What is the troposphere? Lower layer of the atmosphere and its meaning

The gas shield of our planet, which protectsit from the rigid cosmic influences from the outside, is called the atmosphere. Without it, life on Earth would be impossible. Its thickness is several thousand kilometers, and consists of an atmosphere of several layers. Which of them is called the troposphere?

Definition

What is the troposphere and what is its thickness? All the changes that occur in this layer of the atmosphere have a significant impact on the weather conditions on Earth. The lowest layer of the atmosphere is called the troposphere. It is about 75% of its total mass. The troposphere contains 99% of the total mass of aerosols of the atmosphere and water vapor.

This word came from the ancient Greek language. It consists of two roots - "tropos" (turn, change) and "sphere" (ball). The troposphere is the lower layer of the gas shell, which most closely interacts with the upper layers of our planet - the hydrosphere and the lithosphere. In it there is a constant exchange of moisture, heat, and also chemical elements.

Properties

Interested in what the troposphere is,It is interesting to know that its thickness is not the same. In temperate latitudes it does not exceed 17 km, in the tropics - 20 km. Near the poles of the globe it is no more than 10 km. The lower layer of the troposphere is borderline, and its depth ranges from several hundred meters to 2 km.

It is heavily influenced by airstreams on the surface of the planet, the outline of the land, as well as the circadian rhythm. After every 100 m of the rise in the tropospheric layer of the gas shell, the air temperature in the troposphere drops by an average of 0.65 degrees Celsius. The total thickness of the atmosphere does not exceed 25 thousand km.

As the air density decreases,The atmosphere without any clear boundary passes into outer space. At the same time, the upper boundary of the gas shell ends at 20,000 km. The lower boundary of the troposphere passes along the surface of the planet.

Composition of the troposphere

The surface layer consists of two majorchemical elements - nitrogen and oxygen. The nitrogen content is 78% of the total gas envelope of the Earth; of oxygen - 21%. The most important role for the maintenance of life on our planet is played by water, oxygen and carbon dioxide. An important role in the process of plant nutrition is played by the nitrogen cycle. Also an important component is water vapor, thanks to which the necessary temperature level is maintained. Steam enters the troposphere due to evaporation from the surface of the ocean.

Nitrogen, a large part of which is contained inatmosphere, serves as a kind of diluent for oxygen. About carbon dioxide, we can say that its content in the gas shell of the planet is quite variable. Carbon dioxide enters the troposphere from various sources - volcanic eruptions, from organisms, from soil, products of biological decay, etc. Despite its low content in the troposphere, its role for life maintenance is exceptionally high, because it is necessary for plants for photosynthetic processes .

Also of great importance for the troposphere is anddust, most of which rises from the continents. It includes particles of various minerals, salts, spores and microorganisms. The cloudiness of the atmosphere due to dust weakens the planet's protection from solar radiation.

Processes in the troposphere

The layer following the troposphere is the stratosphere. The atmosphere also includes other layers - the mesosphere, the exosphere and the thermosphere. However, the most important layer for maintaining life on Earth is the troposphere, more precisely, its lower layer. The two layers are separated by a tropopause - a thin transition region where the temperature ceases to decrease in proportion to the height increase.

The biosphere, as well as most of the atmosphericair are located in the troposphere. It is here that different types of clouds are formed, weather fronts and air masses, cyclones and anticyclones are formed. In the troposphere is the whole system of air currents. As a result of condensation processes, clouds form causing precipitation of precipitation in the form of rain, hail, or snow.

Transitions of water from one state to anotherare carried out precisely in the troposphere. At the surface of the planet, air pressure is higher than in the upper layers. The processes occurring in this layer of the atmosphere affect the climate and weather conditions.

The significance of the atmosphere

What is the role of the gas envelope of our planet? First, in its lower layer - namely, in the troposphere - practically all the air reserves are concentrated. Thanks to these stocks, living organisms are able to breathe. The significance of the atmosphere for life on Earth can not be overemphasized - because without air our planet would be uninhabited, like other celestial bodies in the solar system. And in the upper part of the gas shell is the ozone layer, which protects the Earth from cosmic influences. Thanks to him, dangerous cosmic radiation does not reach our planet.

Surface layer

Those who study what the troposphere is, shouldTo know also about its lowest layer, which is called the surface layer. It contains a large amount of dust, as well as various volatile microorganisms. In the ground layer, the daily temperature variations, as well as the humidity of the air, are well pronounced. With increasing altitude, the wind speed increases. In this layer there is a vertical distribution of air temperature.

What is the troposphere and what is its significance forall living things on Earth, every schoolboy knows. After all, it is its surface layer that represents the habitat for all living organisms. Gases from the lithospheric faults, as well as the existence of life, have a great influence on the composition and structure of the surface layer of the troposphere.