After many days, clear skies and breather from pollution in Delhi
The day’s average AQI dropped from 378 on Tuesday to 282 on Wednesday. It had shot up to 390 on a scale of 0 – 500 on Monday.delhi Updated: Dec 06, 2017 22:39 IST
Delhi’s air quality improved remarkably on Wednesday. The Air Quality Index, which was hovering in the ‘very poor’ category, came down to poor category after a gap of almost two weeks.
The day’s average AQI dropped from 378 on Tuesday to 282 on Wednesday. It had shot up to 390 on a scale of 0 – 500 on Monday.
The last time that the AQI had dropped to ‘poor’ levels was on November 24. It was 288, a few notches above Wednesday’s 282. The last time the AQI had dropped below 282 was on October 12. It was 268.
“The concentrations of particulate matter in the air, which had nearly touched severe levels on Monday, also plunged. The levels of both PM10 and PM2.5 have almost halved over the past 48 hours,” said D Saha, head of the air quality laboratory at the Central Pollution Control Laboratory.
Even though in December 2015, Delhi witnessed around 11 days when air quality was in poor category, in December 2016 the National Capital got just 3 days of poor category of air pollution.
Experts attributed this improvement to the sudden change in the weather. The wind speed picked up, the sky cleared up and the humidity level dropped. These factors helped to flush out the pollutants which had accumulating over the past few days.
“The wind speed which had dropped below 2 m/s, picked up to around 5 m/s on Wednesday. Strong winds from the northwest helped to disperse the pollutants. An almost clear sky ensured that sun’s rays heat up the atmosphere which increased the mixing height. This further helped to clear the pollutants,” said Saha.
The local met department is expecting some rain around the middle of next week as a western disturbance is likely to hit Delhi-NCR. This is likely to further improve the air quality.
“A Western Disturbance is approaching and is likely to trigger some rain in Delhi-NCR on December 12. We are also expecting rain in almost all the states of northwest India,” said Kuldeep Srivastava, scientist with the regional weather forecasting centre.
Experts said that if there is rain in entire northwest India then air quality could improve further as the pollutants would be washed away.
The state environment department has urged the departments and agencies concerned to sprinkle water on city’s roads and continue their actions against polluting vehicles.
First Published: Dec 06, 2017 22:39 IST