Smog is basically derived from the merging of two words; smoke and fog. Smog is also used to describe the type of fog which has smoke or soot in it. Smog is a yellowish or blackish fog formed mainly by a mixture of pollutants in the atmosphere which consists of fine particles and ground-level ozone. Smog which occurs mainly because of air pollution can also be defined as a mixture of various gases with dust and water vapor. Smog also refers to hazy air that makes breathing difficult.
How is it Formed?
The atmospheric pollutants or gases that form smog are released in the air when fuels are burnt. When sunlight and its heat react with these gases and fine particles in the atmosphere, smog is formed. It is purely caused by air pollution. Ground level ozone and fine particles are released in the air due to complex photochemical reactions between volatile organic compounds (VOC), sulfur dioxide (SO2) and nitrogen oxides (NOx).
Smog is produced by a set of complex photochemical reactions involving volatile organic compounds (VOCs), nitrogen oxides and sunlight, which form ground-level ozone.
Smog-forming pollutants come from many sources such as automobile exhaust, power plants, factories, and many consumer products, including paint, hairspray, charcoal starter fluid, chemical solvents, and even plastic popcorn packaging.
In typical urban areas, at least half of the smog precursors come from cars, buses, trucks, and boats.
Major smog occurrences often are linked to heavy motor vehicle traffic, high temperatures, sunshine, and calm winds. Weather and geography affect the location and severity of smog. Because temperature regulates the length of time it takes for smog to form, smog can occur more quickly and be more severe on a hot, sunny day.
When temperature inversions occur (that is, when warm air stays near the ground instead of rising) and the wind is calm, smog may remain trapped over a city for days. As traffic and other sources add more pollutants to the air, the smog gets worse. This situation occurs frequently in Salt Lake City, Utah.
Ironically, smog is often more severe farther away from the sources of pollution, because the chemical reactions that causes smog take place in the atmosphere while pollutants are drifting on the wind.
How can it affect my health?
Exposure to smog can lead to several different types of short-term health problems due to its ozone content. These include:
Unfortunately, in Pakistan there is no any air quality monitoring facility so that we can timely aware the masses about the dangerous effects of air pollution, in this regard Government of Pakistan should take necessary steps.
It is the fundamental right of every Pakistani to enjoy a clean and healthy environment. It is the right of every working man and woman to be able to get to work and home again without getting sick. It is the right of every child to play outdoors without acquiring respiratory disease.