JOIN USThe pollution levels in Delhi this winter have worsened compared to last year, according to an analysis by Centre for Science and Environment (CSE).
Both November and December 2015 show highest number of days in ‘severe’ category, the worst category according to the National Air Quality Index.
December 2014 had at least three per cent of days in ‘good’ and ‘satisfactory’ category.
But December 2015 had none, the analysis of the official air quality data from the continuous monitoring by Delhi Pollution Control Committee (DPCC) says.
November 2015 had 73 per cent of days in ‘severe’ category against 53 per cent in November 2014.
Similarly, December 2015 has 67 per cent of days in ‘severe’ category as against 65 per cent in December 2014.
There has not been a single ‘good’ air quality day this winter, the CSE said.
“If globally, smog episode is defined as three consecutive days in the worst category of the Air Quality Index, then the 2015 winter has already witnessed 11 such smog episodes. Such levels have lasted for 10 consecutive days as well.
“This justifies emergency action like the odd and even system that Delhi should pilot successfully to reduce toxic exposure during smog episodes,” it said.
Second largest emitters
It said that the Kanpur IIT study has shown that in winter, vehicles are the second largest emitters of PM 2.5 after road dust.
“Moreover, in different parts of Delhi, diesel four-wheelers are the source of at least 60-70 per cent of PM2.5 in winter. Several other studies in Delhi have shown how real-time exposure on roads and close to roadside is several times higher than the background ambient levels,” CSE said in a statement.
Quoting a study by the scientists of University of California, Berkeley, which has shown that in Delhi people’s exposure to vehicle exhaust is three to four times higher than the world average, it urged the government that the odd and even number system is
enforced with stringency to help develop alternative commuting practices and systems that can be sustained on a long-term basis.
“Given the level of choking pollution in the city and its health impact, people need to support to reduce their pollution foot print. Despite the exemptions granted to two-wheelers and women, voluntary participation is critical to reduce public health risk in the city,” it said.