NEW DELHI: Delhi’s air quality improved marginally to ‘very poor,’ on Monday, as winds picked up slightly. Air quality is likely to remain so over the next two days owing to easterly winds blowing in the city, carrying moisture that further allows trapping of pollutants.
Delhi’s overall air quality on Monday was 387 in the ‘upper end of the very poor’ zone, as against 404 on Sunday in the ‘severe’ range, as per the Central Pollution Control Board (CPCB). It was the first severe air quality day recorded this January.
Officials in the India Meteorological Department (IMD) attributed the deterioration to a fresh Western Disturbance affecting the northwest region. While winds picked up slightly, it wasn’t enough to result in any major improvement in air quality.
“A Western Disturbance (WD) is impacting the Western Himalayan Region, which is impacting the northern plains as well. Although this WD is feeble and the impact will wane away soon, whenever there is a WD approaching , the winds slow down and humidity levels rise because of partly cloudy skies,” said a senior IMD scientist.
“Winds dying down and high moisture in the atmosphere allow accumulation of pollutants while there is no dispersion as such, which results in high pollution levels.”
Temperatures are likely to remain high over the next few days because of WD and moisture-laden easterly winds blowing over the city. Air quality is likely to remain so over the next two days.
It is likely to improve significantly with another WD likely to affect the region during January 5-7, which is expected to be strong and may result in showers.
“An intense Western Disturbance is likely to affect the Western Himalayan Region during January 4-7, with possibility of isolated heavy rainfall over plains of northwest India, including parts of Delhi around January 5-7, which may clean up the atmosphere of hing up pollutants” the official said.
Delhi saw the longest bad air spell in December with six consecutive ‘severe’ air quality days and a fortnight of ‘very poor’ days.
The air quality had improved briefly on account of good winds, but again returned to ‘very poor’.