From UPSC perspective, the following things are important :
Prelims level : World Air Quality Report
Mains level : Air pollution in Delhi
Delhi remained the most polluted capital city in the world but India, on the whole, had improved its average annual PM 2.5 (particulate matter) levels higher in 2020 than in 2019, according to a report from World Air Quality Report Air.
Try this question from CS Mains 2015:
Q.Mumbai, Delhi and Kolkata are the three megacities of the country but air pollution is a much more serious problem in Delhi as compared to the other two. Why is this so?
World Air Quality Report
- It is released by a Swiss air quality technology company IQAir.
- IQAir is an air quality technology company that since 1963 seeks to empower individuals, organizations and communities to breathe cleaner air through information, collaboration and technology solutions.
- The 2020 Report is based on PM2.5 data from 106 countries that have been measured by ground-based monitoring stations.
Highlights of the report
- Of the 14 most polluted cities, 13 were in India.
- When ranked by cities, Hotan in China was the most polluted, with an average concentration of 110.2 µg/m³, followed by Ghaziabad in Uttar Pradesh at 106.
- Delhi’s concentration level, based primarily on data from the Central Pollution Control Board, was 84.1 µg/m³ in 2020, a 15% improvement from the 98.6 µg/m³ recorded in 2019 — a consequence of the lockdown.
- Bangladesh and Pakistan were the countries in 2020 with worse average PM 2.5 levels than India, says the report.
- China ranked 11th in the latest report, a deterioration from the 14th in the previous edition of the report. In the 2020 report, 106 countries were evaluated.