The surface of the earth is divided into lithosphere, hydrosphere and atmosphere. Lithosphere is the solid portion with rocks, sails and other sediments. The hydrosphere is the solid portion with rocks, sails and other sediments. The hydrosphere includes the liquid portion consisting of oceans and waters as the atmosphere constitutes the gaseous elements and it extends up to a height of 2000km. the major components of the atmosphere are –
- Nitrogen (N2) -78.08%,
- Oxygen (O2) – 20.94%
- Argon (Ar) – 0.93%
- Carbon dioxide (CO2) – 0.03%
It also contains Carbon Monoxide, Neon, Helium, Methane, Oxides of Nitrogen, Sulphur and Particulars. Water vapor in the atmosphere varies from 0 to 4% by volume.
Layers on the Basis of Temperature:
On the basis of temperature variation, atmosphere is divided into – Troposphere, Stratosphere, Mesosphere, Thermosphere and Exosphere.
About 95% of the mass of the atmosphere is contained in the Troposphere and it is the lowest portion of the atmosphere extending up to 11km. from the earth’s surface. The layer temper remains at 0.60 c.
This layer extends up to 50km. from the earth’s surface and temperature rising 10-200c at 50 km. the layer has little water vapor. This layer contains ozone molecules absorb ultraviolet radiation from the sun and get decomposed in to oxygen atoms are highly reactive and they combine with oxygen molecules to form ozone and that heat energy is released. The upper surface of the stratosphere is called Stratopause.
The mesosphere extends above stratosphere up to 90-100 km. above the earth’s surface. There is fall and rise of temperature up to -700 c in altitude. The mesosphere decrease rapidly in temperature because of absorption of solar radiation by ozone. The upper surface of mesosphere is Mesopause.
Above the mesosphere extending up to 500km. above the earth’s surface is thermosphere. There is steady rise in temperature wish altitude.
The layer after ionosphere (thermosphere) and here there is air density is very low and outer space being after it.