Air quality ‘poor’ in Delhi, worse days ahead

Air in Delhi got a bit cleaner on Tuesday but worse days are yet to come.

Air quality in Delhi finally became cleaner on Tuesday but more bad days are yet to come.

While the Air Quality Index is hovering in very poor range, the 24-hour rolling average of PM 10 and PM 2.5 touched moderate on Tuesday morning, according to System of Air Quality Weather Forecasting and Research (SAFAR) data.

While the Air Quality Index is hovering in very poor range, the 24-hour rolling average of PM 10 and PM 2.5 touched moderate on Tuesday morning, according to System of Air Quality Weather Forecasting and Research (SAFAR) data.

Air in Delhi got a bit cleaner on Tuesday but worse days are yet to come.

While the Air Quality Index is hovering in the very poor range, the 24-hour rolling average of PM10 and PM2.5 was moderate on Tuesday morning, according to System of Air Quality Weather Forecasting and Research (SAFAR) data.

On Tuesday morning, PM10 was 152 microgram per cubic metre while PM 2.5 clocked 70. Later in the day, however, it became poor with PM10 reaching 270 microgram per cubic metre while PM 2.5 touched 107. In the evening, the two increased to 312 and 132 microgram per cubic metre, respectively.

PM2.5 and PM10 are ultrafine particles — the dominant pollutants in Delhi. The 24-hour prescribed standards of PM 2.5 and PM10 are 60 and 100 microgram per cubic metre respectively.

Read: Let’s fight pollution: Smog over, but the battle against Delhi’s toxic air isn’t

However, the pollution levels are expected to plummet over the next few days. Gufran Beig, the country’s leading atmospheric scientist, told Hindustan Times that strong winds are responsible for the cleaner air in the city, which usually is more polluted in the winter. The air quality is expected to become very poor in few days once the wind speed becomes falls and will remain foul till February, he said.

“The air quality this time in Delhi is much better than a typical winter, when the pollution level increases. The moment the wind stops, the air quality might go back to being ‘very poor’,” Beig said.

The main factors that influence Delhi’s air quality are wind speed and direction.

A MeT official said the climatic factors that led to good visibility and concurrently good air quality over Delhi NCR for past fortnight are changing. “The winds have become calm today (Tuesday) and are likely to be easterly, north easterly from November 30 to December 3. This will contribute to increase in moisture and reduction in visibility over the Indo-Gangetic plain,” he said.