Delhites on Monday woke to the predictable grey sky but it was marginally less grey than it was on Sunday. There was hope that the worst might be over, as the air quality index (AQI) improving to 389 in the morning, down from the figures close to 1,000 on Sunday.

Still, Delhi continues to have the worst air pollution for any city in the world, and an AQI of 389 continues to place it in the ‘hazardous’ category.

On Monday, the Delhi government started the ‘odd-even scheme’, barring half the private vehicles from roads with a view to control vehicular pollution. This is the third time in five years that the Arvind Kejriwal government has resorted to this measure.

After a doomsday-like sky on Sunday, the union government too decided to intervene, and the prime minister’s office (PMO) has started monitoring the air situation.

The air pollution and public health crisis are blamed primarily on the burning of crop residue in neighbouring Haryana and Punjab, along with other factors like Diwali fire crackers, large numbers of vehicles and construction activities.

Sunday’s spike was also due to mild showers of Saturday which only trapped the pollutants rather than clearing them away. In the days to come, apart from the vehicular pollution getting limited, the farm burning is also expected to come down. Moreover, the Met department has forecast rains later this week which can be expected to clear the air.

In recent years, toxic air quality of the national capital has been hitting headlines during winters. However, no effective precautions are taken in the absence of coordination among the state governments and the centre.