During the day, fine dust accumulates near the surface. As the surface cools at night, cold, dense air settles at the bottom with warmer air above. This forms a "lid" over the atmosphere, completely stopping vertical air circulation.

During this time, fine dust and pollutants from vehicles and factories accumulate in layers near the surface. As this stagnation worsens, fine dust concentrations rise exponentially. In this condition, temperature inversion causes further stagnation of air pollution, significantly increasing fine dust concentrations, leading to adverse health effects such as respiratory and cardiovascular diseases.