Delhi’s air quality turns ‘moderate’
NEW DELHI: The air quality in the national capital i mproved slightly on Sunday, two days after being recorded in the ‘poor’ category. The air quality improved to ‘moderate’ as wind speed picked up marginally during the day. While air quality in Noida was also moderate, it remained ‘poor’in Gurugram.
Meanwhile, the maximum and minimum temperatures also fell on Sunday. The day temperature which was recorded at 34 degrees Celsius fell slightly against yesterday’s 34.6 degrees Celsius while the minimum temperature was recorded at 20.2 degrees Celsius, two notches below normal.
Delhi’s air quality index (AQI) value was recorded at 181 in the moderate category as against 256 on Friday.
Scientists in the Central Pollution Control Board (CPCB) attributed the improvement to favourable meteorological conditions.
The AQI values in Gurugram and Greater-noida remained in the poor category at 297 and 234, respectively. “Though wind conditions remained calm, little improvement in wind speed dur- ing the day as well as control measures and less activity, (Sunday) being a holiday, helped improve air quality slightly. Also, because when it did turn ‘poor’ on Friday and Saturday, it had marginally breached the moderate category hovering around 256 and 209, respectively. As per inputs received from the MET department, weather conditions are expected to remain favourable on Monday as well,” said a senior CPCB official.
Also, the official said, these changes in wind conditions are normal at this time of the year as October is a period of transition and hence meteorological conditions keep fluctuating. The wind pattern will become stable once winter sets in during November, the official said.
On a scale of 0 – 500, an AQI value between 200 and 300 is considered ‘poor’ while a value between 300 and 400 is considered ‘very poor’. Anything beyond 400 is considered ‘severe’.
Delhi usually encounters ‘severe’ air quality in November. In the winter of 2017, Delhi encountered a week-long spell of smog following which the AQI value in the city hit a peak of 486 on November 9. In winter of 2017, AQI in Delhi had hit a peak of 486.