Delhi’s air remained in the “severe” category for a third consecutive day on Sunday, with an Air Quality Index (AQI) of 402 according to the Central Pollution Control Board’s 4pm daily bulletin, as the speed wind remains weak in the region.
As agencies plan a temporary respite over the next two days with an increase in wind speed that could help disperse pollutants in the area, the wind speed will drop again from December 1, maintaining the quality of largely looked between the “very bad” and “severe” categories. .
An AQI between 0 and 50 is considered “good”, 51 and 100 “satisfactory”, 101 and 200 “moderate”, 201 and 300 “poor”, 301 and 400 “very bad”, and 401 and 500 “severe” .
Delhi recorded an AQI reading of 402 (severe) on Saturday and 406 (severe) on Friday. Thursday, AQI Delhi had touched the 400, on the verge of the “severe” category.
Gufran Beig, founder and project manager at Air Quality and Weather Forecasting and Research System (Safar), said the wind speed has become “calm” in the past 72 hours, but is expected to increase from Monday. âWe expected relief from November 29 and the wind speeds will remain good during the day of November 29 and 30. However, conditions will become unfavorable again from December 1 as the wind speed and temperatures decrease, also causing drop the ventilation index, âBeig said.
According to Safar, only around 200 farm fires were recorded on Sunday in the northern plains, with Delhi’s share of their contribution to PM2.5 set at just 3%. PM 2.5 are fine inhalable particles with a diameter of 2.5 microns. It is about 30 times smaller than a human hair.
According to the Early Warning System (EWS) for Delhi, a forecasting mechanism under the Ministry of Earth Sciences, the Delhi ventilation index is also expected to improve significantly over the next two days, allowing for more rapid dispersion of pollutants. While it was 2,500 m2 / s on Sunday, it could increase to 7,500 m2 / s on Monday and 6,000 m2 / s on Tuesday.
“A ventilation index of less than 6,000 m2 / s with average wind speeds of less than 10 km / h is unfavorable for the dispersion of pollutants,” EWS said in its daily bulletin on Sunday.
Delhi recorded a minimum temperature of 10.8 degrees Celsius on Sunday, with the mercury expected to stay around 10 degrees Celsius on Monday as well. While it could dip below the 10 degree mark on Tuesday, the influence of a western disturbance could bottom out to 12 degrees Celsius by Wednesday, according to forecasts from the Indian Meteorological Department (IMD).
Delhi on Sunday recorded a maximum temperature of 26.8 degrees Celsius, one degree above normal. Its maximum temperature is expected to hover between 26 and 27 degrees Celsius over the next three days, IMD said.
âShallow fog with a visibility range of 500 to 1,000 meters was reported in the early hours of Sunday. Shallow fog will continue to pass through Delhi over the next few days, âsaid a Met official.