KATHMANDU: Along with extreme cold, the air pollution in Kathmandu Valley has also increased.

According to the Air Quality Index (AQI), the air pollution level in Kathmandu Valley was 250 AQI on Monday.

According to environmentalist Bhushan Tuladhar, air pollution is more likely to increase during winter than in summer.

“During the cold season, as the cold air stays close to the surface of the ground for a long time, the possibility of pollution is high, and as the temperature rises in the afternoon, the pollution spreads in the air,” he said.

Apart from that, he said that the practice of burning garbage, tires and firewood during the cold season also helps to increase the pollution.

Based on AQI, Kathmandu Valley ranks as the fifth most polluted city in the world today.

Pakistan’s Lahore tops the list. AQI of Lahore is 341. In addition, the AQI of India’s Kolkata is ranked in the second place with an AQI of 248, and the AQI of Ulaanbaatar in Mongolia is 238. Also, the fourth most polluted city in India, New Delhi, has an AQI of 227 AQI.