Delhi air severely polluted for sixth consecutive day

There is no likelihood of improvement immediately, scientists said

Delhi continued to record “severe” air quality for the sixth consecutive day. The city’s air quality index (AQI) reading on Tuesday morning was 487. On Monday, the city’s average AQI reading was 477. At 7am, the concentration of PM10 was 683 micrograms per cubic metres and PM2.5 concentration was 495 micrograms per cubic metres. Both PM10 and PM2.5 concentrations have been at least five times higher than the national safe standard since Monday. The city’s minimum temp was 10.7 degrees Celsius, 3 degrees below normal, and moderate fog visibility was 300 metres.

A combination of an extremely high number of stubble fires in Punjab, low to calm winds in the region and subsidence of air has led to Delhi recording “severe” air quality since November 5. (Amal KS/HT Photo)

Most cities and towns in the national capital region (NCR), such as Baghpat, Bhiwani, Bhiwadi, Bulandshahr, Ghaziabad, Gurugram and Noida recorded AQI readings in the higher end of the “severe” category on Tuesday morning.

There is no likelihood of improvement immediately, scientists said. “We are not expecting any significant improvement in air quality in the next few days. Wind direction is likely to shift from northwesterly to easterly today [Tuesday], but during such transition in wind direction winds are usually calm. There may be a marginal improvement in air quality on November 12 or 13,” said Kuldeep Shrivastava, head, regional weather forecasting centre.

A combination of an extremely high number of stubble fires in Punjab, low to calm winds in the region and subsidence of air has led to Delhi recording “severe” air quality since November 5.

“There is anti-cyclonic wind circulation in the lower levels and subsidence of air in large parts of northwest India presently. Both are linked to slow winds and accumulation of pollutants. We have been seeing a very large number of crop stubble fires. The combination of these factors is leading to the air quality index (AQI) reading hovering between ‘very poor’ and ‘severe’ categories for the past five days,” explained RK Jenamani, senior scientist, national weather forecasting centre.

There were over 5,000 stubble fires recorded in Punjab on Monday, according to the ministry of earth sciences. Harinder Singh Lakhowal, general secretary, Bharatiya Kisan Union, had said on Sunday that stubble fires will persist over Punjab for at least one more week until the harvesting of paddy is complete. “Fires will continue for a week or so. All the late varieties of paddy are being harvested now. Many parts of the state faced labour shortage this year. The farm labour belongs to Bihar and UP who had travelled back home during lockdown,” he had said.