NO and
 are main components producing
 in troposphere.
The life of these gases are quite short even less than 1 day.
Combustion of fossil fuel is the largest source of
 .
The quantities are sufficient enough to affect the quality of atmospheric air.
Combustion of fossil fuel is the largest source of around 22 Mt/yr.
Stationary source contribution is around 13 Mt/yr.
Contribution of emission by biomass is quite small.
Due to combustion, there is a four fold increase in the tropospheric .
The major sources of emission and their contributions are depicted in the next section. |
