Slight slip in air quality on Diwali’s eve

Noida:

Noida:

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The air quality of Noida and Greater Noida settled in the ‘very poor’ category on the eve of Diwali as the weather conditions changed with the winds now carrying smoke from neighbouring states.

On Friday morning, the wind direction changed from easterly to north-westerly, with smoke coming from neighbouring Punjab and Haryana, leading a hike in the share of PM2.5 levels and deteriorating the air quality.

According to weather analysts, the air quality could slip further on Diwali, as the wind speed is likely to fall further but the direction will remain the same -- north-westerly.

“The wind direction changed from easterly to north-westerly around 9.30am in the region in Friday due to which the ventilation of the pollutants stopped. The NW winds came at a speed of maximum 8 kmph. On Diwali, the wind speed will drop to 5 kmph, due to which the pollution could rise further,” said Kuldeep Srivastava, head, regional weather forecasting centre, India Meteorological Department (IMD).

Srivastava said due to a approaching western disturbance, the day after Diwali may see light to moderate rainfall after which the wind speed will catch-up to 15 kmph, leading to better ventilation of the pollutants.

According to the system of air quality and weather forecasting and research (SAFAR), the current wind directions are not good for the region.

“The stubble burning-induced impact in AQI is expected to increase from negligible to moderate for the next two days. Although the level of PM2.5 is predicted to be at the edge of very poor to severe, it is expected to be much better as compared to the past four years around the Diwali period with 0% firecracker emission scenario. The biomass plume transport-level winds have become north-westerly by early Nov 13 and forecast to continue until November 14, which is not good and predicted to have high potential to transport biomass plume in the next 2 days to Delhi and surrounding regions,” said the SAFAR repot on Friday.

Meanwhile, the air quality index (AQI) of Noida, on a scale of 0 to 500, was 337 against 305 a day earlier. The AQI of Greater Noida was 336 against 327 a day earlier, while the AQI for Ghaziabad was 382 against 328 a day earlier.

The average PM2.5 for Noida increased to 206.62 microgrammes per cubic metres from 180.62 microgrammes per cubic metres a day earlier. The PM10 for Noida dropped to 308.89 against 342.17 units a day earlier.

For Greater Noida, the PM2.5 was 186.85 units against 180.63 units a day earlier. The PM10 for Greater Noida was recorded at 416.51 units against 385.57 units a day earlier.

“Combustion is a major source for PM2.5, while dust is for PM10,” said Shambhavi Shukla, program officer, air pollution, Centre for Science and Environment (CSE).