Oxygen (O2):

• All living organisms inhale Or No life is possible without this gas.
• It can combine with all other elements and thus can form different compounds.
• It is indispensable for combustion.

Nitrogen (N2):

• Its main function in the atmosphere is to dilute oxygen and regulate combustion.
• Indirectly, it aids oxidation of different KINDS.

Carbon Dioxide (CO2):

• Plants inhale this gas.
• Green plants utilize CO2 in photosynthesis and prepare their own food.
• It is of great climatic significance because it efficiently absorbs heat from the upper atmosphere.
• It influences the flow of energy through the atmosphere because CO returns ALMOST half of the absorbed heat back to the earth.

During the past century, large scale fossil fuel burning has increased the concentration of CO, in the air. Ultimately, this has resulted in the warming of the lower atmosphere.

Ozone (O3):

This triatomic form of oxygen is the most efficient absorber of the scorching ultra-violet radiation from the sun. The ozonosphere protects us from the ill-effects of excessive quantities of UV rays. The composition of the atmosphere varies with height, latitude and time.

The light gases, especially helium and hydrogen, are found in abundance in the upper atmosphere. Water vapour constitutes almost 4% of the atmosphere by VOLUME, only near the surface. Above 10-12 km, it is nearly absent. Ozone is found mainly between 15-35 km, in the Troposphere.

Ozone and water vapour are also the two gases whose concentrations in the atmosphere vary with latitude and season. Ozone content is low over the Equator (0°). It is high over latitudes north of 50°N, that too mostly during the SPRING season.

Oxygen (O2):

Nitrogen (N2):

Carbon Dioxide (CO2):

During the past century, large scale fossil fuel burning has increased the concentration of CO, in the air. Ultimately, this has resulted in the warming of the lower atmosphere.

Ozone (O3):

This triatomic form of oxygen is the most efficient absorber of the scorching ultra-violet radiation from the sun. The ozonosphere protects us from the ill-effects of excessive quantities of UV rays. The composition of the atmosphere varies with height, latitude and time.

The light gases, especially helium and hydrogen, are found in abundance in the upper atmosphere. Water vapour constitutes almost 4% of the atmosphere by volume, only near the surface. Above 10-12 km, it is nearly absent. Ozone is found mainly between 15-35 km, in the Troposphere.

Ozone and water vapour are also the two gases whose concentrations in the atmosphere vary with latitude and season. Ozone content is low over the Equator (0°). It is high over latitudes north of 50°N, that too mostly during the spring season.