Delhi’s air quality remained in the higher end of the “very poor” category for a second consecutive day on Monday, with a visible haze enveloping the skies in the morning hours and leading to an average 24-hour air quality index of 381 (“very poor”), according to the Central Pollution Control Board’s (CPCB) 4pm bulletin.
AQI continued to rise through the evening, and by the end of the day, it was 387 at 10pm, data showed.
Experts, pointing out that the 4pm AQI was just one point lower than the previous day’s, said meteorological conditions continued to remain unfavorable for the dispersion of pollutants, with calm winds and low temperatures trapping pollutants locally.
Mahesh Palawat, vice president at Skymet meteorology, said winds were becoming calm overnight, with strong winds missing even during the day over the past two days.
“On Monday, the wind direction was variable, but predominantly southeasterly. Light winds of around 5-8 km/hr can take place during the day, but conditions are mostly calm. No significant change in wind speed is likely for the next 2-3 days, barring a marginal increase in wind speed on Wednesday,” he said.
Forecasts say Delhi’s AQI is likely to remain “very poor” for the next three days, with no significant change in meteorological conditions likely. CPCB classifies AQI between 201 and 300 as “poor”, between 301 and 400 as “very poor”, and over 400 as “severe”.
CPCB calculated the day’s AQI based on data from 39 out of 40 local air quality monitoring stations, where PM2.5 (particulate matter with a diameter of 2.5 microns or less) was the dominant pollutant in the air. Of these stations, at least 12 had AQI readings in the “severe” category at 10pm, with Anand Vihar the worst off, at 444, followed by Jahangirpuri, at 431.
The India Meteorological Department (IMD) forecast that clear skies would persist in Delhi, with “smog/mist” likely in the morning and at night. A Met official said the lowest visibility on Monday was around 1,300 metres, at Palam at around 8am, while it was around 1,500 meters at 10.30am at Safdarjung. IMD classifies it as “fog” when visibility dips below 1,000m.
fog missing
“Fog is missing so far, but there is moisture in the air due to southeasterly winds. Pollution is also high,” the IMD official said.
The Centre’s Early Warning System for Delhi (EWS) also predicted no significant change in air quality. “Delhi’s air quality is likely to be in the ‘very poor’ category from Tuesday till Thursday. The outlook for the subsequent six days shows AQI to be between very poor and severe,” EWS said in its daily bulletin on Monday.
Meanwhile, the Commission for Air Quality Management (CAQM) in NCR said it was keeping a tab on air quality in the region. “While no meeting on air quality was held on Monday, we are keeping track,” a CAQM official said.
Before last Saturday, strong winds of 10-15 km/hr, even at nighttime, were favorably impacting Delhi’s AQI, so much so that a major chunk of firecracker emissions, released on both Thursday and Friday, was almost simultaneously dispersed.
Delhi’s AQI on Diwali day (Thursday) was 328 (“very poor”), with it rising marginally to 339 (“very poor”) the next day. This was the second-lowest AQI on the day after Diwali in the past nine years, behind 2022, when the AQI was 302 that year.
On Monday, Delhi recorded a minimum temperature of 16.6°C, a degree above the normal and slightly up from 16.5°C recorded a day earlier. The maximum temperature was 32.1°C, which was two degrees above the normal and 1.1°C lower than Sunday’s maximum.
