Pollution spikes slightly with as wind changes, likely to worsen

Noida: The air quality of Noida and adjoining regions have started going downward with north-westerly and westerly winds bringing dust laden air and smoke from neighbouring

Noida: The air quality of Noida and adjoining regions have started going downward with north-westerly and westerly winds bringing dust laden air and smoke from neighbouring states of Haryana and Punjab, where a few farmers have begun harvesting and burning the crop residue.

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The air quality, however, is not yet drastic as the stubble burning is sporadic, and also thanks to high wind speeds and good ventilation.

On Monday, the air quality index (AQI) — as recorded by the Central Pollution Control Board, on a scale of 0 to 500 with 0 being the least polluted and 500 the most severe — was 144 for Noida, 162 for Ghaziabad and 171 for Greater Noida, all in the moderate category.

The AQI, a week ago, was 48 (good) for Noida, and 59 (satisfactory) for Ghaziabad and 58 (satisfactory) for Greater Noida.

An official at the India Meteorological Department (IMD) said the winds have changed from the clean and moist easterly and south-easterly (during the monsoon) to the drier westerly and north-westerly.

The westerly and north-westerly winds are dry and cold in nature, and flow towards Delhi and NCR during the post monsoon time. The winds are major carriers of pollutants from Punjab and Haryana where crop stubble is burned to prepare the fields for the sowing of rabi crops (winter crops).

“The worsening of air quality has started, even though it is still in the upper range of moderate levels for now. It’s a mixed effect of meteorological reasons and stubble burning in Haryana and Punjab. As the festival season is set to increase the traffic congestion, and since by October mid stubble burning may also increase, the air quality is likely to worsen further,” Shambahvi Shukla, senior research associate, Centre for Science and Environment (CSE), said.

The IMD has said there is hardly any chance of rain in the region, which, according to the weather analysts, takes away one natural way of settling pollutants, majorly the particulate matter (PM)2.5 and 10.

“We are seeing favourable conditions for monsoon withdrawal from north-west India within the next three days. There are hardly any chance of rain and the westerly and north-westerly winds are set to become predominant,” IMD chief M Mohapatra said.

According to the System of Air Quality and Weather Forecasting And Research (SAFAR), Ministry of Earth Sciences, the late withdrawal of monsoon is not a good sign for the air quality in northern India as the calmer surface winds and stagnant weather conditions during the monsoon withdrawal are favourable for rapid formation of fine particles and accumulation of pollutants.

Any addition of internal pollutants — like those from fire crackers — and external sources like stubble burning will make the air quality worse.

“Last year, the monsoon withdrawal from Delhi happened around October 5 and by the second week of October, it had withdrawn from the entire country. This year, the monsoon withdrawal from Delhi is expected to be around October 15, which is late and not a good sign for the air quality,” Gufran Beig, project director, SAFAR, said.

The monsoon withdrawal from Delhi was late in 2016 and 2017. “If stubble burning is more and local pollutants, especially from fireworks and vehicles are high, it will have a direct impact on the air quality of Delhi-NCR,” Beig warned.

Meanwhile, some of the farmers in Punjab and Haryana have started the stubble burning, claiming they have received no support from the government for stubble management as promised.

“Farmers need at least ₹6,000 per acre to afford the machinery to manage the stubble, and we don’t have that kind of money. In such a scenario, farmers have no option but to burn the stubble. Only a few farmers have started harvesting and some have started burning the stubble already. In Haryana, there are more incidents of crop residue burning,” Omkar Singh, a farmer and member of Bharatiya Kisan Union in Punjab, said.