Change of wind direction to bring respite from stubble burning smoke

: After five days of poor air, pollution in the national capital is likely to drop marginally Monday onwards, buoyed primarily by a shift in the wind direction,

: After five days of poor air, pollution in the national capital is likely to drop marginally Monday onwards, buoyed primarily by a shift in the wind direction, according to a Sunday forecast by the Union ministry of earth sciences.

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The ministry’s air quality early warning system forecast said Delhi’s air quality will improve and enter the ‘moderate’ category on Monday, where it is expected to remain till Tuesday at least, the forecast read.

“The predominant surface wind is likely to be coming from Delhi’s east, with wind speeds up to 12kmph and mainly clear skies on Monday,” the early warning system said. On Tuesday, winds are expected to travel into the Capital from the southeast, while their speed will likely remain similar and skies may stay mainly clear, according to the system.

The change in wind direction means the impact of crop residue burning in Punjab and Haryana on Delhi’s air will be minimal on Monday and Tuesday.

With the onset of the winters, the national capital, over the last two weeks, received winds from the north-west that carried plumes of stubble burning smoke from the rural pockets of the two neighbouring states.

On Sunday, Delhi’s average air quality index (AQI) reading, as per the Central Pollution Control Board (CPCB) was 216, marginally better than Saturday’s 221. On Sunday, Delhi received north-westerly winds, blowing at a speed of 15kmph.

The Union earth science ministry’s System of Air Quality and Weather Forecasting and Research (Safar), also predicted that a shift in Delhi’s surface wind direction will help improve the quality of air “marginally”.

Safar data shows that on Saturday alone, 448 cases of farm fires were spotted over Punjab and Haryana through satellite monitoring. These cases have been increased regularly since September 12, when farmers started harvesting the early varieties of paddy and started setting their fields on fire to get rid of the stubble remains.

“We are sharing these forecasts with the CPCB. Medical experts suggest air pollution may add to peoples’ miseries during the Covid-19 pandemic. With the government’s graded action plan [Graded Response Action Plan, also known as Grap], we hope to keep the level of air pollution very low this year,” said Madhavan Rajeevan, secretary, Union ministry of earth sciences.

For the last five days, Delhi’s air has been in the ‘poor’ zone, dropping into the category with an AQI of 215 on Wednesday, after a long spell in the ‘moderate’ zone.

The Delhi government blamed this spike in pollution on the increasing instances of stubble burning in Punjab and Haryana.