Air quality drops to ‘severe’, visibility poor
NEW DELHI: A day after Sri Lankan cricketers created a buzz after walking on to the Feroz Shah Kotla Ground wearing anti-pollution masks, Delhi’s air turned fouler with a sharp rise in the level of particulates since morning.
Poor visibility was recorded in several parts of the Capital on Monday, as smog continued to engulf the city, while the mercury settled at 8.3 degrees Celsius.
The concentration of dominant pollutants PM2.5 and PM10 reached levels as high as 276 and 455 micrograms per cubic metre, respectively, by 3 pm, according to the Central Control Room for Air Quality Management of the CPCB.
The air quality index (AQI), as recorded by the Central Pollution Control Board (CPCB), also reflected the rise in the levels of these ultrafine air-borne particulates.
Around 3.30 pm, the AQI was 390 on a scale of 500, classified under ‘very poor’.
This was menacingly close to the ‘severe’ category. Sunday’s 24-hour average was 351.
Pollution levels in Delhi usually remain in the ‘very poor’ category during December.
November witnesses extremely high levels of pollution as smoke from paddy residue burning reaches the city, aggravating the situation.
However, there are phases, when such spikes are seen even during December and January, mostly due to the rapid drop in temperature and high moisture content, factors that trap particulates near the surface.
According to an IIT-KANpur study, sources of PM2.5 and PM10 during the winter months are: secondary particles like nitrates (25-30 per cent), vehicles (20-25 per cent), biomass burning (17 26 per cent), municipal solid waste burning (9-8 per cent) and to a lesser extent soil and road dust.
The development comes after the National Green Tribunal (NGT) on Monday came down heavily on the Delhi government for not filing a comprehensive action plan on ways to deal with severe air pollution in the city.
Meanwhile, the Meteorological Department recorded that at 8:30 am visibility had dropped to 700 m at the Safdarjung Observatory, while the Palam station registered it at 900 m.
Any reading that falls below the average figure of 1,000 m, during fog, is considered poor, a MET official said.
The weatherman has forecast a partly clear sky later in the day and mist for Tuesday morning.
“The minimum temperature recorded at the other stations was – Palam (10 degrees Celsius), Ayanagar (8.5), Lodhi Road (8.3) and Ridge (8.8),” MET officials said.