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A brief note on Smog causes

Coal combustion emissions, vehicular emissions, industrial emissions, forest and agricultural fires, and photochemical reactions of these emissions all contribute to man-made smog.

The Smog, also known as smoke fog, is a type of severe air pollution. The term “smog,” which is a contraction (portmanteau) of the words smoke and fog, was coined in the early twentieth century. Because of its opacity and odour, smoky fog is referred to as. The term was originally intended to refer to what was known as pea soup fog, a common and serious problem in London from the nineteenth to the mid-twentieth centuries. Nitrogen oxides, sulphur oxides, ozone, smoke, and other particulates contribute to this type of visible air pollution. Coal combustion emissions, vehicular emissions, industrial emissions, forest and agricultural fires, and photochemical reactions of these emissions all contribute to man-made smog.

What is Smog?

Smog is a type of air pollution that impairs visibility. The term “smog” was coined in the early twentieth century as a contraction (portmanteau) of the words smoke and fog to describe smoky fog because of its opacity and odour.

The term was originally intended to refer to what was known as pea soup fog, a common and serious problem in London from the nineteenth to the mid-twentieth centuries.

Nitrogen oxides, sulphur oxides, ozone, smoke, and other particles make up this type of visible air pollution. Coal combustion emissions, vehicular emissions, industrial emissions, forest and agricultural fires, and photochemical reactions of these emissions all contribute to man-made smog.

What are the Effects of Smog?

  • Smog is a mixture of air pollutants that can endanger human health, harm the environment, and even cause property damage.
  • Smog can cause or exacerbate health problems such as asthma, emphysema, chronic bronchitis, and other respiratory issues, as well as eye irritation and decreased resistance to colds and lung infections.
  • Smog ozone also inhibits plant growth and can cause widespread crop and forest damage.

Causes of Smog

There are various causes of smog which are given below:

Using Coal as a Fuel

Coal, one of the most important primary fossil fuels, is a solid carbon-rich material that is usually brown or black in colour and occurs most commonly in stratified sedimentary deposits.Coal is defined as having more than 50% carbonaceous matter by weight (or 70% by volume) produced by the compaction and hardening of altered plant remains, namely peat deposits. Different types of coal exist due to differences in plant material (coal type), degree of coalification (coal rank), and impurity range (coal grade). 

Although the majority of coals are found in stratified sedimentary deposits, the deposits may later be subjected to elevated temperatures and pressures caused by igneous intrusions or deformation during orogenesis (i.e., mountain-building processes), resulting in the formation of anthracite and even graphite. Although the concentration of carbon in the Earth’s crust is less than 0.1 percent by weight, it is necessary for life and is the primary source of energy for humans.

Vehicular and Industrial Emissions

Vehicle emissions are classified as either direct ‘tailpipe’ emissions – formed by fuel combustion in conventional vehicles – or indirect by-products of gaseous reactions in the atmosphere. Below is a list of both types:

Carbon dioxide

Carbon dioxide (CO2) is a major component of a vehicle’s tailpipe emissions. Motor vehicles, as an end product of any fuel combustion process, are estimated to contribute nearly 24 percent of the world’s direct CO2 emissions today. While these may not pose any immediate health risks, their continued accumulation catalyses global warming, exacerbating climate change.

Carbon monoxide

Carbon monoxide (CO) is a highly toxic gas that is colourless and odourless and is produced by the incomplete combustion of fossil fuels. This is extremely harmful to one’s health because it impairs the body’s ability to absorb oxygen. According to studies, vehicular emissions are the primary source of CO in highly polluted cities like New Delhi, which fell by nearly 86 percent during the Covid-19 lockdown due to restrictions on vehicular movement.

Nitrous oxide

Nitrous oxide (NOx) is produced by the high-temperature combustion of fossil fuels and contributes to the formation of ozone. Indian cities such as New Delhi, Bangalore, Mumbai, and Kolkata have some of the highest NOx levels in the country, which are entirely due to vehicular pollution. Ground-level ozone is caused by an excess of NOx. Although not directly emitted by transportation, the creation of this lethal secondary gas is strongly linked to respiratory diseases and asthma.

Particulate matter

Particulate matter (PM) is a combination of solid and liquid pollutants that are easily inhaled, such as dust, soot, and smoke. Depending on their diameter, these are classified as PM 2.5 or PM 10. These could be formed directly as a result of fuel combustion or indirectly as a result of complex atmospheric reactions. 

The transportation sector is responsible for one-third of India’s PM pollution and 20-35 percent of PM 2.5 pollution in Indian cities.

Conclusion 

The Smog, also known as smoke fog, is a type of severe air pollution. The term “smog,” which is a contraction of the words smoke and fog, was coined in the early twentieth century. The term “smog” was coined in the early twentieth century as a contraction of the words smoke and fog to describe smoky fog because of its opacity and odour. Smog is a mixture of air pollutants that can endanger human health, harm the environment, and even cause property damage. Carbon monoxide is a highly toxic gas that is colourless and odourless and is produced by the incomplete combustion of fossil fuels. Nitrous oxide is produced by the high-temperature combustion of fossil fuels and contributes to the formation of ozone. 

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