Air pollution has direct impact on climate change, the major pollutants being Greenhouse gases: Carbon Dioxide, Methane, Chloro Fluoro Carbons (CFCs) and Nitrous Oxide. These gases allow sunlight to come in but block some of the infrared radiation (carrying heat back into the atmosphere) from leaving the earth's surface. This leads to development of concentrated heat zones on the earth surface. Development of concentrated heat zones causes turbulence in air currents and ocean currents leading to increased precipitation, floods, storms, cyclones and droughts, frequently witnessed phenomena in recent years.

Carbon Dioxide is the most prominent Greenhouse gas. The concentration of CO2 has increased by over 20 per cent post-industrial revolution. While the United States is the largest producer of global CO2 emissions (23%), India's share is relatively lower at 4%.

Particulate matters in the atmosphere also contribute to climate changes. Among particulate matters, black carbon has a warming effect while nitrates and sulphates have a cooling effect on the climate. However, higher concentration of nitrates and sulphates shields the effect of particulate matters on climate change. Natural gas is one of the cleanest conventional fuels, which can help improve the quality of air, especially when used in place of other more polluting energy sources. Natural gas combustion results in virtually no atmospheric emissions of sulphur dioxide or small particulate matter, and far lower emissions of carbon monoxide, reactive hydrocarbons, nitrogen oxides and carbon dioxide.

The two principal air pollution issues are acid rain and carbon monoxide (CO)/ozone pollution levels. Reducing high ozone pollution levels in urban areas requires the reduction of reactive hydrocarbons and sometimes nitrogen oxide emissions. Besides being a contributor to ozone formation, CO is a health hazard. All these pollutants are released into the atmosphere by the combustion of some fossil fuels in stationary sources such as industrial boilers and power plants, and in automobiles. Natural gas is the solution to these pollution problems. Advanced natural gas-fuelled vehicles have the potential to reduce carbon monoxide emissions by 90 per cent and reactive hydrocarbon emissions by 85 per cent compared with gasoline vehicles. It is also possible to burn natural gas simultaneously with less environment-attractive fuels.

Source:IEA