You must have come across the problem of air pollution in Beijing, Delhi and Mumbai, and all the havoc it is causing. There are daily articles in the newspapers about the deteriorating Air Quality Index and its disastrous health effects. But how does the air get this much polluted? Why are some areas affected more and others less? Let us take a look at this topic of Air Pollution.
Composition of Air
What is the most important component of air? Oxygen, right? Well, that is what we all think, however, in reality, all the various components of air are just as important as Oxygen. Let us have a look.
|Component||% in Atmosphere||Importance|
|Nitrogen||78% – 79%||
In a broad sense, air pollution means the presence of chemicals or compounds (called pollutants) in the air which are not naturally occurring, and which lower the quality of air, and are harmful to all living things in the atmosphere. Air pollution is majorly caused due to the release of various chemicals into the atmosphere. Air pollution can be both man-made and naturally occurring.
In our current age of industrialisation and modernisation, the biggest source of air pollution is the burning of fossil fuels. For example when we burn petrol or diesel or coal to run our cars, machines, trains, power plants etc. this releases harmful pollutants into the atmosphere, endangering all living things around.
There are two major types of air pollutants, gaseous compounds and compounds in solid form. There is actually a laundry list of the various pollutants that are affecting our environment, but the few very dangerous ones are
- Carbon Monoxide
- Sulphur Oxides
- Nitrogen Oxides
- Carbon Dioxide
- Particulate Matter
- Radioactive Pollutants
Causes of Air Pollution
Air pollution can be caused by both man-made and natural causes, although the contribution by these natural causes is pretty negligible.
The main culprit of air pollution is the man-made sources of air pollution. The single most harmful source of air pollution is the unchecked burning of fossil fuels by mankind. Fossil fuels (non-renewable sources of energy such as crude oil, petrol, diesel, coal etc.) are used in almost every process of industrialization, manufacturing, transport and energy generation. In rural areas, a major source of pollution is the practice of unchecked crop burning. In moderation, this is actually a useful tool in farming but uncontrolled crop burning causes significant air pollution. Another source of man-made pollution is military resources such as nuclear arsenal and chemical weaponry.
There are a few natural sources of air pollution as well. such as forest fires, volcanic activity and methane discharged from cattle. However, the amount of air pollution caused by natural causes is minuscule when compared to the damage done by man-made causes.
Consequences of Air Pollution
- Ozone Depletion: The Ozone layer is a belt of natural gasses in the stratosphere that envelopes the planet. It protects us from harmful ultraviolet B radiation that the Sun emits. The pollutants that cause air pollution in our atmosphere are seriously damaging the ozone layer. Over the last few decades, many holes have appeared in the layer. The ozone layer above Antartica particularly has seen some very serious damage. When the ozone layer gets depleted the harmful UVB radiation reaches the surface of the earth and causes skin cancer and eye damage among humans.
- Smog: Smog is the deadly combination of Smoke and Fog. It is the greyish fog that is caused when the pollutants in the air, such as carbon particles, condense and mix with the fog. Smog is extremely harmful to humans and the entire environment. It can lead to diseases such as cold, flu, irritation of the eye, asthma and in the long term even lung cancer
- Acid Rain: Acid Rain is caused when a chemical reaction occurs between air pollutants and water and oxygen very high in the atmosphere. Pollutants such as sulphur dioxide and nitrogen oxide are water soluble and mix with the water in the atmosphere and precipitate as acid rain. The acidic nature of this rain causes severe damage to the plants, animals and the soil
Strategies to Control Air Pollution
- Use of Energy efficient appliances: Whether at the domestic level or at the industrial level, we must push for appliances that use energy efficiently, which result in complete combustion of fuel, as incomplete combustion causes air pollution.
- Shifting industries: Another possible solution to reduce the harmful effects of air pollution is to shift the manufacturing plants, factories and industries to remote areas with a low level of population. By doing so you can ensure that pollution in the urban areas decreases over time.
- Using Modern Techniques: With technology making great advancements, there are now technologies available that can help reduce the release of pollutants in the air. Air filters, scrubbers, precipitators are just a few examples.
- Shifting to Natural Gasses: Instead of using and exhausting fossil fuels, shifting to greener options is a no-brainer. For example, using CNG (compressed natural gas) instead of petrol or diesel is a great option.
Solved Examples for You
Q: Global warming is a direct result of
- an increased imbalance of gases in the atmosphere
- a decreased imbalance of gases in the atmosphere
- an increased balance of gasses in the atmosphere
- none of the above
Solution: The correct option is “a”. The atmosphere is polluted with various gaseous pollutants such as Carbon Monoxide, Sulphur Oxides etc. These pollutants are causing an imbalance of gases in the atmosphere, causing increased air pollution.