What is the main feature of the structure of the Earth. Internal structure of layers of land - bark, mantle, core

Earth's subsoil are very mysterious and almost inaccessible. Unfortunately, there is still no such device with which you can penetrate and explore the internal structure of the Earth. The researchers have established that at the moment the deepest mine in the world has a depth of 4 km, and the deepest well is located on the Kola Peninsula and is 12 km.

However, certain knowledge of the depths of our planet is still installed. Scientists have studied its internal structure using the seismic method. The basis of this method is the measurement of oscillations during an earthquake or artificial explosions produced in the depths of the Earth. Substances with different density and composition, passed fluctuations at a certain speed. What allowed using special devices to measure this speed and analyze the results obtained.

Opinion scientists

The researchers have found that our planet has several shells: earthly bark, mantle and core. Scientists believe that approximately 4.6 billion years ago began the bundle of the Earth's subsoil and continues to settle, to this day. In their opinion, all heavy substances descend to the center of the Earth, joining the core of the planet, and lighter substances rise up and become earthly crust. When the inner bundle is over, our planet turn into a cold and dead.

Earth's crust

It is the finest shell of the planet. Its share is 1% of the total mass of the Earth. People live on the surface of the earth's crust and get everything they need to survive from it. In the earth's crust, in many places, there are mines and wells. Its composition and structure is studied using samples collected from the surface.

Mantle

It is the most extensive shell of the Earth. Its volume, and the mass is 70 - 80% of the entire planet. The mantle consists of a solid, but less dense than the substance of the kernel. The deeper the mantle is located, the more its temperature and pressure becomes. Mantle has a partially molten layer. With this layer, solids move to the Earth's kernel.

Core

It is the center of the Earth. It has a very high temperature (3000 - 4000 o C) and pressure. It consists of a kernel of the tight and heavy substances. It is approximately 30% of the total mass. The solid part of the nucleus floats in its liquid layer, thereby creating the magnetic field of the Earth. It is a defender of life on the planet, protecting it from cosmic rays.

Scientific and popular film about the formation of our world

Internally, the structure of the Earth is one of the most interesting and poorly studied those modern scientists. Today, we have ten times more information about space than what is happening in the heart of our planet. The person is inside the earth's crust so scrubly as the mosquito sting can stay human skin. The thing is that the top layer of the whole globe is rather dense in its composition the earthly bark. And to drill a well in it, having the most modern equipment, you need to spend several months, and it will be all a few kilometers away.

And what is a few kilometers in comparison with several thousand? The main role in the study of the internal layers of the Earth is given by seismology. Ideally, this is a science that studies earthquakes. But it is precisely thanks to seismic methods (natural earthquakes or artificial explosions) managed to find out that the entire inside of the planet is conditionally divided into three parts - the earth's bark, viscous mantle and core.

Earth's crust

The earth Cora is a solid Earth shell and is the top of the lithosphere. Its most of it is under the world ocean and from here there is a division of the bark on the oceanic (occupies 21%) and continental (79%). If we take a total mass of the planet for 100%, then the bark has only 0.47%. For the earth's crust, constant horizontal and vertical movements are characterized, which leads to the formation of various form of relief. The division of the cortex on the mainland and oceanic substantially is distinguished in the structure.

The mainland is much thicker than the oceanic, and its border does not coincide with coastline World Ocean. From the geographical point of view, it is believed that coastal zones, small sea, bays with a depth of 200 meters are a continuation of the continental part. After all, as studies show, finding small water bodies on a particular territory - the phenomenon is not permanent. The ocean part of the bark begins where the depth of water reaches 4 kilometers.

The mainland bark form three layers:

• Sediment - its thickness in some places reaches up to 15 km. And the layer was obtained due to the fact that it consists of sediments of various types, which for millions of years accumulated a layer behind the layer. The study of this layer allows scientists to observe various geological processes, trace the stages of raising and lowering the bark.
• The granite layer got its name as a result of the same speed of seismic waves in it and in the granite. It consists of rocks of crystalline origin, which were formed as a result of raising magma from the depths of the Earth.
• The basalt layer got its name as much due to the speed of seismic waves in it. The lower limit of this layer can reach 70 km in the depth and, accordingly, no one knows the exact composition. According to one assumption, it consists of basalt, in others - from metamorphic breeds with high degree Metamorphism.

The ocean part of the earth's crust differs in the composition of the mainland, although in its structure it also has three layers. The sedimentary layer in the ocean part in the width reaches only 1 km. The granite layer is absent, and in its place there is a little studied part, which is most often referred to as the second or an intermediate layer. Well, the third is a basalt layer, which in its structure is similar to the mainland. It should be noted that the thickness of the earth's crust of the ocean type is only 3-7 km, which is much smaller than the mainland.

Mantle

Part of the land, which is located under the earth's crust, is called mantle. This is the most bulky part, it is 67% on its mass. The upper boundary of the mantle is at a depth of 30 km, and the lower - 2900 km from the surface. The gap between the bark and mantia is called Mochorovich's zone. In turn, the mantle itself is divided into several areas: the upper (depth of up to 900 km) and the lower mantle. The processes that occur in the mantle are significantly affected by the surface of the Earth and on the Crara itself. It is due to the viscous composition of the mantle, the movement of lithospheric plates occurs, the eruption of volcanoes, earthquakes and the formation of various ore deposits.

According to one of the opinions of scientists, it is believed that the mantle consists of elements that were in solid state during the formation of the planet. Iron and magnesium were combined with silicon dioxide and formed silicates. Magnesium silicates are in the upper part of the mantle, and the amount of iron silicates increases with the depth. At the bottom of the mantle they decompose on oxides. With increasing depth, there is a significant increase in temperature and pressure. Study of mantle for a long time It is of great interest among the scientists of the entire planet. The study of rocks, which, according to scientists, is part of the upper and lower mantle, led them to the conclusion that in its lower part there is significantly the amount of silicon. And for the upper layer, water reserves are characterized, which are seeping there through the earth's bark, as well as capable of climbing back.

The core of the globe

In the very center of our planet, the core is located, which occupies 31.5% of the entire mass of the Earth. As well as the remaining internal components of the planet, the core consists of several parts - the external and inner core. According to the studies, it was found that the iron and nickel alloy prevails as part of the kernel. The outer part of the core has a radius of about 2,200 km, and in composition it is more liquid. The inner part is smaller in size, its radius is 1300 km and it is more dense. Our planet has a magnetic field, the creation of which the internal structures of the Earth have a direct impact.

This suggests that the kernel should be a wiring. Average density The substance that is included in the kernel is 11 t / m3. Such a density can only be at the metal. The exact composition of the kernel cannot find out by any scientist, as it is simply unreal with samples from the center of the Earth. And all the information that is available is only guesses and assumptions.

Analyzing all of the above, it can be concluded that the internal structure of the Earth is very complex. On the one hand, everything is simple - bark, mantle, core. But on the other hand, we cannot look at the inside, so that there are 100% confident in what is happening there. It is proved that the planet was formed from the cluster of various pieces of meteorites, asteroids, comets, dust and dirt. All these particles form a land without a certain order. And he says that it was originally in all areas there were pieces of the same composition. In order to formed geographic shellsSo that the inner layers of the globe occurred, gigantic processes should occur.

I analyze the dynamics of the development of the earth's crust, we are once again convinced that these processes are not fading now. Billions of years there is a movement of lithospheric plates, the formation of huge depressions, the influence of the lava, the formation of the mountains. Then it all collapses and re-erected. All this is possible only if there is huge energy and substances that do not cease to stand out from the bowels of the earth. To find out the causes of all these processes and solve their relationship between themselves - this is the main task of scientists, on which one decade will take another decade.

Such a question as the structure of the Earth is interested in very many scientists, researchers and even believers. With the rapid development of science and technology from the beginning of the 18th century, many decent science workers spent a lot of effort in order to understand our planet. The bolts went down to the bottom of the ocean, flew into the highest layers of the atmosphere, drilled the huge depth of the well to study the soils.

Today there is a fairly one-piece picture of what the land is made. True, the device of the planet and all its regions is still 100%, but scientists gradually expand the verge of knowledge and get more and more objective information about this.

Form and dimensions of the planet Earth

The shape and geometric dimensions of the Earth are the basic concepts that it is described as heavenly body. In the Middle Ages it was believed that the planet had a flat shape, located in the center of the universe, and the sun and other planet rotates around it.

But such bold naturalists like Jordan Bruno, Nikolai Copernicus, Isaac Newton denied similar judgments and mathematically proved that the earth has the shape of a ball with the shiny poles and revolves around the Sun, and not the opposite.

The structure of the planet is very diverse, despite the fact that its size is quite small by the standards of even the solar system - the length of the equatorial radius is 6378 kilometers, the polar radius is 6356 km.

The length of one of the meridians is 40008 km, and the equator extends 40007 km. It is also seen from this that the planet somewhat "falls" between the poles, its weight is 5.9742 × 10 24 kg.

Earth shell

The earth consists of many shells forming peculiar layers. Each layer is centrally symmetrical with respect to the base central point. If you visually cut a section of the soil throughout its depth, the layers will open different composition, aggregate state, density, etc.

All shells are divided into two large groups:

1. The inner structure is described, respectively, inner shells. They are the earth bark and land of the Earth.
2. External shells to which the hydrosphere and the atmosphere belong.

The structure of each shell is the subject of studying individual sciences. Scientists still, in the age of violent technical progress, not all the questions found out to the end.

Earth Cora and its types

The earth Cora is one of the planet shells, which occupies only about 0.473% of its mass. Corn depth 5 - 12 kilometers.

It is interesting to note that the scholars practically did not penetrate the deeper, and if they carry out an analogy, the bark is like a skin on an apple in relation to its volume. Further and more accurate study requires a completely different level of development of technology.

If you look at the planet in a context, then as it is from the depth of penetration inside its structure, it is possible to allocate such types of the earth's crust in order:

1. Oceanic bark - It consists mostly from basalt, located at the bottom of the oceans under huge layers of water.
2. Continental or mainland bark - Sushi covers, consists of a very rich chemical composition, including 25% silicon, by 50% oxygen, as well as 18% of other major elements of the Mendeleev table. In order to conveniently study this bark, it is still divided into the lower and top. The most ancient belong to the bottom.

The temperature of the cortex increases as depicted.

Mantle

The main volume of our planet is mantle. It occupies the entire space between the crust and the core discussed above and consists of many layers. The smallest thickness to the mantle is about 5 - 7 km.

The modern level of development of science and technology does not allow directly to study this part of the Earth, so indirect methods use to obtain information about it.

Very often the birth of a new crust is accompanied by its contact with the mantle, which is particularly actively happening in places under the ocean waters.

Today it is believed that there is an upper and lower mantle, which are divided by the border of Mochorovichi. The percentage of this distribution is calculated definitely, but require refinement in the future.

External kernel

The core of the planet is also not homogeneous. Huge temperatures, the pressure is forced to flow here many chemical processes, the mass distribution is carried out, substances. The kernel is divided into inner and external.

The external core has a thickness of about 3,000 kilometers. Chemical composition This layer: iron and nickel in the liquid phase. The temperature of the medium here ranges from 4400 to 6100 degrees Celsius as the center approaches the center.

Inner kernel

The central part of the Earth, the radius of which is about 1,200 kilometers. The lowest layer, which also consists of iron and nickel, as well as some impurities of light elements. State of aggregation This kernel is similar to amorphous. The pressure here reaches an incredible 3.8 million bar.

Do you know how many kilometers to the nucleus of the Earth? The distance is approximately 6371 km, which is easily calculated if you know the diameter and other parameters of the ball.

Comparison of the power of the inner layers of the earth

The geological structure is sometimes estimated by such a parameter as the power of the inner layers. It is believed that the most powerful is the mantle, since it has the greatest thickness.

External spheres of the globe

Planet Earth differs from any other known scientist space object By the fact that the external spheres belong to:

• hydrosphere;
• atmosphere;
• biosphere.

Methods for studying these areas are significantly different, because they are all very different in their composition and the object of study.

Hydrosphere

Under the hydrosphere, the entire water shell of the Earth is understood, including both huge oceans, occupying about 74% of the surface and the sea, rivers, lakes, and even small streams and reservoirs.

The largest thickness of the hydrosphere is about 11 km and is observed in the area of \u200b\u200bthe Mariana Vpadina. It is the water that is considered a source of life and the fact that our ball is different from all the others in the universe.

The hydrosphere occupies about 1.4 billion km 3 volume. Life boils here, and the conditions for the functioning of the atmosphere are ensured.

Atmosphere

Gas shell of our planet, reliably closing its subsoil from space objects (meteorites), cosmic cold and other phenomena incompatible with life.

The thickness of the atmosphere is about 1000 km from different estimates. Near the surface of the soil density of the atmosphere is a density of 1.225 kg / m 3.

By 78%, the gas shell consists of nitrogen, 21% of oxygen, the rest falls on elements such as argon, carbon dioxide, helium, methane and others.

Biosphere

In independence, scientists, the biosphere is studying the question under question, the biosphere is the most important part of the structure of the Earth - this is the shell, which is inhabited by living beings, including the people themselves.

The biosphere is not just inhabited by living beings, but also constantly changes under their impact, in particular, under the influence of man and its activities. Holistic teaching about this area developed a great scientist V. I. Vernadsky. The most this definition introduced an Austrian geologist Zyuss.

Conclusion

The surface of the Earth, as well as all the shells of its external and internal structure are very an interesting subject Studies for whole generations of scientists.

At least at first glance it seems that the areas considered are quite scattered, but in fact they are bound by indiscriminate connections. For example, life and the entire biosphere is simply impossible without the hydrosphere and atmosphere, the same, in turn, originate from the subsoil.

Quoted1 \u003e\u003e From what is the land

Description earth composition For children with photo: The structure of the planet in the figure, which consists of the bark, mantle and the core, what the upper shell looks like, the thickness of the layers.

Earth - the third planet from the Sun, but also the only planet in Solar system and the famous universe where the developed form of life lives. It is a native home that children will be useful to explore. Let us consider in detail the structure of the Earth, which will help our photos, schemes and pictures.

To begin explanation for children About the composition of the Earth follows from the fact that we live on a unique planet, as there is water on it. Of course, there are other worlds, as well as satellites, where there is an atmosphere, ice and even oceans, but only we were lucky to have all the factors for creating and maintaining life.

For the smallest It is important to know that the earth's oceans occupy approximately 70% of the entire surface, and depth is 4 km away. In liquid form fresh water Located in rivers, lakes and in the form of an atmospheric water vapor, which leads to a large weather variety.

Follow explain the childrenthat the land is multi-layer. External reproaches. It fills in oceanic pools and continents. The earth Cora takes 5-75 km. The most dense parts are hidden under the continents, and thin - under the oceans. Now let's study the composition of the Earth in the layers: bark, mantle, core.

Earth Bark - Explanation for children

The earth's crust contains such elements as: oxygen (47%), silicon (27%), aluminum (8%), iron (5%), calcium (4%), and 2% magnesium, potassium and sodium. It is created in the form of giant plates that are moving in liquid mantle. Important explain the childrenthat, although we do not notice, but the plates do not stop movement. When they face, we feel the earthquake, and if one goes to another, then a deep trench or mountain is formed. These movements describe the theory of plate tectonics.

Earth's Mantle - Explanation for Children

Further, with a thickness of 2890 km, there is a mantle. It is represented by silicate rocks rich in magnesium and iron. Due to intense heat, rocks are created. Then they cooled and return to the kernel again. Believe exactly what it leads tectonic plates in motion. When the mantle can break through the bark, you see the volcanic eruption.

Earth's core - Explanation for children

Surely, even for the smallest It is clear that the kernel is located inside the ground. Interestingly, it consists of two halves: an internal (solid) with a radius of 1220 km is surrounded by external (liquid - nickel and iron alloy) with a thickness of 2180 km. While the planet rotates in the usual pace, the inner kernel makes turns separately, forming a magnetic field. You can also tell children About how polar radiances are formed. After all, for this, the charged particles of the solar wind need to go into the air molecules above the magnetic poles of the planet and then these molecules begin to shine.

Now you know the land. If children or schoolchildren of any age will curious to learn more interesting facts And the details about the third planet from the sun, be sure to visit the rest of the partition page. Do not forget to use the 3D model of the solar system, where all the planets are shown, as well as the Map of Venus, its surface and the features of orbit. Other, you will always help our photos, pictures, drawings, as well as an online telescope that is functioning in real time. The structure of the land is incredibly easy to understand if you follow the visual row.

The land relates to the planets of the Earth Group, and, unlike gas giants, such as Jupiter, has a solid surface. This is the largest of the four planets of the earth group in the solar system, both in size and mass. In addition, the Earth among these four planets has the greatest density, surface gravity and magnetic field. This is the only one famous planet with active tactical slabs.

Earth's subsoil is divided into layers in chemical and physical (rheological) properties, but unlike other planets of the earth group, the Earth has a pronounced external and inner core. Outer layer Earth is a solid shell consisting mainly of silicates. From the mantle, it is separated by the boundary with a sharp increase in the rates of longitudinal seismic waves - the surface of Mochorovichich. The solid bark and the viscous top of the mantle make up a lithosphere. Under the lithosphere is an asthenosphere, a layer of relatively low viscosity, hardness and strength in the upper mantle.

Significant changes in the crystal structure of the mantle occur at a depth of 410-660 km below the surface covering the transition zone, which separates the upper and lower mantle. Under the mantle is a liquid layer consisting of molten iron with nickel, sulfur and silicon impurities - the core of the Earth. Seismic measurements show that it consists of 2 parts: a solid inner core with a radius of ~ 1220 km and a liquid external core, with a radius of ~ 2250 km.

The form

Earth shape (geoid) is close to a flattened ellipsoid. The discrepancy between the geoid with the approximating ellipsoid reaches 100 meters.

Earth rotation creates equatorial convexity, therefore, the equatorial diameter is 43 km more than polar. The highest point of the earth's surface is Mount Everest (8848 m above sea level), and the deepest - Mariana Wpadina (10,994 m at sea level). Due to the bulk of the equator, the removed surface points from the center of the Earth are the top of the Chimborace Volcano in Ecuador and Mount Wastern to Peru.

Chemical composition

Earth weight is approximately equal to 5,9736 · 1024 kg. The total number of atoms constituting the Earth, ≈ 1.3-1.4 · 1050. It consists main of iron (32.1%), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8 %), calcium (1.5%) and aluminum (1.4%); The remaining elements account for 1.2%. Due to segregation by weight, the kernel region, presumably consists of iron (88.8%), a small amount of nickel (5.8%), sulfur (4.5%) and about 1% of other elements. It is noteworthy that carbon, which is the basis of life, in the earth's crust is only 0.1%.

Geochemist Frank Clark calculated that the earth is slightly more than 47% composed of oxygen. The most common breed-forming minerals of the earth's crust are almost completely composed of oxides; The total chlorine, sulfur and fluorine content in rocks is usually less than 1%. The main oxides are silica (SiO 2), alumina (Al 2 O 3), iron oxide (FEO), calcium oxide (CAO), magnesium oxide (MgO), potassium oxide (K 2 O) and sodium oxide (Na 2 O) . Silica serves mainly by the acid medium, forms silicates; The nature of all major volcanic rocks is associated with it.

Internal structure

Earth, like other planets of the earth group, has a layered internal structure. It consists of solid silicate shells (bark, extremely viscous mantle), and metal kernel. The outer part of the kernel is liquid (significantly less viscous than mantle), and internal - solid.

Inner heat

The inner heat of the planet is ensured by a combination of residual heat remaining from the accretion of the substance that occurred at the initial stage of the formation of the Earth (about 20%) and the radioactive decay of unstable isotopes: potassium-40, uranium-238, uranium-235 and thorium-232. In three of the listed isotopes, the half-life is more than a billion years. In the center of the planet, the temperature may rises to 6000 ° C (10,830 ° F) (more than on the surface of the Sun), and the pressure can reach 360 GPa (3.6 million atm). Part of the thermal energy of the nucleus is transmitted to the earth's crust through plumes. Plums lead to the appearance of hot spots and trapps. Since most of the heat produced by the earth is provided by radioactive decay, then at the beginning of the history of the Earth, when the reserves of short-lived isotopes have not yet been exhausted, the energy release of our planet was much more than now.

Most of all the energy is lost with the tactics of the plates, the lifting of the substance of the mantle on the mid-ocean ridges. The last major type of heat loss is heat loss through the lithosphere, and more heat lifting is happening in this way in the ocean, as the earth's edge is much thinner than under continents.

Lithosphere

Atmosphere

Atmosphere (from. Dr. Greek.? Τμ? Σ - pairs and σφα? Ρα - ball) - Gas shell surrounding the planet Earth; It consists of nitrogen and oxygen, with trace amounts of water vapor, carbon dioxide and other gases. Since its inception, it has changed significantly under the influence of the biosphere. The appearance of an oxygen photosynthesis 2.4-2.5 billion years ago contributed to the development of aerobic organisms, as well as the saturation of the atmosphere with oxygen and the formation of the ozone layer, which protects everything alive from harmful ultraviolet rays.

The atmosphere determines the weather on the surface of the Earth, protects the planet from cosmic rays, and partly - from meteorite bombing. It also regulates the main climate-forming processes: water cycle in nature, circulation of air masses, heat transfer. Molecules of atmospheric gases can capture thermal energyI prevent her to go into open space, thereby increasing the temperature of the planet. This phenomenon is known as greenhouse effect. Basic greenhouse gases are considered water vapor, carbon dioxide, methane and ozone. Without this effect of thermal insulation, the average surface temperature of the Earth would be from -18 to -23 ° C (despite the fact that in reality it is 14.8 ° C), and life most likely would not exist.

At the bottom of the atmosphere contains about 80% of the total mass and 99% of the total water vapor (1.3-1.5 × 1013 tons), this layer is called triposfer. Its thickness is non-model and depends on the type of climate and seasonal factors: so, in the polar regions it is about 8-10 km, in moderate belt up to 10-12 km, and in tropical or equatorial reaches 16-18 km. In this layer atmosphere, the temperature is lowered by an average of 6 ° C per kilometer when moving in height. The above is the transition layer - the tropopause separating the troposphere from the stratosphere. Temperature here is within 190-220 K.

Stratosphere- a layer of atmosphere, which is located at a height of 10-12 to 55 km (depending on weather conditions and season). It accounts for no more than 20% of the entire mass of the atmosphere. For this layer, a decrease in temperature is characterized up to a height of ~ 25 km, followed by an increase on the border with a mesosphere almost to 0 ° C. This boundary is called strato-eyed and is located at an altitude of 47-52 km. The stratosphere marks the greatest concentration of ozone in an atmosphere that protects all living organisms on Earth from the harmful ultraviolet radiation of the Sun. Intensive absorption solar radiation The ozone layer causes a rapid rise in temperature in this part of the atmosphere.

Mesosphereit is located at an altitude of 50 to 80 km above the surface of the Earth, between the stratosphere and the thermosphere. It is separated from these layers of mesopaousis (80-90 km). This is the coldest place on Earth, the temperature here is lowered to -100 ° C. With this temperature, the water contained in the air quickly freezes, sometimes forming silver clouds. They can be observed immediately after sunset, but the best visibility is created when it is from 4 to 16 ° below the horizon. Most of the meteorites penetrating into the earth's atmosphere burns in the mesosphere. From the surface of the earth, they are observed as falling stars. At an altitude of 100 km above sea level there is a conditional border between the earth's atmosphere and space - pickline line.

IN thermosphere The temperature quickly rises to 1000 K, this is due to the absorption of short-wave solar radiation in it. This is the longest layer of the atmosphere (80-1000 km). At an altitude of about 800 km, the temperature rise stops, since the air here is very cleaned and weakly absorbs solar radiation.

Ionosphereincludes the last two layers. Here is the ionization of molecules under the action of solar wind and polar radiances occur.

Exosphere - External and very sparse part of the earth's atmosphere. In this layer, the particles are able to overcome the second space speed of the Earth and disappear into outer space. This causes a slow, but a steady process called the atmosphere dissipation (scattering). Space escapes in the main particle of light gases: hydrogen and helium. Hydrogen molecules having the lowest molecular weight, It can be easier to reach the second cosmic speed and to flow into the outer space with a faster pace than other gases. It is believed that the loss of reducing agents, for example hydrogen, was prerequisite For the possibility of sustainable oxygen accumulation in the atmosphere. Consequently, the property of hydrogen leave the atmosphere of the Earth, perhaps affected the development of life on the planet. Currently, most of the hydrogen falling into the atmosphere is converted into water without leaving the earth, and the loss of hydrogen occurs mainly from the destruction of methane in the upper layers of the atmosphere.

Chemical composition of the atmosphere

At the surface of the Earth, the decessed air contains about 78.08% nitrogen (by volume), 20.95% oxygen, 0.93% of argon and about 0.03% carbon dioxide. The volume concentration of the components depends on the humidity of the air - the content of a water vapor in it, which ranges from 0.1 to 1.5%, depending on the climate, the season, the area. For example, at 20 ° C and relative humidity of 60% (the average humidity of the room air in summer) oxygen concentration in the air is 20.64%. The fraction of the remaining components accounts for no more than 0.1%: it is hydrogen, methane, carbon monoxide, sulfur oxides and nitrogen oxides and other inert gases except argon.

Also in the air there are always solid particles (dust are particles of organic materials, ashes, soot, pollen of plants, etc., at low temperatures - ice crystals) and water drops (clouds, fog) - aerosols. The concentration of solid dust particles decreases with a height. Depending on the time of year, climate and terrain, the concentration of aerosol particles in the atmosphere varies. Above 200 km The main component of the atmosphere - nitrogen. At a height of over 600 km, helium prevails, and from 2000 km - hydrogen ("hydrogen crown").

Biosphere

Biosphere (from Dr. Greek. Βιος - life and σφα? Ρα - sphere, ball) - this is a set of parts earth shells (litto, hydro and atmosphere), which is populated by alive organisms, is under their impact and is engaged in products of their livelihoods. The biosphere is a land shell populated by alive organisms and converted by them. It began to form no earlier than 3.8 billion years ago, when the first organisms began to be born on our planet. It includes the entire hydrosphere, the upper part of the lithosphere and the lower part of the atmosphere, that is, inhabit the ecosphere. The biosphere is a totality of all living organisms. It lives in two million species of plants, animals, mushrooms and microorganisms.

The biosphere consists of ecosystems, which include communities of living organisms (biocenosis), their habitat (biotop), communication systems that carry out the metabolism and energy between them. On land, they are separated mainly by geographic latitudes, height above sea level and differences in precipitation. Ground ecosystems located in the Arctic or Antarctic, large altitudes or in extremely arid areas, relatively poor plants and animals; A variety of species reaches a peak in wet rainforest equatorial belts.

Magnetic field of land

The magnetic field of the Earth in the first approximation is a dipole whose poles are located next to the geographic poles of the planet. The field forms a magnetosphere that deflects the solar wind particles. They accumulate in radiation belts - two concentric areas in the form of a torus around the Earth. Near the magnetic poles, these particles can "fall out" into the atmosphere and lead to the appearance of polar shine.

According to the theory of "Magnetic Dynamo", the field is generated in the central region of the Earth, where heat creates the flow electric current In a liquid metallic core. This in turn leads to the emergence of the earth magnetic field. Convection movements in the kernel are chaotic; Magnetic poles drift and periodically change their polarity. This causes an inversion of the magnetic field of the Earth, which arise on average several times every few million years. Last inversion occurred approximately 700,000 years ago.

Magnetosphere - The area of \u200b\u200bspace around the Earth, which is formed when the flow of charged solar wind particles deviates from its initial trajectory under the influence of the magnetic field. On the side facing the Sun, the thickness of her head shock wave is about 17 km and it is located at a distance of about 90,000 km from the ground. On the night side of the planet, the magnetosphere is pulled out by purchasing a long cylindrical shape.

When charged high energy particles face the Earth's magnetosphere, the radiation belts (Van Allen belt) appear. Polar radiances occur when solar plasma reaches the atmosphere of the Earth in the region of magnetic poles.