The air quality in Delhi slipped to the 'very poor' category on Monday because of a steep rise in crop residue burning emissions, according to the location-specific air quality monitoring system. The national capital recorded an Air Quality Index (AQI) of 302 with PM 2.5 as the lead pollutant.
As per the System of Air Quality and Weather Forecasting and Research (SAFAR), a system introduced by the Ministry of Earth Sciences to measure air quality, the share of crop residue burning emissions in PM 2.5 was nearly 8 percent in Delhi.
On Sunday, the India Meteorological Department (IMD) had predicted that the air quality in the national capital will drop to the 'very poor' category on November 1-2. "The air quality is likely to remain in the lower end of the very poor category till November 4 and then deteriorate on November 5-6 significantly. PM 2.5 to be the predominant pollutant," IMD said.
For the past five days, Delhi's air quality has been 'poor'. In its bulletin on October 28, SAFAR stated, "Effective fire count of stubble burning in the northwest region of Delhi is 656 and its share in PM 2.5 is 16 percent as transport-level winds are northwesterly."
Prior to this, the Indian Agricultural Research Institute (IARI) data had revealed that as many as 1,948 farm fires were recorded on October 15-16 as against 1,795 incidents in an entire month till October 14.
The air quality in Delhi is likely to "improve to the upper end of poor" due to an expected change in wind direction, according to SAFAR. The wind direction is expected to change from northwesterly to westerly or south-westerly, reducing the transport of emissions from stubble burning.
Meanwhile, isolated rain in the upwind region is also expected to improve air quality in Delhi. However, there seems to be no relief for Delhiites from the air pollution till November 6.
An AQI within the range of 0-5 is regarded as 'good', 51-100 is 'satisfactory', 101-200 is 'moderate', 201-300 is 'poor' and 301-400 is 'very poor' and 401-500 is considered 'severe'.
