Delhi’s AQI ‘severe’ for second day, NCR towns add PM2.5 load
Delhi’s pollution levels continued to be in the “severe” range for the second consecutive day on Wednesday, as calm winds led to the accumulation of pollutants in the region, senior scientists of the India Meteorological Department said.
Central Pollution Control Board (CPCB) recordings showed that on Wednesday, the overall Air Quality Index reading of Delhi was 407, in the “severe” zone. Delhi’s pollution level on Tuesday was also in the “severe” range, with an AQI reading of 402.
IMD officials said that the air quality is likely to remain severe on Thursday as well, after which winds will start picking up and help disperse pollutants.
“There will be a marginal improvement in winds on Thursday, but the pollution level will remain in the same range. There will be a slight improvement in air quality only from Friday,” a senior Met official said.
Data from Indian Institute of Tropical Meteorology’s Decision Support System, an air quality forecasting system, showed that on Wednesday, the maximum share of Delhi’s PM2.5 came from neighbouring NCR towns such as Ghaziabad, Sonipat, Panipat and Faridabad. PM2.5 is fine, inhalable particulate matter with diameter of 2.5 microns. It is considered the dominant pollutant in the region.
Pollution from Faridabad and Sonipat contributed to 15% of Delhi’s pollution on Wednesday, 10% of Delhi’s pollution share came from Panipat, 16% from Ghaziabad, and 14% from Bagpat. Other factors, which according to IITM scientists don’t usually contribute to Delhi pollution, contributed to 19-46% of Delhi’s pollution levels.
Among local sources, vehicular pollution continued to be the biggest factor in the Capital’s deteriorating air quality. On Wednesday, its share in pollution levels was 13% and scientists forecast the share will increase to 16% by Thursday.
Mahesh Palawat, vice-president (meteorology and climate change), Skymet Weather Services, said that the upcoming western disturbance that will impact most of north India, will help improve the city’s air quality from Friday.
“There is a forecast of rain from November 26 that should help improve the air quality,” he said.
A western disturbance refers to an area of “disturbed” or reduced air pressure, moving from the west to the east, carrying with it moisture associated with rainfall, snowfall and fog in northern India.
On the directions of the Supreme Court, the Commission for Air Quality Management in National Capital Region and Adjoining Areas on November 16 imposed a list of restrictions on polluting activities, including a ban on construction and demolition activities in Delhi-NCR, scheduled operations for thermal power plants, allowing only those industrial units that have switched to piped natural gas (PNG) to operate, and a ban on the entry of trucks carrying non-essential items into Delhi.
Over the last week, the commission has lifted these restrictions in a phased manner. On Monday, the final set of restrictions, the ban on construction activities in NCR and the ban on the entry of trucks into Delhi, were also lifted.