Delhi witnesses poor air quality, likely to gradually deteriorate
Forecasts show a gradual deterioration in air quality is expected in the next 24 hours, with the AQI touching the ‘very poor’ category later today and possibly touching ‘severe’ by Monday
Delhi’s air quality was in the lower half of the ‘poor’ category on Sunday -- aided by strong winds over the last two days and light showers across the city. The 24-hour average air quality index (AQI) for Delhi was 202 (poor) at 7 am this morning, a slight improvement from Saturday’s 4 pm reading of 220 (poor). Forecasts show a gradual deterioration in air quality is expected in the next 24 hours, with the AQI touching the ‘very poor’ category later today and possibly touching ‘severe’ by Monday, as firecracker emissions possibly get added into the atmosphere.
Central Pollution Control Board data from 2016 onwards shows that the AQI has increased the day-after-Diwali every year, with the exception of last year, when strong winds helped disperse firecracker emissions. While the AQI remained in the ‘very poor’ category on the day of Diwali as well as the next day in 2022, strong winds on the day after Diwali helped in dispersing pollutants, possibly negating the impact of firecrackers burst in Delhi NCR during the festival.
“The air quality is likely to deteriorate and will reach in ‘Very Poor’ category on November 12. The air quality is likely to reach in ‘Severe’ category from November 13 to 14. For the subsequent six days, the air quality is likely to remain in Severe to Very Poor category,” said a forecast issued by the Early Warning System (EWS) for Delhi.
IMD data shows while wind speeds are expected to be between 5-10 km/hr today, they may become calm in the early hours of Monday.
“Wind speeds were strong, touching up to 15 km/hr on Saturday. Good wind speed - upto 10 km/hr, is expected today as well, before wind speeds start to dip again from Monday,” said Kuldeep Srivastava, scientist at IMD.
“The trend of calm winds at night and a slight increase in speed in the afternoon may once again be seen from Monday,” He added.
Calm winds can lead to trapping of pollutants, leading to accumulation of smoke in the atmosphere.
The predominantly wind direction will also be northwesterly during the next three days - a wind direction that brings stubble smoke from Punjab and Haryana, towards Delhi.
Farm fire events have shown a dip in the last two days across northern India, largely due to rains. Only 104 fires were recorded in Punjab on Saturday and six on Friday. The count on Thursday was 639. Similarly, Haryana recorded 27 fires on Saturday, but none on Friday. The count was 27 on Thursday too.
Like last year too, there is a complete ban on all types of firecrackers in the capital. However, similar to the past few years, this ban gets flouted, with thousands bursting firecrackers illegally - contributing towards deteriorating air quality and spikes in PM 2.5 concentration that can go up to 20 or 30 times the permissible PM 2.5 limits.