Despite the partial restrictions on various sectors across Delhi- NCR due to lockdown implemented in the wake of Covid-19 pandemic, the pollution levels have still increased, reveals Centre for Science and Environment (CSE) on this World Environment Day.
According to CSE, the latest results of air quality analysis show how air quality trend has changed through the successive seasons during the pandemic times in Delhi and National Capital Region (NCR).
This assessment period is from September 2018 to May 2021 that captures three successive winter seasons, pre and pandemic era and different stages of lockdown in Delhi and the NCR.
This reaffirms that while there has been substantial drop in PM 2.5 levels during both the hard lockdown phases in March to May in 2020 and April-June, 2021 with nearly similar levels evoking imagery of blue sky, the early months of 2021 or the springtime has witnessed worsening.
“This indicates that despite the partial restrictions the pollution levels have increased. While the reason needs investigation, it is important to underscore that there would be a rebound effect with full opening of the economy and intensification of traffic. Pandemic management during the second wave may have slowed down action but this has to speed up to prevent the rebound effect or retaliatory emissions to ensure longer term air quality gains”, says Anumita Roychowdhury, executive director-research and advocacy, CSE, and the head of its sustainable urbanisation, air pollution and mobility programmes.
This is particularly important given the new science on the linkage between air quality and its effect on vulnerability to the pandemic.
“The key highlight is that the spring time – January to March, when pollution level begins to subside after winter, PM2.5 this year has recorded highest seasonal levels compared to the corresponding period in preceding years including the normal year of 2019,” says Avikal Somvanshi, programme manager in CSE’s Urban Lab team of the Sustainable Cities programme.
This analysis is based on the real time data available from the current working air quality monitoring stations in Delhi and NCR
As far as data availability is concerned, there is a wide variation between monitoring locations. While over 90 per cent of hourly data is available for all Delhi Pollution Control Committee (DPCC) and Central Pollution Control Board (CPCB) stations for the period between 1 January to 31 May, 2021, data availability for two IITM stations is 75-86 per cent.
Pollution control board stations in Gurugram shows over 90 per cent data availability, but the stations in Faridabad has only 70-89 per cent data available. UPSPCB stations in Noida, Ghaziabad and Greater Nodia have over 85 per cent data available except the stations at Noida Sector 125 and Greater Noida Knowledge Park-III which have just 65 per cent data.
Overall, monitoring network strength in Delhi and big five NCR cities has come down from 58 stations to 48 stations now. This along with the lower availability of data is a matter of concern as this makes the investments in monitoring networks sub-optimal.