NEW DELHI: Despite seeing the least toxic air in the past five years, Delhi was the most polluted major city in NCR with a winter average of 160 micrograms per cubic metre (g/m³), according to a recent analysis by Centre for Science and Environment (CSE).Except R K Puram, all hotspots showed an improvement compared to the average pollution levels recorded over the previous three winters.Track the pollution level in your city”This improvement is a combined effect of meteorology and emergency action based on pollution forecasting. There was heavy and extended rainfall in the early phases of the season that prevented smog episodes from building up and also lowered the seasonal average,” said Anumita Roychowdhury, executive director, research and advocacy, CSE.She added, “Despite the decline, Delhi continues to remain the most polluted among the cities and towns of NCR. This downward trend will have to be sustained with much stronger action on vehicles, industry, waste burning, construction, solid fuel and biomass burning to meet the clean air standard.”The CSE study revealed hotspots in north and east Delhi to be the most polluted. Jahangirpuri was the ‘most polluted’ official hotspot with an October-January average PM2.5 level of 201 micrograms per cubic metre. Other most polluted hotspots were Anand Vihar (196 g/m³), Wazirpur (185 g/m³), Mundka (185 g/m³), Rohini (182 g/m³) and Bawana (179 g/m³).Bahadurgarh with 105 g/m³, and Gurgaon and Faridabad each with 133 g/m³ were the least polluted hotspots.RK Puram registered a 1% increase during October-January levels this year than the average of the previous three winters. Wazirpur (5%), Narela (3%), Mayapuri (3%) and Faridabad (3%) registered improvements, but it was less than the improvement noted in Delhi’s city-wide average.The PM2.5 level, computed by averaging monitoring data from 36 CAAQMS stations located in the city, was 17% lower compared to the seasonal average of 2018-19 winter. Based on the subset of the 10 oldest stations, there is an improvement of almost 20%.CSE researchers estimate that about 4.1 tonnes of PM2.5 fell over Delhi this winter in the form of smoke, which is 37% less than 6.4 tonnes last year and almost half of the 2020-21 winter figure.”The quantity of smoke from farm fires that falls over Delhi is dependent on two major factors: quantity and intensity of stubble fires, and meteorological conditions conducive for transportation of the smoke to the city. This winter, not only have the quantity and intensity of farm stubble fires been low, but the meteorological conditions have also been less conducive for the transport of the smoke,” said the study.The study said the total count of farm stubble fires reported this year from Punjab, Haryana and Delhi in October and November stood at 55,846, according to Nasa’s VIIRS satellite, and 12,158, according to its MODIS satellite. These are respectively 36% and 40% lower than the figures for October-January in 2021-22.
Source: https://timesofindia.indiatimes.com/city/delhi/winter-air-delhis-best-in-5-years-not-good-enough/articleshow/98463511.cms
