The atmosphere of Earth is the gas cover surrounding the planet. It consists of several layers, certain temperature and other conditions are characteristic of each of which. Its internal surface borders on the hydrosphere and bark, and external — on a near-earth part of space.
Instruction
1. In the lower part of the atmosphere which is called the troposphere, about 4/5 all mass of the air consisting of nitrogen (78%), oxygen (21%), argon (less than 1%) and carbon dioxide (0.03%) are concentrated. Other gases, such as helium, hydrogen, neon, ozone and krypton, make thousand shares of percent.
2. Troposphere height - about 10-15 km, temperature falls on average on 0.6 °C each 100 m here. In this layer there is practically all water vapor, and almost all clouds are formed. The turbulence is most strongly developed near the earth's surface and also in jet currents of the top part of the troposphere.
3. Air pressure on the upper bound of the troposphere is 5-8 times less, than on lower. In this layer there take place the processes which are crucial for formation of climate and weather on the earth's surface. Over different latitudes height of the troposphere is not identical, over the equator — about 15 km, over poles — to 9 km, and in midlatitudes — 10-12 km.
4. The stratosphere is over the troposphere, the transitional layer between them is called tropopauzy. The stratosphere stretches to 50-55 km over the Earth's surface, temperature grows together with height here. In this layer it is insignificant a little water vapor, but at the height of 20-25 km the nacreous clouds consisting of the overcooled water drops are sometimes observed. Here atmospheric ozone contains, and growth of temperature is explained by its absorption of solar radiation.
5. Over a stratosphere the mesosphere layer is located, it stretches approximately to 80 km. In it temperature falls with height to several dozen degrees below zero owing to what the turbulence is strongly developed. On the upper bound of this layer pressure of air is 200 times less, than on the Earth's surface.
6. In the troposphere, a stratosphere and the mesosphere about 99.5% of all mass of air are concentrated, in the top layers there is only its minute quantity. Above the mesosphere the thermosphere of which very high temperatures are characteristic is located. It is divided into two layers: an ionosphere which stretches to heights about one thousand kilometers, and the exosphere passing into a terrestrial crown.
7. In an ionosphere the maintenance of ions is many times more, than in underlying layers, they represent the loaded atoms of oxygen and a molecule of oxide of nitrogen, there are also free electrons. Temperature is very high here, at distance about 800 km from the Earth's surface it reaches 1000 °C.
8. The exosphere comes to an end together with the terrestrial atmosphere at the height about 2000-3000 km where hydrogen forms a terrestrial crown which stretches more than for 20,000 km. Gas density it is insignificant here it is small, only about 1000 particles are the share of 1 cubic cm.