Winds from east pave way for cleaner Diwali this yearUpdated: Oct 25, 2019, 21:29 IST
Noida: With easterly winds sweeping across the region, the air has started showing signs of improvement with the air quality of Noida and Greater Noida now climbing back to ‘poor’ category, while Ghaziabad remained in the lower level of ‘very poor’ category.
Favourable meteorological conditions are likely to continue till Diwali (October 27), weather analysts said, giving hopes for a cleaner Diwali this year, in comparison to last two years.
Weather analysts attributed Thursday’s sudden spike in pollution levels in Delhi-NCR to the slower pace of winds due to which the north-westerly winds, carrying along smoke from neighbouring Punjab and Haryana, got accumulated and trapped. Slower winds are common during the transitional period when the wind changes directions from north-westerly to easterly.
However, the easterly and north-easterly winds which started entering the Delhi-NCR from Thursday afternoon at a speed lesser than 3kmph, started picking up pace on Friday going up to 15kmph, thereby increasing the ventilation effect and dispersing pollutants.
“The lower or surface winds are now easterly and are blowing at a higher speed, thereby dispersing pollutants. That is the reason why the pollution levels are now dropping. The easterly winds are expected to continue for another two days at a pace of around 8 to 9 knots, and they will change back to north-westerly on Monday, October 28. So we can predict that Diwali this year will not be as polluted as the past two years,” Mahesh Palawat, director private weather forecasting agency, Skymet, said.
The air quality index (AQI), as recorded by the Central Pollution Control Board (CPCB), of Noida on Friday, on a scale of 0 to 500, was 284 or ‘poor’ against 319 or ‘very poor’ a day earlier.
The use of conventional fireworks (despite a ban last year) and the traffic congestion due to the festival season led to a sharp rise in pollution, which became evident a day after the festival. Additional pollutants coming from the neighbouring states of Punjab and Haryana further worsened the air quality.
Since past two years, the region of Delhi-NCR has been receiving north-westerly winds bringing along with them the additional pollutants from stubble burning states.
“The air quality will also depend on the amount of fireworks burnt this time and proper imposition of additional measures under the graded response action plan (Grap). So even if the meteorological conditions are conducive for cleaner air, fireworks and local emissions still pose a threat,” Shambhavi Shukla, programme officer, clean air, Centre for Science and Environment (CSE), said.
Meanwhile, additional measures have been ordered by the Supreme Court-appointed Environment Pollution (prevention and control) Authority (Epca) to ensure a cleaner Diwali, which includes closure of coal-based industries till October 30 and banning the construction activities, stone crushers, etc between 6am and 6pm to control dust.