AQI of Delhi plunged to severe category on November 1st. The first five days of November witnessed severe Air quality index for 3 days and very poor AQI for two days. On November 1st AQI was 424, it dropped to 376 on November 2nd, becoming severe on 3rd and 4th. It further dropped again to 381 in very poor category.
Last year, we saw farm fires peaking between November 3rd and 10. Therefore we can say we are in the peak period of stubble burning. But there is a silver lining winds have changed direction from north-westerly to easterly and south-easterly. Haryana and Punjab or in northwest of Delhi the smoke of stubble from Punjab and Haryana has reduced due to change in wind direction.
A Western Disturbance is travelling across Western Himalayas and has induced a cyclonic circulation over Pakistan and Punjab. Easterly winds will continue for at least next 2-3 days. Therefore, the contribution of smoke from farm fire will remain on lower side. Winds will change its direction once again from November 9th leading to further increase in pollution.
Two weather factors are crucial for reducing air pollution. First is widespread rainfall which help in washing down the pollutants. Another is is moderate to strong winds which usually disperse the pollutants. But unfortunately, we do not foresee any of these weather activities during next one week or so.
