A week ahead of Diwali , a haze of pollutants shrouded the skyline in the early hours on Sunday as the Capital’s air quality index (AQI) dipped into the “poor” category, erasing the brief respite brought on by rains last week. Forecasts show that the situation is expected to worsen in the coming days, dipping into the “very poor” category in the second half of this week.
Past data shows the contribution of farm fires peaks typically in the first week of November, making it an important time of the year to capture data. It continued to deteriorate through the data, registering at 272 at 6pm, 287 by 10pm, and 290 by 11pm. It was followed by Rohini (352), Punjabi Bagh (351), Mundka (337), RK Puram (335), and Chandni Chowk at 328. Also Read I Traffic snarls, ‘frustrated’ public: Anti-pollution restrictions kick in as Delhi’s AQI turns ‘poor’ According to the Decision Support System (DSS) for air quality management in Delhi, stubble burning’s contribution to Delhi’s air pollution rose to 18.57% on Sunday, up from 5.33% on Saturday. It showed that, by 4:30pm the day’s pollution had spread only 1,100 m up from the ground, where the wind averaged 10 km/h. On a typical early-November afternoon it spreads about 1,300m up, with wind of about 13 km/h.
As a result, on Sunday afternoon, the weather worked against clearing Delhi’s air, according to an HT analysis of IMD’s weather-balloon readings from Safdarjung.
The city recorded a 24-hour average AQI of 261 (“poor”), according to the Central Pollution Control Board (CPCB)’s 4pm bulletin, worsening over 144 points from a day earlier when it registered 117 (“moderate”) category. This comes two days after heavy rains and strong winds brought respite from “poor” AQI and the city recorded an AQI of 60 (“satisfactory”) on Friday. Data from 57 of the city’s 59 monitoring stations showed that 22 recorded “very poor” air quality, with Jahangirpuri logging the worst AQI at 378 at 4pm.
To be sure, Delhi winter pollution action plan came into effect on Sunday, which bars non-Delhi vehicles below BS-VI emission standards, bans all dust-generating demolition and outdoor civil construction activities, and mandates 50% attendance in offices and work from home.
