What Causes Smog?
...zone, which is a key ingredient of urban smog.” (http://www.cbc.ca/stories/2001/06/27/sci-tech/fireworks_smog010627) For example, after doing the fireworks on the festivals, people can easily see the smog over the sky. Therefore, the ground-level ozone, which is a main element of the smog, can be generated by fireworks. Secondly, using vehicles can cause smog. There are a lot of nitrogen oxides coming out from the vehicle tail pipes. In New Scientist, Hogan states that nitrogen oxides trigger smog production. (Feb 7, 2004, P.23) Furthermore, according to Derek Elsom, “Ozone is created when nitrogen oxides and VOCs emitted by traffic, power stations and other polluting activities react chemically in the presence of sunlight.” (P.9) Therefore, the smog can also be caused by nitrogen oxides which are produced by vehicles. Finally, smog can be caused by electricity generating. When the electricity is generated, three substances will be produced, which are Nitrogen oxides, Sulphur dioxide, and Carbon dioxide. These three substances are all major contributor to smog. (ht...