National

Air pollution dips, in unintended upside to lockdown

Annapurani V Chennai | Updated on March 25, 2020 Published on March 25, 2020

A traffic policeman on the deserted Avinashi Road in Coimbatore on the first day of the national lockdown on Wednesday. Photo: S. Siva Saravanan   -  The Hindu

Air quality improves dramatically in all four metros

There is actually a positive side to the lockdown: The air quality has improved vastly after the shutting down of industrial activity and halt in all forms of commuting.

Unhealthy category

According to data from the Central Pollution Control Board (CPCB), as of 4 pm on Tuesday, only two cities — Lucknow (204) and Muzaffarpur (273) — recorded air quality index (AQI) levels over 200, which is categorised as ‘very unhealthy’.

Thirty-six of the 110 places for which data were available on the CPCB website recorded ‘Unhealthy for sensitive groups’ index values (101 to 150). Six places, including Faridabad (187) and Meerut (171) recorded index ‘Unhealthy’ values (151 to 200).

Udaipur, Patiala, Jalandhar and Chandigarh were among the places that recorded air quality index levels of 0 to 50. The majority — that is nearly 55 of the 110 places for which data were available on the CPCB website — recorded an air quality index in the ‘moderate’ category (51 to 100).

Data this afternoon (at 1:15 pm) on the AQI India website showed that among the top cities, Ahmedabad recorded the highest air quality index reading, at 100, followed by Kolkata (73), Mumbai (65), Hyderabad (63), Pune (50), Bengaluru (46), New Delhi (42) and Chennai (25).

Even before Prime Minister Narendra Modi’s lockdown announcement on Tuesday night, the Tamil Nadu government had imposed Section 144 in the State, which also restricted public and private transport, including autorickshaws, taxis, and all inter-district and inter-State transport buses.

With most companies across the country asking employees to work from home, private vehicles, too, were off the road. The AQI India website showed that pollution levels have been declining in most cities over the past seven days, thanks to the reduced travel.

Among the top four metros, Delhi, Mumbai, Kolkata and Chennai, AQI in Delhi fell from 300 on March 21 (the highest in the past seven days) to 40 on March 24.

In Mumbai, it was the highest (306) on March 21, and the lowest (36), on March 22.

Kolkata recorded the highest AQI (191) during the past seven days on March 19 and the lowest (33) on March 23 and March 24.

In Chennai, the AQI reading was the highest (274) on March 22, and the lowest (25) on March 21 and March 25.

 

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Published on March 25, 2020
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