Ground-level ozone pollution in Delhi-NCR
According to the recently released Central Pollution Control Board (CPCB) data, ground level ozone (O3) has started emerging as a major pollutant in Delhi on a regular basis during day time, especially after rains.
The presence of ozone has kept Delhi’s air from falling into the “good” category during this period.
Stratospheric ozone / Ground level ozone
- Be aware that ozone can be “good” or “bad” for health and the environment, depending on where it is found in the atmosphere.
- Stratospheric ozone is considered “good” because it protects living things from the sun’s ultraviolet radiation.
- Ground-level ozone, on the other hand, is considered “bad” because it can lead to a variety of health problems.
- Good ozone is naturally present in the upper atmosphere, where it forms a protective layer that shields us from the sun’s harmful ultraviolet rays.
- Tropospheric or ground-level ozone, on the other hand, is considered a harmful air pollutant because of its effects on people and the environment, and is a major component of “smog”.
- Ground level ozone is not emitted directly into the air, but is created by chemical reactions between nitrogen oxides (NOx) and volatile organic compounds (VOCs).
- It occurs when pollutants emitted by cars, power plants, industrial boilers, refineries, chemical plants and other sources react chemically in the presence of sunlight.
- Urban environments are prone to reach unhealthy levels of ozone on hot sunny days, although it can reach even higher levels during colder months.
- Ozone can be carried over long distances by the wind, so high ozone levels can be experienced even in rural areas.
Source – Times of India