The Process Of Air Pollution

In the past decade, China with the largest economy in the world has seen the rise of acute carbon emissions in the atmosphere. With the advancement of technology, major cities in China, like Hong Kong and Beijing have been heavily plagued with smog and the culture of wearing nose masks has since been the norm long before the Corona virus pandemic hit the globe.
In Nigeria, Warri, a major oil producing city has been also plagued with smog in recent times as most mornings, the air can be seen to be thick and dense, making buildings hardly visible against a backdrop of thick smog especially during the wet season.

 However, like water bodies, the atmosphere can cleanse itself as long as it is not overloaded and overwhelmed with pollutants produced in large quantities and concentrations. Cities often accumulate pollutants both because they produce them in such large amounts and because cities are often located in river valleys along base or on level areas beside mountains. Most of these areas are often subject to temperature inversions.

This is an atmospheric condition in which a layer of warm air lies above a layer of cold air. The cold air is heavier hence it  remains near the ground and pollutants accumulate in it. In a normal situation, air near the ground is warmed by heat radiated from the ground. The air rises, causing the pollutants upward to dissipated by winds in the upper air. When an inversion is present, the warm air that lies above the cold air is like a ceiling. It traps the pollutant, which can accumulate to dangerous levels of concentration if the inversion remains for a long time.

In times past, Denver, Colorado in the United States had often times declared a state of emergency due to increased levels of air pollution occurring as a result of temperature inversions. At such times, however, only strong mountain winds have been able to break up the inversions and allow the polluted air to move away, thus, saving the city from acute air pollution. This process of temperature inversions occurring on a frequent basis in past decades,  and its accumulated effects over the years has given rise to global warming.