New Delhi, Nov 10 : Overnight rain led to a rapid improvement in Delhi's air quality on Friday morning and cleared the haze that had been lingering for over 10 days.
Delhi's AQI stood at 376 at 9 am, rapidly improving from 408 at 7 am on Friday and 460 at 11 pm on Thursday. The air quality is expected to improve further due to wind speed favourable for the dispersion of pollutants.
The air quality index (AQI) at any given time is the average of readings taken in the last 24 hours.
The Safdarjung Observatory, Delhi's primary weather station, recorded 6 mm of rainfall in 24 hours ending 8.30 am on Friday, the IMD said. The Met department data showed most of the areas in Delhi recorded light rain.
Light to moderate rain also occurred in Noida, Gurugram and other adjoining areas.
The India Meteorological Department (IMD) had earlier predicted a marginal improvement in air quality just ahead of Diwali owing to favourable meteorological conditions, including light rain.
IMD officials had also said a change in the wind direction from northwest to southeast due to a fresh western disturbance affecting northwest India would help reduce the contribution of smoke from stubble-burning.
Once the western disturbance passes, the wind speed will increase from around five to six kilometres per hour at present to around 15 kilometres per hour on November 11, which will help disperse pollutants ahead of Diwali (November 12), an IMD official said.
Last year, a decrease in stubble-burning incidents, delayed spells of rain, an early Diwali, and favourable meteorological conditions prevented the capital from turning into a gas chamber following the festival.
According to data from the Decision Support System, a numerical model-based framework capable of identifying the sources of particulate matter pollution in Delhi, stubble-burning in the neighbouring states, particularly Punjab and Haryana, accounted for 38 per cent of the air pollution in Delhi on Wednesday. It was 33 per cent on Thursday and is likely to be 16 per cent on Friday.
The data also show that transport is another major factor, contributing 12 to 14 per cent to Delhi's foul air.
In view of the worsening air pollution, the city government is planning to induce artificial rain on November 20-21 through cloud seeding.
A proposal in this regard will be submitted to the Supreme Court, which is hearing a clutch of petitions on the air pollution issue, on Friday.
The government on Wednesday rescheduled the December winter break of all schools. The winter break in the schools will now be from November 9 to November 18.
Delhi Environment Minister Gopal Rai said the entry of app-based taxis into the national capital had been banned in accordance with the Supreme Court's orders.
He also said the odd-even car-rationing scheme would be implemented in the city after the top court reviewed its effectiveness and issued an order. The matter will be heard on Friday.
