Context
- The air quality in Delhi was registered to be in ‘severe category’ in various areas. The condition is attributed to the Smog formation in the capital.
Highlights regarding air pollution
The Ministry of Earth Sciences” air quality monitor, SAFAR, said three major factors are responsible for this situation
- secondary particle formation
- extremely calm local surface winds
- stubble burning-related intrusion.
- Due to a high moisture content, humidity has touched a new high and the air holding capacity has increased under such cool conditions, triggering rapid secondary fine particulate formation.
What is SAFAR?
- It is an initiative of Ministry of Earth Sciences (MoES), Govt. of India.
- It is a major national initiative named as "System of Air Quality and Weather Forecasting and Research", for greater metropolitan cities of India to provide location specific information on air quality in near real time.
- It forecasts 1-3 days in advance for the first time in India.
- The SAFAR system is developed by Indian Institute of Tropical Meteorology, Pune, along with ESSO partner institutions namely India Meteorological Department (IMD) and National Centre for Medium Range Weather Forecasting (NCMRWF).
What is Smog?
- Smog is air pollution that reduces visibility.
- The term "smog" was first used in the early 1900s to describe a mix of smoke and fog.
Types of Smog
- Photochemical smog-Photochemical smog, is also known as “Los Angeles smog”.It is produced when sunlight reacts with nitrogen oxides and at least one volatile organic compound (VOC) in the atmosphere.
- Sulfurous smog- It is also called “London smog,”, which results from a high concentration of sulfur oxides in the air and is caused by the use of sulfur-bearing fossil fuels particularly coal.
