but began to change with the onset of rapid industrial activity.
- The atmosphere is believed to extend upwards to an altitude of 3000 km.
The importance of the atmosphere for humans
The physiological zone of the atmosphere is 5 km. At an altitude of 5000 m above sea level, a person begins to experience oxygen starvation, which is expressed in a decrease in his working capacity and a deterioration in well-being. This shows that a person cannot survive in a space where this amazing mixture of gases does not exist.
All information and facts about the atmosphere only confirm its importance for people. Thanks to its presence, the possibility of the development of life on Earth appeared. Already today, having assessed the scale of harm that humanity is capable of inflicting with its actions on the life-giving air, we should think about further measures to preserve and restore the atmosphere.
