Delhi: Air quality very poor after briefly touching severe category on Thursday

Wind speeds in the Capital were expected to touch around five to six km per hour during the day and air quality was likely to remain in the very poor category

Delhi’s air quality improved to the very poor category on Friday morning after briefly touching the severe zone on Thursday even as no improvement was expected over the weekend with forecasts showing no significant change in meteorological conditions. Wind speeds were expected to touch around five to six km per hour during the day and air quality was likely to remain very poor.

A 24-hour average Air Quality Index (AQI) of 378 (very poor) was recorded at noon on Friday. (HT PHOTO)

A 24-hour average Air Quality Index (AQI) of 378 (very poor) was recorded at noon on Friday. An AQI of 398 (very poor) was recorded at 4pm on Thursday before the air quality worsened to 401 (severe) at 7pm.

The minimum temperature of 13.3°C on Friday was three degrees above normal. It was 12.6°C on Thursday. The wind direction was likely to remain easterly on Friday before changing to northwesterly on Saturday. The minimum temperature was expected to drop to 11°C by Sunday. The maximum will hover around 25°C until Sunday.

There were nine severe air days in Delhi in November when the AQI was over 400. It also recorded another nine days when the AQI was on the brink of severe—an AQI between 390 and 400. The Capital recorded 18 days of near severe or severe air days in November, the highest number of such days since 13 of them were recorded in November 2021 and 11 in November 2016.

The Commission for Air Quality Management (CAQM) on Thursday said there was a relatively low average wind speed of four km per hour in Delhi in November. There were long spells where the winds were calm. An average wind speed of 10 km per hour is effective in the dispersion of pollutants.

CAQM said paddy farm fires in Punjab and Haryana in November were much lower than in the last three years. It said highly unfavourable climatic and meteorological conditions contributed significantly to the PM2.5 load in Delhi. “The peak of the paddy harvesting activity in Punjab and Haryana coincided with the festival of Deepawali this year, further aggravating the air pollution...”

It said Punjab recorded 36,663 farm fires until November 30, down from 49,922 last year. Haryana reported 2,303 fires this year, down from 3,661 last year.

Delhi’s 24-hour average AQI was 373 in November. It was 321 last November and 376 in November 2021. CAQM said if the entire year’s average AQI was looked at, the year was cleaner than previous years.