New Delhi: Noise level declined in Delhi this Diwali as compared to last year, but the air pollution rose marginally due to more smoke-producing fircrackers.
A report released by Central Pollution Control Board (CPCB) board on Wednesday also attributed high air pollution level during Diwali to adverse meteorological conditions in and around the Capital.
"Air pollutant levels during 2012 Diwali were found to be higher as compared to Diwali-2011, which can be attributed to adverse meteorological conditions or bursting of less noisy but more smoke-producing crackers," a CPCB official said.
While Delhi, Bangalore, Kolkata and Hyderabad showed a decreasing trend in real time noise level, no change in sound- level is observed in Mumbai, the report said.
"However, sound level at Lucknow and Chennai showed slight variation in comparison to Diwali-2011," it added.
CPCB this year conducted the Real Time Continuous Ambient Noise Monitoring at 35 locations in seven cities such as Delhi, Mumbai, Chennai, Kolkata, Lucknow, Bangalore and Hyderabad.
For higher air pollution level, the report listed out some meteorological conditions such as decrease in average temperature, low wind speed, less night time mixing height and increase in humidity profile from 39 per cent in 2011 to 68 per cent this year.
"Sulphur dioxide concentration on Diwali-2012 increased at nine locations... Nitrogen dioxide concentration increased at all the locations as compared to 2011... Particulate Matter levels have also shown an increasing trend at all locations on Diwali this year as compared to 2011," the report said.