Delhi AQI improves, relief likely to be short-lived; GRAP 3 rolled back | See curbs lifted

Delhi woke up to relatively clearer sky on Saturday morning with the city recording an overall Air Quality Index (AQI) of 235 at 8 am, marking a significant improvement after weeks of ‘very poor’ to 'severe' category air.

Nine recording stations logged air quality in the moderate category, according to .data on Central Pollution Control Board (CPCB). These included Mandir Marg with AQI of 128, followed by Bawana (145) and IGI Airport T3 (148). Jahangirpuri station recorded the worst AQI of 309, followed by Nehru Nagar (297) and Sirifort (289).

Delhi's overall AQI on Friday stood at 236, compared to 380 recorded the previous day, an improvement driven by strong surface winds of 15-20km per hour.

However, the respite might be short lived as Air Quality Early Warning System (AQEWS) forecast shows air quality will return to “very poor” from Sunday through Tuesday, HT reported earlier. “The outlook for the subsequent six days is that the air quality is likely to be in the very poor category,” the AQEWS bulletin stated, indicating Delhi will face at least eight consecutive days of very poor air beginning Sunday.

As air quality showed improvement in the national capital on Friday, the Commission for Air Quality Management (CAQM) revoked Stage-III measures of the Graded Response Action Plan (GRAP).

However, the CAQM clarified that preventive and regulatory actions prescribed under GRAP Stages I and II will continue to remain in force to ensure that air quality does not deteriorate again, as winter weather continues to pose challenges. Authorities have urged residents to follow the citizen guidelines prescribed under these stages.

The rollback of the third stage of the graded response action plan (Grap) allows private construction and demolition activities, mining and allied operations to resume immediately. Restrictions on older BS-3 petrol and BS-4 diesel vehicles operating in the region are also lifted, along with other vehicular curbs imposed under Stage 3.

CAQM justified the rollback by citing the “prevailing trend of air quality” and the significant improvement from Thursday’s reading.

“The AQI of Delhi which was recorded as 380 yesterday has significantly improved and recorded 236 today at 4pm, exhibiting a declining trend,” the commission said in a statement on Friday evening, adding that restrictions under Stage 1 and Stage 2 will remain in place.

Under Stage 2, the entry of interstate buses from NCR states — other than electric, CNG or BS-6 diesel vehicles — remains prohibited in Delhi.

While surface winds helped clear up fog in Delhi on Friday, the India Meteorological Department (IMD) has issued a yellow alert for moderate to dense fog over the weekend.

Icy-cold northwesterly winds will lead to a sustained drop in minimum temperature, expected to dip by 2-3 degrees Celsius over the weekend. The minimum temperature on Friday stood at 9.1 degrees Celsius, two degrees above normal, but is forecast to hover between 6 and 8 degrees Celsius on Saturday and Sunday, IMD officials said.

“We are now seeing cold northwesterly winds blow and wind speed should remain consistent for another 1-2 days,” said Mahesh Palawat, vice president at Skymet Weather, adding that minimum temperatures will continue falling as no western disturbance is expected until the second week of January.