Delhi's AQI poor, share of farm fires still low
The city's air quality deteriorated slightly over a 24-hour period to touch a reading of 241 as per the Central Pollution Control Board’s (CPCB) daily 4pm national bulletin.
Delhi’s air quality remained in the “poor” category for the third consecutive day on Tuesday, deteriorating slightly over a 24-hour period to touch a reading of 241 as per the Central Pollution Control Board’s (CPCB) daily 4pm national bulletin. The air quality index (AQI) reading for Monday was 237, and for Tuesday it was 232.
Forecasts by the Early Warning System (EWS), utilised by the Commission for Air Quality Management (CAQM) in NCR to take pre-emptive action, show Delhi’s AQI is likely to remain in the “poor” category for the next few days.
An AQI between 0 and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very poor”, and 401 and 500 “severe”.
According to data by the Consortium for Research on Agroecosystem Monitoring and Modelling from Space (CREAMS), which comes under the Indian Agricultural Research Institute (IARI), Nasa satellites over a 24-hour period starting Monday, recorded a total of 506 farm fires in Punjab, Haryana and Uttar Pradesh. In comparison, there were 496 farm fires over the previous 24-hour period, the data showed.
This also kept the contribution of stubble burning to Delhi’s PM 2.5 concentration at around 3% — the same as October 17, the System of Air Quality and Weather Forecasting And Research (Safar), a body under the ministry of earth sciences, said. The body has been calculating the contribution of stubble burning to Delhi’s PM 2.5 concentration each winter, and found that it reached a high of 48% on November 7 last year.
Gufran Beig, founder-project director at Safar, said the contribution of farm fires to Delhi pollution was negligible at present, but with the overall farm fire count rising, it could spike in the coming days. “The long-range transport wind speed is not that high and so not much contribution is reaching Delhi. Based on the increase in numbers, the contribution will also increase in the coming days,” he said.
VK Soni, scientist at India Meteorological Department (IMD) and part of the CAQM subcommittee which implements the Graded Response Action Plan (Grap), said forecasts currently show that “poor” air days are expected in Delhi until October 21.
“Action under Grap and stage II measures can be imposed if forecasts show ‘very poor’ air is expected; however, so far, it is likely to stay in ‘poor’ for the next three days. We will continue to review the air quality each day and a meeting can be called if it is expected to be ‘very poor’,” he said.
Delhi recorded a maximum temperature of 33.1 degrees Celsius on Tuesday – one degree above normal for this time of the year. The minimum was meanwhile recorded at 17.5°C — 1°C below normal. According to IMD, no rain is expected in the region until at least October 24, with Delhi expected to have a maximum and minimum of 32°C and 18°C respectively on Wednesday.