By Ritam Halder
NEW DELHI: Delhi and NCR, yet again, saw its air quality nosedive on Diwali, no thanks to people bursting crackers and violating a Supreme Court order allowing on green crackers to check pollution levels and was fouler than last year.
Delhi’s air quality on Wednesday, Diwali day, oscillated between “poor” and “very poor” categories as authorities warned of severe deterioration of air quality even if “partial toxic crackers” are burned compared to last year. On Thursday morning, most air quality monitoring stations across the city had “very poor” air quality.
On Wednesday, 11 areas of Delhi recorded “very poor” air quality while 24 areas recorded “poor” air quality, according to the CPCB data. An AQI between 0 and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”.
However, as Diwali evening came and despite the Supreme Court ban people all over Delhi-NCR came out and burst crackers, even though in not as large volumes as previous years, the air quality nosedived fast.
Jahangirpuri, which is arguably one of the most polluted spots in Delhi, had the highest PM10 reading at 4,499 microgram per cubic metre, according to the Delhi Pollution Control Committee real-time monitoring at 11pm and is the highest across DPCC stations on Diwali night. Wazirpur, at 1am, saw PM2.5, the finer particulate matter, touching an astronomic high of 4,659 microgram per cubic metre, which is the highest across all DPCC stations this Diwali. The permissible limit of PM10 and PM2.5 are 100 and 60 microgram per cubic metre. Other monitoring stations which showed huge spike in pollution levels were Dwarka, Okhla and Aurobindo Marg, among others.
Last year, Delhi had an air quality index of 319, which falls in the very poor category on Diwali. However, this was much better than 2016 when AQI on Diwali was 431 in severe levels and 343 in 2015. In the wee hours of the day after Diwali 2017, the AQI for Delhi was 340. In 2016, the AQI of the day after was 445 while in 2015 it was 360. This year, it’s marginally higher at 343.
The System of Air Quality and Weather Forecasting And Research had earlier forecasted worse quality air for Wednesday evening and Thursday.
“The highest levels of PM10 and PM2.5 are expected between 11am to 3am on Wednesday and Thursday. Air quality will be bad on Thursday and start to improve from Friday even if partial toxic crackers as compared to 2017 is burned,” the government-run agency had warned.
According to SAFAR, both stubble burning in surrounding states of Delhi and firecrackers are causing deterioration of air quality in the national capital. “The fire counts are seen to be very high but it is a combination of stubble burning and widespread firecrackers in that region and need not be confused with stubble only fire,” the SAFAR said in a report Wednesday.
It also said that the combination of several rapidly changing weather parameters is playing a key role in controlling the air pollution at this time.
Delhi’s air quality is expected to deteriorate to “severe plus emergency” category after Diwali, SAFAR said. “Even if 50 per cent of the total load of toxic firecrackers as compared to Diwali 2017 is added, the prevailing weather conditions will aggravate the high smoke level and make air quality to persist in severe range for at least two days on November 8 and November 9,” it said in a report.
SAFAR had also predicted that the PM10 concentration of Delhi is expected to reach 575 and PM2.5 to 378 on Thursday, recording the worst air quality of the year if fire crackers are burnt, it said.
The Indian Institute of Tropical Meteorology said the winds coming from north-westerly direction is bringing the influence of biomass burning to Delhi-NCR which may continue up to Thursday morning.
Last year, too, the Supreme Court on October 9 had banned sale of firecrackers in Delhi-National Capital Region (NCR) till October 31. However, there was no such order against buying and bursting and Delhi is solely responsible for the air it breathes due to the current weather conditions.
This year, the apex court ordered that firecrackers, other than green crackers, will not be sold in the Delhi-NCR region this Diwali and other festivals, this comes as a viable alternative for many. But on ground people wished to ignore the ban and burst and burnt anars, phuljharis and rockets.
Earlier, anticipating high pollution levels between November 1-10, the Supreme Court-appointed Environment Pollution Control and Prevention Authority (EPCA) had announced shutting down of construction activities for 10 days in the Delhi -NCR region, shutting down of coal and biomass-based industries from November 4-10, and have requested people to limit exposure to the foul air in these ten days.
“However, what is required is the participation and involvement of all of us in combating the pollution crisis, which we know is a grave health crisis. We are appealing to all citizens of NCR to join in the battle against air pollution,” it had said.
On Tuesday, EPCA also announced ban on entry of trucks into Delhi, an emergency measure under the Graded Response Action Plan, from November 8-10, keeping in mind high post-Diwali pollution levels.