New Delhi, November 18 (Language) Delhi’s air quality has improved due to increase in wind speed and change in wind direction at night, but it is still in the ‘very poor’ category. This information was given by the monitoring agency.
Delhi’s air quality index (AQI) was 339 at 9 am, which was 405 at 4 pm on Friday. The 24-hour average AQI, recorded at 4 pm every day, was 419 on Thursday. It was 401 on Wednesday, 397 on Tuesday, 358 on Monday, 218 on Sunday, 220 on Saturday and 279 on Friday.
The relatively better air quality last weekend was attributed to rain. Air pollution levels increased due to resurgence in incidents of bursting of firecrackers and stubble burning in neighboring states on Diwali night. Also, the increase in air pollution was attributed to adverse meteorological conditions which mainly included calm air and low temperatures.
Neighboring Ghaziabad (274), Gurugram (346), Greater Noida (258), Noida (285) and Faridabad (328) also recorded air quality ranging from ‘very poor’ to ‘severe’.
An AQI between zero and 50 is considered ‘good’, 51 and 100 ‘satisfactory’, 101 and 200 ‘moderate’, 201 and 300 ‘poor’, 301 and 400 ‘very poor’, 401 and Anything between 450 is considered ‘severe’ and anything above 450 is considered ‘very serious’.
Recent findings of a joint project of the Delhi government and the Indian Institute of Technology (IIT), Kanpur, showed that vehicular emissions contributed to about 45 per cent of the capital’s air pollution on Friday. It is likely to reduce to 38 percent on Saturday.
The second major contributor to Delhi’s bad air is particles like sulphate and nitrate that form in the atmosphere due to the interaction of pollutant particles and gases emitted from sources such as power plants, refineries and vehicles. During the last few days, their contribution to Delhi’s air pollution has been 19 to 36 percent.
An India Meteorological Department (IMD) official said the improvement in wind speed from November 21 could lead to reduction in air pollution levels.
Delhi’s air quality has deteriorated in the last few days despite strict measures taken by the Delhi government, including a ban on construction work and entry of diesel-guzzling trucks in the national capital.
Language Amit Santosh