A few months ago, my country experienced above-average rainfall, which caused flooding in several areas. One morning, on my way to work, I suddenly noticed the clarity in the atmosphere. The mountains and trees looked so bright and clean that it was evident the rainfall had created a beautiful transformation.
Pollutants
According to the Massachusetts Institute of Technology (MIT), as a raindrop falls through the atmosphere, it can attract tens to hundreds of tiny aerosol particles to its surface before reaching the ground. This process, known as coagulation, is a natural phenomenon that helps clear the air of pollutants such as soot, sulfates, and organic particles. Precipitation, along with other forms of wet deposition like snow, fog droplets, and clouds, improves air quality by removing pollen and other impurities from the atmosphere.
Smog
Smog is a type of air pollution that reduces visibility. According to National Geographic, the most common form of smog is photochemical smog. This type of smog is created when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) present in the atmosphere. Nitrogen oxides are emitted from car exhaust, coal power plants, and factory emissions. VOCs are released from sources such as gasoline, paints, and various cleaning solvents. When sunlight interacts with these chemicals, it produces airborne particles and ground-level ozone, which together form smog. Without sufficient precipitation to clear these pollutants, humans and animals alike inhale these hazardous particles. Additionally, smog is harmful to plants and animals.
Big cities tend to have a significant amount of smog due to pollution from industries and vehicles. So, how can you distinguish between smog and fog?
Difference between smog and fog
In the community where I grew up, foggy mornings were commonplace, especially during certain times of the year. There were occasions when the fog was so thick that it was dangerous to drive or walk on the roads. According to National Geographic, fog forms when water vapor, or water in its gaseous state, condenses. During this process, water vapor molecules combine to create tiny liquid water droplets that hang in the air. It is these tiny droplets that make fog visible, as water vapor itself is invisible.
Fog occurs when the humidity is extremely high. A significant amount of water vapor must be present in the air for fog to develop. Additionally, dust or some form of air pollution is necessary for fog formation, as water vapor condenses around these microscopic solid particles. There are different types of fog. Typically, fog appears white, while smog is gray and contains many tiny aerosol particles.
I don’t enjoy heavy rain, especially when it happens frequently. However, I recognize that rain benefits the environment in many ways. It replenishes our water sources, nourishes plants, and supports animals and ecosystems. Groundwater, rivers, and lakes are all replenished by rain. I find the sound of raindrops to be therapeutic. Although rain can have negative effects, such as causing flooding, one cannot deny the beauty of nature and the freshness of the air after a good rainfall.
Big cities tend to have a significant amount of smog due to pollution from industries and vehicles.
