Three U.P. cities rival Delhi AQI, figure on worst list: CPCB data

On a day when Delhi saw a spike in air pollution, recording Air Quality Index (AQI) of 494, three cities of Uttar Pradesh figured in the top cities of the country that recorded the worst air quality on Monday, Central Pollution Control Board (CPCB) data read.
Ghaziabad (severe 438), Noida (severe 423) and Hapur (severe 431) recorded the most polluted air in the country on Monday.
AQI above 401 is categorised as severe, which not only affects healthy people but severely harms those with pre-existing breathing issues, as well as children and the elderly.
Particulate matter, including PM2.5 and PM10 along with vehicular and industrial emissions, comprised the major pollutants that contribute to higher AQIs.
According to experts, cold weather also contributed to these factors and led to higher AQIs.
Besides these, several UP cities, specially in the west UP region including Bulandshahr recorded AQI above 301 mark that is categorised as ‘very poor’.
Experts said particulate matter takes longer to settle down in cold weather as the air becomes dense, causing a rise in AQI and smog formation.
Background pollution caused by burning of farm waste in neighbouring states also contributes towards air pollution, especially in the west UP region, officials of Uttar Pradesh Pollution Control Board said.
Meanwhile, experts of the State Pollution Control Board said that vehicular, industrial emissions and dust particles are major contributors of air pollution in the state capital. The dip in temperature also added to the trouble making the air denser.
Why the worsening air
According to experts the dip in air quality during winter occurs primarily due to the formation of a high pressure zone caused by a dip in average temperatures.
“The fall in temperature builds a high pressure zone and limits the flow of air. This results in a stagnation effect and pollutants remain suspended in air within a limited space for longer duration,” said Rajat Singh, a senior meteorologist. “The conditions worsen with rise in use of vehicles, burning solid fuel and bursting of crackers,” he added.