Context: According to a new analysis by the Centre for Science and Environment (CSE), parts of the Delhi-NCR region witnessed ground-level ozone readings exceeding the national standards on 87 out of 92 days in the summer period.
About Ground Level Ozone or Tropospheric ozone:
- Ozone (O3) high in the Earth’s atmosphere protects us from the sun’s harmful radiation. But ozone at ground level (tropospheric ozone), is an air pollutant that harms people and plants.
- Ground-level ozone is a colorless and highly irritating gas that forms just above the earth’s surface.
How ground level ozone is formed?
- It is called a “secondary” pollutant because it is produced when two primary pollutants react in sunlight and stagnant air.
- These two primary pollutants are nitrogen oxides (NOx) and volatile organic compounds (VOCs).
- These precursor primary pollutants are each produced primarily by a variety of human activities, including the burning of fossil fuels and various industrial processes. Certain types of volatile organic compounds can also be emitted from natural sources.
Impacts:
- Ground-level ozone is known to have significant effects on human health. Exposure to ozone has been linked to premature mortality and a range of morbidity health issues.
- It can significantly impact vegetation and decrease the productivity of some crops.
- It can also damage synthetic materials, cause cracks in rubber, accelerate fading of dyes, and speed deterioration of some paints and coatings.
