Delhi air quality enters poor category with AQI at 230

Delhi’s average air quality index reached 230 at 8:15 a.m. on October 21, putting the capital in the poor category after a moderate reading of 179 the previous day, according to hourly readings published by the Central Pollution Control Board. Forty-one of the city’s 56 active monitoring stations recorded poor or worse air quality. The poor category covers AQI readings from 201 to 300. Pusa recorded 318, a very poor reading and the highest reported in Delhi that morning. Station-level readings also showed poor air in several other areas, including Bawana and Dwarka Sector 8. The Air Quality Early Warning System forecast that conditions would remain poor through October 23. The Indian Institute of Tropical Meteorology separately forecast poor air quality for six days from October 21. On October 20, Delhi’s AQI was 179, in the moderate category, after readings had risen from 139 on October 19. The deterioration coincided with falling temperatures and weather conditions that can limit the dispersal of pollutants. The Indian Institute of Tropical Meteorology’s Decision Support System identified transport as the largest source among those it tracked, accounting for 23.02% of...