Air high quality: Delhi breathes 12 months’s cleanest air, first ever ‘good air’ day recorded in October

 

NEW DELHI: Monday’s heavy in a single day rain achieved what this 12 months’s monsoon couldn’t — produce a “good air” day for Delhiites, the primary in 2021, and the primary in October because the air high quality index started in 2015. The metropolis’s common AQI on Monday was 46, getting into the “good” zone (under 50) for the primary time in 14 months.

The enchancment in air high quality in a span of 24 hours couldn’t have been extra dramatic. On Sunday, Delhi’s AQI had hovered near the “very poor” class (above 300) at 298, with a poisonous haze enveloping town the day earlier than. As air high quality often begins falling from mid-October, specialists mentioned a clear air day throughout this time was extremely “unusual”.

Data from the Central Pollution Control Board, which started measuring AQI from 2015, shows good air days are rare in Delhi. Not a single such day was reported in 2015, 2016 and 2018. Rarer still are good air days outside the monsoon season, with just one recorded since 2015, prior to Monday.

In 2017, there were two “good air” days, on July 30 and 31. Two days were reported in 2019 as well — August 18 and 19.

Last year, Delhi saw five good air quality days — one in March following the total Covid lockdown and four in August.

V K Soni, head, environment and research centre, India Meteorological Department (IMD), said, “Good rainfall recorded in Delhi and neighbouring states, including Uttar Pradesh, Haryana and Uttarakhand, helped wash out pollutants, pushing the city’s AQI in the ‘good’ category.”

Anumita Roychowdhury, executive director research and advocacy, Centre for Science and Environment, said, “A good air day in October is unusual due to the onset of winter conditions that trap pollution. A good air day (based on AQI) is elusive in the capital and a few that occur happen largely during monsoon period.” She added, “This October, however, delayed and intense rains in the region have washed out pollutants. But pollution will bounce back soon. We need to be prepared.”

System of Air Quality and Weather Forecasting And Research (SAFAR), the forecasting body under the Union ministry of earth sciences, said, “Delhi’s AQI is in the good category with PM2.5 as the main pollutant. Local land surfaces are wet and so dust re-suspension is minimum which led to low PM10. Presence of western disturbance has led to scattered rainfall over north India, leading to low biomass burning. This condition improved AQI with low PM2.5. Fire counts have reduced to 170 and its share is only 1% to PM2.5.”

Experts warned that the air quality is likely to deteriorate in the next two days. SAFAR said, “Moist surfaces inhibit re-suspension of dust which will keep AQI in ‘good’ category for the next 24 hours. After that, AQI will degrade to ‘satisfactory’ for Delhi.”

L S Kurinji, programme associate, Council on Energy, Environment and Water (CEEW) said, “In the coming weeks, with changes in meteorological conditions, emissions from local and regional sources would only cause deterioration in air quality. The Delhi government should roll out pre-emptive measures in advance to keep the capital’s air quality levels under check.”

Source TGI