Marginal improvement in Delhi’s air quality; remains in severe zone

Scientists said the pollution levels have increased because of low wind speed and dipping temperature, which have trapped pollutants closer to the ground

There was a marginal improvement in Delhi’s air quality on Thursday morning even as it remained in the severe zone at 7am. The hourly Air Quality Index (AQI) at 7am was 429. According to the Central Pollution Control Board (CPCB) data, the overall AQI on Wednesday and Tuesday was 433 and 418, in the severe category.

According to the Central Pollution Control Board data, the overall AQI on Wednesday and Tuesday was 433 and 418, in the severe category. (Sanchit Khanna /HT PHOTO)

Scientists said the pollution levels have increased because of low wind speed and dipping temperature, which have trapped pollutants closer to the ground.

VK Soni, head of India Meteorological Department’s Environment Monitoring and Research Centre, said the wind speed did not pick up during the day on Wednesday which led to the accumulation of pollution particles.

“The wind speed was largely calm through Wednesday... The forecast says that the AQI will remain in the severe zone on Thursday too,” Soni said. “The prominent pollutant has been PM 2.5. The contribution of larger particles has been less in the pollution over the last few days.” Soni said there is a possibility of marginal improvement in wind speed from December 25, which is likely to bring down the high pollution levels.