Composition and Structure of Atmosphere Test - 1

The troposphere is the lowermost layer of the atmosphere. Its average height is 13 km and extends roughly to a height of 8 km near the poles and about 18 km at the equator.

The volume of other gases is constant but the volume of carbon dioxide has been rising in the past few decades mainly because of the burning of fossil fuels. 

Exosphere: This is the outermost layer of the atmosphere. It extends from about 375 miles (600 km) to 6,200 miles (10,000 km ) above the earth. In this layer, atoms and molecules escape into space and satellites orbit the earth.

Carbon dioxide is meteorologically a very important gas as it is transparent to the incoming solar radiation but opaque to the outgoing terrestrial radiation. 

Dust and salt particles act as hygroscopic nuclei around which water vapour condenses to produce clouds. 

The exosphere is the highest layer but very little is known about it. Whatever contents are there, these are extremely rarefied in this layer, and it gradually merges with outer space. Although all layers of the atmosphere must be exercising influence on us, geographers are concerned with the first two layers of the atmosphere.

Water vapour acts like a blanket allowing the earth neither to become too cold nor too hot. 

The layer of the atmosphere which reflects the radio waves back to the earth is called Ionosphere.

The inert gas argon (Ar) is the third most abundant gas at 0.93%.

A layer of gas surrounding the Earth is called as atmosphere, which extends up to a height of about 1,600 km. The atmosphere is mainly composed of nitrogen which makes up to 78% of the air in the atmosphere.