In Delhi, air still in severe category for 4th straight day
The air quality index (AQI) in the national capital on Sunday morning remained in the severe category for the fourth consecutive day, despite a marginal improvement.
The Central Pollution Control Board (CPCB) data showed that the AQI was 405 at 7 am on Sunday.
An AQI between 401 and 500 is considered to be severe, which causes distress and respiratory complications, especially for children and senior citizens.
On Thursday, Friday and Saturday, Delhi’s average 24-hour AQI stood at 450, 406 and 427, respectively.
Scientists have predicted that the relief from bad air is unlikely till Tuesday (November 10).
Over 4,500 farm fires that are raging in neighbouring Haryana and Punjab contributed to around 32% of ultrafine particulate matter (PM 2.5), which could not be dispersed, in Delhi’s air despite slightly better wind speed on Saturday, as compared to Friday.
VK Soni, the head of India Meteorological Department (IMD) environment monitoring research centre, said that during the day the average wind speed was around 12 kilometres per hour (kmph), which was higher than that on Friday.
However, its impact was not seen on the AQI because of an increase in stubble burning cases in Haryana and Punjab. He said that the north-westerly winds are bringing a heavy load of pollutants from these farm fires to the national capital.
“For the last three days we have been observing that the number of farm fires spotted over Punjab alone is over 4,000. Usually, these fires go up on Sundays at this time of the year. Though the wind speed picked up during the day, the improvement in air quality was not all that significant only because of an uptick in farm fire cases,” Soni said.
Kuldeep Srivastava, the head of IMD’s regional weather forecasting centre, said that in parts of central Delhi the wind speed fluctuated between six and eight kmph on Saturday, but the corresponding figure was up to 16 kmph in outer parts of the national capital.
“The wind is blowing from the north-western direction, which is bringing a large share of smoke from Haryana and Punjab,” he said.
Srivastava said that there is a forecast of the wind direction changing to easterlies from Tuesday, but before that it will reduce drastically, possibly pushing the city’s air quality further into the “severe” zone.
“During the transitional stage of a change in wind direction, the speed reduces drastically. The wind may become calm from Sunday evening. This will only lead to a further worsening of air quality,” he warned.
IMD had predicted a foggy Sunday morning in the national capital. The maximum and minimum temperature is expected to be around 30 degrees and 11 degrees Celsius (C), respectively.
On Saturday, Delhi’s minimum temperature, recorded at the Safdarjung observatory, was 11.8 degrees C – two degrees below normal. The maximum temperature was 30 degrees C – one degree above normal.