Context:
World Metrological Organisation (WMO) released 2023 Air Quality and Climate Bulletin recently.
Key findings:
- Heatwaves are expected to worsen with climate change.
- There is a strong link between the occurrence of heatwave events and high levels of ground-level ozone.
- High temperatures lead to increased emissions of volatile organic compounds (VOCs) from plants used in ozone formation.
- Hotter ambient temperatures also lend themselves to increased rates of atmospheric chemical reactivity that lead to increased ozone formation.
About Ground-level ozone:
- It is a colorless “secondary” pollutant
- It forms just above the earth’s surface.
- It is produced when two primary pollutants, nitrogen oxides (NOx) and VOCs react in sunlight and stagnant air.
- Exposure to high concentrations of ozone is hazardous to vegetation and human health.
- For example, ozone-induced crop losses average 4.4%–12.4% for staple food crops.
Stratospheric ozone is regarded as ‘good’ ozone since it reduces the harmful effects of ultraviolet (UV-B) radiation.
World Meteorological Organization (WMO):
- HQ: Geneva, Switzerland.
- An intergovernmental organization established by the ratification of the WMO Convention in 1950.
- Origin – International Meteorological Organization (IMO), which was established after the 1873 Vienna International Meteorological Congress.
- Members – 193 Member States and Territories (India is a member)
- It is a specialized agency of the United Nations for meteorology (weather and climate), operational hydrology and related geophysical sciences.
- Supreme body – World Meteorological Congress.
- Annual reports – State of the Global Climate report, WMO Air Quality and Climate Bulletin etc.
Source: Business Standard
Previous Year Question
In the context of WHO Air Quality Guidelines, consider the following statements:
1. The 24-hour mean of PM2.5 should not exceed 15 µg/m³ and annual mean of PM2.5 should not exceed 5 µg/m3.
2. In a year, the highest levels of ozone pollution occur during the periods of inclement weather.
3. PM10 can penetrate the lung barrier and enter the bloodstream.
4. Excessive ozone in the air can trigger asthma.
Which of the statements given above are correct?
[UPSC Civil Services Exam – 2022 Prelims]
(a) 1, 3 and 4
(b) 1 and 4 only
(c) 2, 3 and 4
(d) 1 and 2 only
Answer: (b)
