For a second year, New Delhi's chief minister has likened the city to a "gas chamber". In October and November, there are 20-25 days when the pollution level increases in Delhi because of stubble burning (in neighbouring states).
Experts have predicted that the air quality will continue to oscillate between the "very poor" and "hazardous" category till next week because of not so favourable weather conditions. Although still in the severe category, it has declined to the lower ranges.
According to System of Air Quality and Weather Forecasting And Research (SAFAR), the overall air quality index (AQI) in Delhi was recorded at 385 till 8 am, which fall in the "very poor" category.
An AQI between 0 and 50 is considered "good", 51 and 100 "satisfactory", 101 and 200 "moderate", 201 and 300 "poor", 301 and 400 "very poor", and 401 and 500 "severe". Faridabad and Ghaziabad also recorded "severe" air quality, data showed.
On Sunday, Delhiites breathed the cleanest air in three weeks, according to CPCB data.
A Delhi government official blamed the pollution for lighter-than-usual traffic on already holiday-thinned streets, while a Delhi airport official said some domestic and global flights were delayed for up to two hours due to poor visibility. The index was 5000 sqm/second on Tuesday, the IITM had said. Monday's air quality was just as bad, with the AQI at 448.
An official of the Centre-run System of Air Quality Forecasting and Research (SAFAR) said intensified stubble burning is contributing almost 24 per cent of the air pollution in Delhi. The air quality remained "severe" Monday and Tuesday before moving to the "very poor" category Wednesday morning.
The city is facing its highest pollution level since Diwali.
A damning report by the World Health Organization this year said India was home to the world's 14 most polluted cities, with Delhi the sixth worst.
The Odd-even rule in Delhi is part of the Graded Response Action Plan (GRAP), which measures the air pollution levels.
Local factors such as emission from vehicles, garbage burning, polluting industries, and construction activities are responsible for deteriorating air quality. "This is a temporary phase, largely because of meteorological conditions over Delhi and the surrounding areas".
All stone crushers and hot mix plants generating dust pollution have also been closed. The odd-even auto scheme, much like last time, will aim to reduce the vehicle footprint on roads in a bid to curb air pollution.
CPCB chairperson S P S Parihar said the reason the ban is imposed till December 26 is because winds are expected to pick up and the pollution could go down then.