The air quality of the National Capital improved marginally on Wednesday to ‘very poor’ after remaining in the ‘severe’ category for two consecutive days. Also, parts of Delhi-NCR have received light rainfall since Tuesday evening.

However, government agencies have forecast that chances of any significant improvement in air quality over the next few days are remote, as meteorological conditions are not favourable for dispersion of pollutants.

A multi-agency task force, headed by the Central Pollution Control Board (CPCB), has asked government agencies to carry out special pollution-control drive and enforce corrective actions particularly in areas where the air quality remained severe. At least 27 such areas have been identified out of which 19 were in Delhi.

The air quality index (AQI) on Wednesday was recorded as 392 at 4pm against Tuesday’s 413. Even though the overall AQI was ‘very poor’, many of the city’s 36 monitoring stations recorded ‘severe’ air quality. These include Anand Vihar, Ashok Vihar, Bawana, Narela, Burari, Sonia Vihar and Wazirpur, among others.

On a scale of 0 – 500, AQI value between 401 and 500 is considered to be ‘severe’ level of pollution. According to the CPCB such high levels of pollution can affect healthy people and seriously impact patients with lung and heart ailments.

“The air quality is likely to remain in the upper end of the ‘very poor’ category over the next few days. This is mainly because the surface wind speed, high moisture levels and ventilation index are highly unfavourable for dispersion of pollutants trapped in the air,” said a scientist of the government’s early warning air quality forecasting system.

According to CPCB officials, wind speed has picked up marginally, but high moisture content is allowing further trapping of local pollutants.

Meanwhile, officials in the India Meteorological Department (IMD), said, 1.4 mm rainfall was recorded on Wednesday at the Safdarjung observatory — which represents Delhi’s weather.

Maximum temperature on Wednesday was recorded as 21.6 degrees Celsius, two notches below the season’s average. The minimum temperature settled at 12.6 degrees Celsius, four notches above normal.

However, the minimum temperature is expected to fall from Thursday to around 7 degrees Celsius.

“Very light rainfall is likely to occur on Thursday morning as well. The minimum temperature had risen because of the western disturbance passing through Delhi. It is expected to drop again from Thursday, with the wind direction changing to northwesterly bringing cold and strong winds,” said a senior IMD official.

First Published: Dec 13, 2018 10:53 IST