New Delhi, November 27: Low wind speed and falling temperature has turned up pollution levels in the National Capital Region on Sunday, with the air quality expected to get worse over the next few days, experts in Delhi said to media.
On Sunday, the average daily Air Quality Index (AQI) rose to 352 from 322, which was recorded on Saturday. AN AQI value between 301 to 400 is considered as “very poor”. On November 9, the AQI had hit a peak of 486 when pollution levels in Delhi stayed in the “severe” zone for a week, leading to a public health emergency.
According to a report, levels of particulate matter – the primary pollutants in Delhi’s air – were also on the rise. On Sunday evening the PM10 reading shot up to 370 ug/m3 at 7 pm from 276 at 3 pm.
The level of the smaller and deadlier PM 2.5 particulate matter also hit 226ug/m3 on Sunday from 171 the previous day. It is quite noteworthy that PM 2.5 level of 300 and above falls in the emergency “severe” zone.
“The reason behind the rising pollution level is the falling wind speed and increasing moisture levels. In last 24 hours, the wind speed dropped from around 7 km per hour on Saturday to less than 3 km per hour per hour on Sunday. Due to this, pollutants are accumulating again as the winds with very low speed are not being able to flush them out,” the Central Pollution Control Board (CBCB) said to media.
Officials working at the Regional Weather Forecasting Centre (RWFC) said that they were expecting foggy days later this month because of the rising moisture levels.
“In next two-three days, more moisture and low wind speeds could lead to fog. Visibility is likely to drop to less than 1 km,” a senior scientist at RWFC said to Hindustan Times.
SAFAR, India’s pollution forecasting agency, is also predicting a dip in air quality over the next two or three days.
On Friday the minimum temperature of the National Capital Region had dropped to a season-low 7.6 degrees Celsius and on Sunday it was recorded 8.5 degrees.