Delhi is the world's most polluted major city, according to an air quality index, or AQI, measured by Switzerland's IQAir. Pakistan's Lahore comes next.
The World AQI website shows India in the second spot after Qatar as having the most polluted cities. This index also includes Delhi.
Delhi Chief Minister Arvind Kejriwal, however, tweeted that Delhi is not in the list of 10 most polluted cities in Asia, which includes eight from India.
SAFAR data shows the share of stubble-burning in Delhi is 2-3 per cent, less than 15 per cent recorded last year at this time. But the data also shows fire counts are gradually increasing and are at par with the fire count last year this time (over 1,500). SAFAR is short for System of Air Quality and Weather Forecasting and Research.
The pollutant PM2.5 level currently is almost 400 micrograms per cubic metre close to Greater Kailash in south Delhi. That's 80 times the World Health Organisation's safe limit of 5 micrograms (annual average).
Delhi's air quality inched closer to the "very poor" category this morning as unfavourable meteorological conditions allowed accumulation of pollutants while emissions from firecrackers and crop residue-burning compounded the situation, news agency Press Trust of India reported.
Delhi's AQI stood at 298 at 6 am today. An AQI between zero 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".
Yesterday, the national capital reported a 24-hour average AQI of 259, the lowest for the day before Diwali in seven years.
But pollution levels increased overnight after temperature and wind speed dropped and people burst firecrackers in several parts of Delhi.
The number of farm fires rose to 1,318, the highest this season so far, PTI reported.
Delhi has banned the production, storage, sale and bursting of firecrackers this Diwali. Those caught violating the ban would be fined and jailed for six months.
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