How do vehicular emissions contribute to smog?

Vehicular emissions contribute to smog by releasing pollutants like nitrogen oxides and volatile organic compounds into the atmosphere.

Vehicles, particularly those powered by fossil fuels, emit a variety of pollutants that contribute to the formation of smog. The primary culprits are nitrogen oxides (NOx) and volatile organic compounds (VOCs). When these pollutants react with sunlight, they form ground-level ozone, a key component of smog.

Nitrogen oxides are produced during the combustion process in a vehicle's engine. High temperatures cause nitrogen and oxygen in the air to combine and form various nitrogen oxides. These gases are not only harmful to human health, but also play a significant role in the formation of smog.

Volatile organic compounds, on the other hand, are released from a variety of sources, including vehicle exhausts, fuel evaporation, and the breakdown of certain chemicals used in vehicle manufacturing. These compounds react with nitrogen oxides in the presence of sunlight to form ozone.

Ozone is a harmful air pollutant and a significant component of smog. While ozone high up in the atmosphere protects us from the sun's harmful ultraviolet rays, at ground level it can cause a variety of health problems, including respiratory issues and eye irritation. It can also damage crops and other vegetation.

In addition to nitrogen oxides and volatile organic compounds, vehicles also emit particulate matter, which contributes to the visible haze characteristic of smog. Particulate matter is made up of tiny particles of dust, soot, and other substances, and can be harmful when inhaled.

In summary, vehicular emissions contribute to smog through the release of nitrogen oxides and volatile organic compounds, which react with sunlight to form ozone. This, along with the emission of particulate matter, results in the formation of smog. The reduction of these emissions is therefore crucial in the fight against air pollution and the associated health and environmental impacts.