Noida’s air quality drops to ‘poor’ again

Noida: After being in ‘moderate’ category for a day, Noida’s air quality slipped to ‘poor’ on Tuesday as the weather conditions became unfavourable for the ventilation.

Noida: After being in ‘moderate’ category for a day, Noida’s air quality slipped to ‘poor’ on Tuesday as the weather conditions became unfavourable for the ventilation. The air quality of Greater Noida and Ghaziabad also dropped, but stayed within the ‘poor’ levels.

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On Monday, Noida had reported its best air quality (‘moderate’) since November 17.

According to the Central Pollution Control Board (CPCB), the air quality index (AQI) of Noida on Tuesday was 243 against 176 a day earlier. Greater Noida’s air quality was 290 against 256 a day earlier, both ‘poor’.

Ghaziabad’s AQI also worsened from lower level of poor category towards the upper level. On Tuesday, the AQI of Ghaziabad was 282 against 243 a day earlier.

AQI between 101 to 200 is considered ‘moderate’, between 201 and 300 is ‘poor’, between 301 and 400 is ‘very-poor’ and above 400 is considered ‘severe’.

According to the weather analysts, while the excessive winter conditions make the air heavy and trap the pollutants, the stronger winds would still help with ventilation and if the local emissions spike, the drop in air quality will only be marginal.

“The wind speed on Tuesday was 12km per hour while the temperature also dipped leading to cold waves. On Monday, the wind speed was over 15kmph. The winds will prevail for next few days and thus despite resistance due to the low temperatures, the ventilation will be there. So the air quality will be okay and if it worsens, it will be a marginal drop,” said Kuldeep Srivastava, head, regional weather forecasting centre, IMD.

The fine particles or PM2.5 levels also spiked and are currently two-time the standards.

On Tuesday, PM2.5 for the past 24 hours in Noida was recorded at 106.64 microgrammes per cubic metres (µg/m³) against 99.24 µg/m³ a day earlier. The PM2.5 level for Greater Noida was 131.50 µg/m³ against 119.19 µg/m³ a day earlier.

The PM2.5 levels for Ghaziabad on Tuesday also increased to 129.99 µg/m³ against 112.49 µg/m³ on Monday. The safe limit for PM2.5 is 60 µg/m³.

According to the System of Air Quality and Weather Forecasting and Research (SAFAR), AQI is likely to improve over next few days due to stronger winds. “Though the maximum and minimum temperatures are likely to fall, better ventilation conditions are forecasted for the next 72 hours, due to high wind speed and deepen nocturnal boundary layer height. AQI is likely to marginally deteriorate today from the moderate to the poor category, and likely to improve on 16th and 17th Dec to the poor to moderate category,” said a SAFAR statement on Tuesday.