Noida, Ghaziabad, Greater Noida top three polluted cities in country
Noida, Ghaziabad and Greater Noida made it to the pinnacle of the country-wide pollution charts on Saturday, as per air quality index (AQI) figures of the Central Pollution Control Board (CPCB).
Greater Noida ended up with the worst air quality in the country, followed by Noida and Ghaziabad.
Oddly, this is despite a slight improve in air quality index (AQI) figures on Saturday from the day before, brought about by marginal increase in wind speed leading to better ventilation, according to data from CPCB.
On Friday, Noida was the most polluted city in the country, while Ghaziabad was a close second.
“The wind speed on Saturday was around 8 kilometre per hour (kmph) at its peak towards the afternoon, against 5 kmph on Friday. Weather conditions will improve further by Sunday and Monday, with winds speeds changing, leading to rise in mercury and improvement in ventilation,” said Kuldeep Srivastava, head, regional weather forecasting centre, India Meteorological Department (IMD).
He added that due to very dense fog in the morning hours in the National Capital region (NCR), the wind speed, though slight faster on Saturday afternoon, was unable to disperse pollutants. The foggy conditions and heavy air, due to low temperatures, tend to trap particle pollutants, making it difficult for moderate or light winds to disperse them.
According to CPCB, the AQI of Noida, on a scale of 0 to 500, on Saturday was 434 against Friday’s 475. The AQI of Greater Noida was 438 – highest in the country – against 464 a day earlier. The AQI of Ghaziabad was 423, against 458 a day earlier.
An AQI between 101 and 200 is considered “moderate”, between 201 and 300 is “poor”, between 301 and 400 is considered “very-poor” and above 400 is considered “severe”.
Levels of the major pollutant particulate matter (PM) 2.5 in the region saw a slight improvement.
The average PM2.5 for Noida on Saturday was 351.22 microgrammes per cubic metres (µg/m3), against 425.37µg/m3 on Friday. The average PM2.5 for Greater Noida was 341.64µg/m3 against 402.37µg/m3 a day earlier. The PM2.5 level for Ghaziabad was 404.06µg/m3 against 427.67µg/m3 a day earlier. The safe limit for PM2.5 is 60µg/m3.
According to the System of air quality and weather forecasting and research (Safar), AQI is likely to improve to the upper end of “very poor” levels.
“Slight improvements in surface winds are observed; wind speed is moderate and west, north-westerly. Due to slightly better ventilation, marginal improvement in air quality is forecasted for Sunday, and the AQI likely to improve to the higher end of “very poor” category. The Safar forecast reveals that AQI will continue at the high end of the “very poor” category for January 18 (Monday). This is likely to be the first extended extreme air pollution event for 2021. Further improvement is expected on January 19 and 20,” said Safar on Saturday.