After rain, the air quality in Delhi improves

Because of the rain and the favorable wind speed brought about by the western disturbance that affected northwest India, the air quality in Delhi and the surrounding regions somewhat improved.

The main meteorological station in the nation’s capital, Safdarjung Observatory, reported 7.2 mm of rain on Monday till 8:30 p.m.

The dispersal of pollutants was aided by the wind speed increasing to 20 km/h, according to an India Meteorological Department officer.

The air quality index (AQI) for Delhi was better on Tuesday at 8 am, at 365, than it was on Monday at 4 pm, at 395. The average of the values collected over the previous 24 hours is the AQI at any particular moment.

The 24-hour average AQI was 395 on Sunday, 389 on Saturday, 415 on Friday, 390 on Thursday, 394 on Wednesday, 365 on Tuesday, 348 on Monday, and 301 on November 19. The readings were taken at 4 p.m. every day.

An AQI of 0–50 is regarded as “good,” 51–100 as “satisfactory,” 101–200 as “moderate,” 201–300 as “poor,” 301–400 as “very poor,” 401–450 as “severe,” and 450 and above as “severe-plus.”

A dense layer of fog engulfed Delhi earlier on Monday, limiting visibility at the Safdarjung Observatory to only 600 meters. The Indira Gandhi International Airport had 800 meters of visibility.

Thus far in November, the nation’s capital has had ten days with very poor air quality. In November of last year, the city recorded only three days with terrible air quality; in November of 2021, it recorded twelve days, the most in the month since the Central Pollution Control Board (CPCB) started keeping track of such days.

The CPCB reports that there were nine of these days in November 2020, seven in 2019; five in 2018; seven in 2017; ten in 2016; and six in 2015.

A collaborative investigation between the Indian Institute of Technology-Kanpur and the Delhi government found that burning biomass was the main cause of the foul air in Delhi, accounting for between 31 and 51 percent of the capital’s recent air pollution.

The environment minister for Delhi, Gopal Rai, has given the relevant authorities and ministries stern instructions to enforce restrictions on cars that emit pollutants and to monitor the rising number of biomass burning occurrences.