Delhi's Air Quality "Satisfactory" In July. Reason: Surplus Rainfall

Delhi recorded 24 "satisfactory" air quality day this month on account of surplus rainfall, making it the cleanest July for the city since 2015 when the Central Pollution Control Board started maintaining AQI data.

The average air quality index this July stood at 87. Only July 2020 was better with an average AQI of 84 -- the city had recorded a significant decline in pollution levels that year due to the strict lockdown to prevent the spread of Covid.

Delhi had logged 25 'satisfactory', four 'moderate' and two 'poor' air quality days in July 2020.

Air quality index (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", and 401 and 500 "severe".

The capital did not record a single poor, very poor or severe air quality day this July.

The city had registered an average AQI of 100 in 2021; 134 in 2019; 104 in 2018; 100 in 2017; 144 in 2016 and 138 in 2015, according to CPCB data.

The Safdarjung observatory, Delhi's primary weather station, recorded 19 rainy days, highest in at least a decade, and 286.3 mm of rainfall against a normal of 209.7mm this month.

Overall, the city has received 310.8mm of precipitation against a normal of 283.8mm since June 1 when the monsoon season starts.

Delhi also recorded a dip in maximum temperatures this month due to surplus rainfall. The average maximum temperature stood at 35.36 degrees Celsius, the lowest since 2017.