Brace for severe smog in coming days, consider counter measures like reducing traffic on road, says CSE – ET Auto
It correlates well with the lower pollution level in Delhi-NCR. First the good news. Stubble burning in the farms in neighboring states, which is a major contributor to Delhi‘s winter air pollution, has been less than half in the run up to the cold this year so far as compared to last year. This alongwith an extraordinarily wet monsoon which also withdrew later than usual meant Delhi got its cleanest air during the monsoons and early autumn in the last four years. Now the bad part. The delayed withdrawal may have impacted stubble burning in the northern states but is likely to pick up in the next few weeks. Concentrated over a shorter span, it would be more intense which may mean more severe peak in pollution for the capital city. Brace yourself, says Delhi based NGO Centre for Science and Environment, which put out a study analysing air pollution trends in Delhi and the broader Indo-Gangetic belt over the last few years. Delhi and the larger region will require urgent action to prevent severe smog episodes. Reduce traffic volume, eliminate waste burning, eliminate dirty industrial fuels, and implement stringent dust control measures especially in the construction sector Anumita Roychowdhury, Executive Director, Research & Advocacy, CSE The 2021 winter is starting with a cleaner threshold compared to the previous years, largely due to the intense and prolonged effect of the monsoons. While winter pollution cannot be predicted at this moment, the evidence of rising summer pollution in 2021 despite the lockdown and the evidence of a synchronised effect of winter pollution across the Indo-Gangetic Plain add to our concern,” says Anumita Roychowdhury, executive director, research and advocacy, CSE. “Delhi and the larger region will require urgent action to prevent severe smog episodes. Reduce traffic volume, eliminate waste burning, eliminate dirty industrial fuels, and implement stringent dust control measures — especially in the construction sector.”The extraordinarily wet monsoon this year has translated into the cleanest season for Delhi in the last four years. The city-wide average for the monsoon this year stood at 41 microgramme per cubic metre (ug/m3), with 96 days meeting the 24-hour standard for PM2.5. There was a progressive increase in the number of cleaner days with an average 6 per cent annual improvement since 2018. In Delhi, Dr Karni Singh Shooting Range recorded the lowest seasonal average of 33 ug/m3, while the National Stadium had 100 days that met the daily standard. Anand Vihar, with a seasonal average of 61 ug/m3 had lesser number of days – 54 — meeting the standard and was the worst hotspot in the city. So far in the post monsoon autumnal period, things are looking good. The farm fire count during the pre-winter season of 2021 has been less than half of the number recorded last year. The lower count, as reported by satellite imagery, can also be due to increased cloud cover which hinders spotting of fires by satellites. It correlates well with the lower pollution level in Delhi-NCR. Distinct trends are emerging over the years. The number of days with severe concentration of PM2.5 has declined and duration of smog episodes are shorter, as is evident during the 2020-21 winter. Moreover, pollution hotspots are showing more volatile trends with some recording higher PM2.5 levels compared to the city as a whole and the regional averages even during monsoons,” says Avikal Somvanshi, programme manager at the Urban Data Analytic Lab at CSE. “This winter we may get a much severe peak in smog, as farm stubble fire counts may get more concentrated due to the delayed effect of the rains – to counter this, action must be scaled up right away.” Distinct trends are emerging over the years. The number of days with severe concentration of PM2.5 has declined and duration of smog episodes are shorter, as is evident during the 2020-21 winter.. Avikal Somvanshi, Programme Manager, Urban Data Analytic Lab, CSE In 2020, during the stubble burning season October 1-November 29, an average 12.2 per cent per day of Delhi’s PM2.5 pollution came from farm stubble fire smoke. This was considerably higher than previous years – in 2019, contributions stood at 8.9 per cent per day, while it was 10.9 per cent per day in 2018. On an average, while the 2020-21 winter season was 5 per cent worse in major NCR cities and Delhi compared to the 2019-20 season, the peak pollution was 13 per cent lower. Some of it can be misleading. In 2019-20 for example, even though the average level during the winter was less than in other winters, the peak daily pollution was considerably higher across all major NCR cities. This was due to the September-October rains that pushed and concentrated the farm stubble burning towards the end of October and start of November.