Top

Pre-lockdown pollution back with a bang

This analysis has dispelled the myth about safer air in the south compared to other regions

Hyderabad: A new analysis of winter pollution in India’s five southern states until January 26, 2021, carried out by Centre for Science and Environment (CSE), has revealed some startling details.

It states that clean air, courtesy of lockdown and monsoon period, has now been lost since economy got reopened and after winter set in. Levels of higher particulate matter 2.5 microns in thickness (PM 2.5) are being witnessed, which are typical when there are continuous emissions, including from vehicles, industry, and construction. PM 2.5 gets trapped due to meteorological changes.
Anumita Roychowdhury, executive director in charge of CSE’s Research and Advocacy said: “This analysis has dispelled the myth about safer air in the south compared to other regions. Health impacts are almost equally bad. Despite the dramatic reduction in air pollution during lockdown, pollution has bounced back across the southern region, unmasking the high impact of local and regional pollution.”

After assessing the changing trends in Indo-Gangetic plains, Delhi-NCR, Rajasthan, Maharashtra, and West Bengal, this analysis unravels the pattern of pollution in cities of southern India – a vulnerable but poorly monitored region from the air quality perspective.

Avikal Somvanshi, programme manager in CSE’s Urban Lab team of Sustainable Cities programme, said: “Winter is not as harsh in southern cities. Therefore, the impact of inversion is expected to be limited; yet a build-up of pollution has been noted. Even though the average level of PM 2.5 for summer and monsoon months in 2020 is considerably lower than the previous year due to the summer lockdown, PM 2.5 levels this winter have risen beyond those in 2019 in most of the monitored cities, Chennai and Thiruvananthapuram being the only exceptions. The region cannot rely only on the natural advantage of warmer winters and sea breeze to avoid bad air.”

The analysis is based on publicly available granular real-time data (15-minute averages) from the Central Pollution Control Board’s (CPCB) official online portal Central Control Room for Air Quality Management.

The study notes that while several bigger cities have witnessed reduction in annual trends in PM 2.5, smaller towns and cities have experienced an increase. Only nine out of 21 cities have data for 2019. The 2020 average PM 2.5 level in many inland cities in Deccan Plateau has climbed up to breach the average concentration recorded in 2019.

Chikkaballapur in southern Karnataka is the worst performer with 3.9 per cent increase from 2019 level. Tirupati has registered a 1.8 per cent increase. The maximum improvement is noted in Chennai, which closed 2020 with a 30 per cent lower PM 2.5. Amravati has 24 per cent, Bengaluru 19, Visakhapatnam 16, and Hyderabad and Rajamahendravaram at 14 per cent are the other best performers in the pool. Thiruvananthapuram has shown an improvement of 5 per cent.

The dirtiest week for Hyderabad, Amravati, Rajamahendravaram, Chikkaballapur, and Yadgir was the week ending on January 3, 2021. For Tirupati, Visakhapatnam, Hubballi, Chennai, Coimbatore, Kannur, Kozhikode, Kochi, and Thiruvananthapuram; the dirtiest week was that ending on December 27, 2020. Hyderabad and Visakhapatnam had earlier start with bad air days in 2020 winter. The rolling weekly average rose over the 24-hour standard or 60 μg/m3 in Visakhapatnam on October 23 (nine days earlier), and Hyderabad on October 25 (14 days earlier).

This winter overall has been 34 per cent dirtier in Visakhapatnam, seven per cent in Hyderabad, and nine per cent in Thiruvananthapuram. Bengaluru registered no change in the seasonal average while Chennai was 20 per cent cleaner. The rolling weekly average did not breach the standard in Bengaluru, Chennai and Thiruvananthapuram.

Next Story