The visibility in Delhi will remain poor for the next three days due to fog and smog, said Senior Scientist of the Indian Meteorological Department (IMD).
Meanwhile, not only Delhi but also two other metro cities of Mumbai and Kolkata also recorded poor levels of air pollution.
According to IQAir, a Switzerland-based climate group that is also a technology partner of the United Nations Environmental Program(UNEP) has listed Mumbai and Kolkata are in the top ten most polluted cities of the world.
While Delhi tops the list with an AQI of 460 as listed by the IQAir service, Kolkata ranks sixth and Mumbai fourt in the entire list. The cities with the worst AQI indices also include Lahore, in Pakistan, and Chengdu, in China.
Here are the ten cities with the worst air quality indicators and pollution rankings, according to IQAir:
City Country AQI
1Delhi, India, 460
2 Lahore, Pakistan, 328
3 Chengdu, China, 176
4 Mumbai, India, 169
5 Karachi, Pakistan, 165
6 Kolkata, India, 165
7 Sofia, Bulgaria, 164
8 Dhaka, Bangladesh, 160
9 Belgrade, Serbia, 159
10 Jakarta, Indonesia, 158
The System of Air Quality and Weather Forecasting And Research (SAFAR) under the Ministry of Earth Science reported that the air quality is in the 'very poor' category in Delhi with an air quality index (AQI) of 390.
According to an analysis by the Delhi Pollution Control Committee, people in Delhi breathe the worst air between November 1 and November 15 every year. The city has recorded severe air quality on six of the last eight days after Diwali.
Faridabad (460), Ghaziabad (486), Greater Noida (478), Gurgaon (448) and Noida (488) also recorded severe air quality at 4 pm on Friday.
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".
A layer of eye-stinging smog lingering over Delhi-NCR thickened on Friday, giving an orange tint to the sun and lowering visibility to 200 metres at several places in the region.
India Meteorological Department officials said moderate fog and low temperatures in the morning -- a low of 12.6 degrees Celsius on Friday -- and calm winds have been trapping pollutants close to the ground.
"Visibility levels at the Indira Gandhi International Airport and the Safdarjung Airport dropped to 200-500 metres due to moderate fog. It intensified on Friday due to high humidity," an official said.
