Adverse meteorological conditions could lead to spike in air pollution, says CPCB
Last year, in September and October, there were seven rainy days that brought around 121mm rain compared to only three rainy days this year in the same period that brought only 21mm rainUpdated: Oct 16, 2020, 16:53 IST
The meteorological conditions for the dispersal of pollutants are more adverse this year compared to last year, Central Pollution Control Board (CPCB) officials said at a technical briefing on air pollution on Friday, suggesting that pollution levels could be relatively higher this year.
Last year, in September and October, there were seven rainy days that brought around 121mm rain compared to only three rainy days this year in the same period that brought only 21mm rain. The average ventilation index in the same period this year is 1,389 m2/s but the minimum recorded was only 636 m2/s. A ventilation index of more than 6,000 m2/s is considered favourable for the dispersion of pollutants, according to CPCB officials.
Prashant Gargava, member secretary, CPCB, said harvest of the kharif crop and stubble burning has started earlier than normal this year. He added so the peak of stubble fires may not coincide with the most adverse meteorological conditions this year.
Last year, the contribution from stubble fires to Delhi’s air pollution peaked on October 31 when it was 44%. Diwali was celebrated on October 27 last year.
“This year, because stubble fires have started relatively early, we are hoping that the peak contribution from fires reduces by the time minimum temperature start falling significantly and before Diwali,” said Gargava.
Diwali will be celebrated on November 14 this year.
Another development, which could mean lower contribution from stubble fires this year, is that area under non-Basmati paddy (which leaves stubble that needs to be disposed of) has reduced in both Haryana and Punjab this year. In Punjab, the area under non-Basmati paddy has reduced from 22.91 lakh ha to 20.76 lakh ha this year. In Haryana, the area has reduced from 6.48 lakh ha to only 4.27 lakh ha.
“I have been informed that farmland of over 1 lakh ha has switched over from paddy this year which is a very important development,” added Shiv Das Meena, chairman, CPCB.