An air pollution forecast issued by the scientists at the System of Air Quality and Weather Forecasting and Research (SAFAR) for October and November this year says that Delhi might see no ‘severe’ air quality days in October and November if the stubble burning season peaks by October-end or stubble burning is reduced with fire counts being half of what they were last year.
This is based on the premise of a normal retreat of the southwest monsoon. The India Meteorological Department (IMD) declared on September 29 that the monsoon has withdrawn from Delhi and Punjab. The ‘normal’ withdrawal date for Delhi is September 25, while the normal withdrawal from Jalandhar, Punjab, is September 21. The monsoon withdrawal was delayed last year exiting Delhi and Punjab on October 8.
If stubble burning is “business-as-usual” and there are approximately 80,000 fire counts till November 30 then Delhi could see six to eight ‘severe’ air quality days in October and November, according to the forecast. Most of these ‘severe’ air days are likely to be in November, said Gufran Beig, founder project director, SAFAR.
“On average, for October and November, the effective fire count for the last two years was 78,000 to 80,000. Last year, it was around 80,000,” Beig said.
If fire counts are reduced by half with regard to 2021 then there could be ten ‘good’ or ‘satisfactory’ air days in October and November. This number could fall to five such days if the stubble burning is on the same scale as last year, according to the forecast.
According to the outlook for the next two months, the anti-cyclonic circulation that sets in marking the end of the monsoon could make the atmosphere stable a little earlier, resulting in “mild deterioration” of AQI earlier than last year, that is, from October 10.
With the monsoon retreat being normal, Delhi is likely to avoid extreme pollution events till October-end.
An earlier Diwali compared to last year, when it is not as cold, could lead to lesser accumulation of pollutants, the forecast indicates. The day after Diwali (November 5) saw a sharp spike in pollution levels last year.
“If Diwali and peak stubble burning season do not coincide back-to-back ‘severe’ air quality days like what we saw last year, we won’t be there,” Beig added.
On Friday, the Air Quality Index (AQI) was 173 in the ‘moderate’ category.