Pollution of Delhi and NCR was in very poor category until November 8. It deteriorated further and now is in severe category over many parts of Delhi. Places like Dhirpur, Delhi University and Noida witnessed air quality index above 450.
Winds over Delhi at lower levels are from east and southeast direction but upper-level winds at around 5,000 feet are blowing from northwest. These winds are carrying smoke of stubble burning from Punjab and Haryana as well as parts of Central Pakistan. These winds have subsided over Delhi and NCR leading to increased contribution of smoke from stubble burning. Today the contribution of smoke is around 30% over Delhi.
Light winds during daytime and almost calm wind during night did not allow the pollutants to disperse. Moreover, mist and haze develops during morning hours. The pollutants get deposited over water vapor available in mist and haze. In the absence of moderate winds, these pollutants keep lingering in lower atmosphere near Earth's surface.
We do not expect any significant increase in wind speed in coming days. Another factor which is essential to wash away the pollutants is moderate to heavy rain. We do not expect any significant rainfall for at least next 4 to 5 days. Therefore, chances of relief from ongoing air pollution is ruled out.