After 9 months of pollution, Delhi has a ‘good’ air day on Thursday
According to the SAFAR app, Delhi’s overall Air Quality Index on Thursday was 77. When AQI is below 100, the air quality is considered good and air pollution poses little or no risk. On Friday, too, the AQI is expected to be 85 and it is likely to remain in the same range for the next one week.Updated: Jul 13, 2017 23:15 IST
After a nine-month gap, Delhi breathed ‘good’ air on Thursday. The air on Friday may also remain good, as per the forecast by Ministry of Earth Science’s System of Air Quality and Weather Forecasting And Research (SAFAR) app.
According to the SAFAR app, Delhi’s overall Air Quality Index on Thursday was 77. When AQI is below 100, the air quality is considered good and air pollution poses little or no risk. On Friday, too, the AQI is expected to be 85 and it is likely to remain in the same range for the next one week.
According to experts, the decrease in pollution levels in the is due to the rainy season in North India.
“Even though it is not raining in Delhi at the moment, in surrounding areas it is pouring down. Because of this, long range transport of pollutants from outside Delhi is minimal. Around 20%-30% pollution gets reduced because of this,” SAFAR chief Gufran Beig told HT.
“Because of the monsoon, there is lot of moisture in the air. This is also another reason for this decreasing pollution levels over the past 2-3 weeks,” Beig said.
However, as per the Central Pollution Control Board AQI standards the air quality on Thursday was under the ‘satisfactory’ range. As per the CPCB data, Delhi did not have even a single day of good AQI for the past 26 months. As per the CPCB barometer, air quality falls in the good range if it is 50 or less. The satisfactory range falls between 50-100.
“We were expecting the result to be ‘good’ but three monitoring stations, Anand Vihar, ITO and Delhi College of Engineering in Bawana, which are heavy traffic zone, ruined the results. The air quality was good in the city on Thursday as mixing height was higher compared to other days,” Dr Dipankar Saha, additional director and head of the Air Laboratory at the CPCB told HT.
According to him, the weather conditions, which is not too hot and on the cooler side, also aided in the good air quality.
The 24-hour rolling average of PM10 and PM2.5 were recorded at 77 and 44μg/m3 respectively on Thursday, according to SAFAR. PM2.5 and PM10 are ultra-fine particles that are the dominant pollutants in Delhi. The acceptable levels of PM 2.5 and PM10 are 60 and 100 microgram per cubic metre, respectively.
Locality wise, Ayanagar had the best air quality with 64 AQI and a forecast of 68 on Friday. At Pitampura, Airport, Dhirpur and Delhi University, the AQI recorded were 80, 82, 83 and 90. On Friday, these areas may record an AQI of 87, 88, 78 and 82.
At Pusa, Lodhi Road and Mathura Road, however, the AQI was moderate with 115, 108 and 115.
On Friday, however, these are expected to be good with predictions of 98 for all three stations.
Delhi, a city of 20 million people, is among the world’s most polluted cities according to the World Health Organisation. It has been struggling to clean up a toxic cocktail of dust, smoke and gases from its air.