Combustion of fossil fuels produces air pollutants, such as nitrogen oxides,  sulphur dioxide, volatile organic compounds.They also produces greenhouse gases like CO2.

Affects :
itrogen oxides,  sulphur dioxide , volatile organic compounds pollute the air and are responsible for acid rain in many areas.
Greenhouse gases like carbon dioxide and methane traps the heat of sun of the surface of earth and do not allow them to reflect back in space, resulting as constant increase of earth's temperature and due to which polar caps are melting and sea level is rising higher.

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