After a brief respite on Saturday, Delhi’s air quality deteriorated once again, reaching “severe” levels — this time with an AQI of 460 on a scale of 500. The concentration of particulate matter was recorded at over seven-times the norm.
This comes a day after the Delhi government deferred the rollout of the odd-even vehicle rationing scheme from November 13-17, after the National Green Tribunal refused exemptions for two-wheelers and women drivers. A government spokesperson said, “We will approach the NGT on Monday for the same.”
Hitting out at other state governments and the NGT on Sunday, the AAP government said despite it being the only authority attempting to comply with the Supreme Court-appointed Environment Pollution (Prevention and Control) Authority’s (EPCA’s) action plan, it was the one scrutinised the most.
AAP MLA and Delhi unit spokesperson Saurabh Bhardwaj said both the odd-even scheme and the increase of parking rates had been mandated by the EPCA. “After listening to all stakeholders, the Graded Response Action Plan (GRAP) has been put to test by the highest court of India. That is why it was included as an emergency response to severe pollution levels. I doubt if the NGT can review the SC’s decisions. The government of Delhi is committed to the action plan created by the SC.”
According to the GRAP, officials said the odd-even scheme is supposed to be implemented if the prevailing levels of PM 2.5 and PM10 persist for another 24 hours.
State-owned helicopter service company Pawan Hans — which has agreed to help the government in aerially sprinkling water over the city to help pollutants settle — will meet the latter on Monday. An official said, “The meeting will be at 4.30 pm. A joint-group is likely to be set up to figure out the manner in which this will be implemented.”
Why the spike?
On Saturday, the hourly graph of the Central Control Room for Air Quality Management had recorded a brief period when air quality was below emergency levels. But by Sunday afternoon, it recorded PM 2.5 and PM 10 concentrations at 478 and 713 micrograms per cubic metre. The 24-hour-safe standard for the two pollutants are 60 and 100 µg/m3 respectively.
The most dominant pollutants were PM 2.5 and CO, according to the CPCB air bulletin. These particles, too small to be seen by the naked eye, enter the lungs and the smallest can penetrate into the bloodstream, leading to long-lasting health impacts, explained the WHO.
While Delhi’s AQI was 460, the corresponding values for the rest of the national capital region were far more grim — Faridabad recorded 460, Gurgaon 460, Ghaziabad 498 and Noida 492.
CPCB and SAFAR scientists maintained that the fresh spike in pollution was triggered mainly due to the drop in inversion layer (the layer beyond which pollutants cannot disperse into the upper layer of the atmosphere), which in turn happened due to sharp drop in minimum and maximum temperatures.
A MeT department official added that substantial reduction in the city’s air pollution concentrations were likely to happen from Monday. “The windflow from Punjab and Haryana is likely to continue till Sunday. On Monday, the wind will start flowing from Delhi to Punjab and Haryana. With the influence of western disturbance approaching Delhi on Wednesday, there might be light rains. With this, the atmospheric circulation will become favourable for substantial reduction of concentration of pollutants starting Wednesday,” the official said.