CHENNAI : How long can government officials be in denial mode about rapidly deteriorating air quality? Chennai Air Quality Index (AQI) on Friday evening crossed 300, which happens to the worst till date and it’s fifth day on the trot where Chennaites are gasping for breath.
Despite such unusual spike in air pollution, neither Tamil Nadu Pollution Control Board (TNPCB) nor the health department has issued any public advisory. The Central government’s Sameer application, which calculates AQI, has indicated that city poor air quality would have definite health impact causing respiratory illness on prolonged exposure. The continuous ambient air quality monitoring station at Manali has recorded maximum PM 2.5 concentration level of 451 µg/m3.
Meteorology not the only reason for record air pollution in city: Experts
The continuous ambient air quality monitoring station at Manali has recorded maximum PM 2.5 concentration level of 451 µg/m3 (micrograms per cubic metre), which is hazardous. For the first time, all three CPCB monitors at Velachery, Alandur and Manali have turned ‘red’ indicating ‘very poor’ air quality. At 6.30 pm, Manali AQI was 342, Alandur 301 and Velachery 307.
Meteorological impactSo far, there has not been proper explanation to what is causing such sudden rise in pollution levels. Can meteorological reasons alone be blamed?
Sarath Guttikunda, director of Urban Emissions (India), an independent research group on air pollution, told Express that pollution levels are impacted by meteorology as much as the emissions do. “If the winds are fast, then emissions will disperse away and pollution is less. If there is rain, most of the pollution in the atmosphere is scavenged and we have a clean slate. If the winds are slow or just circling in one place, then there is build up of pollution and numbers spike.”
While dismissing a notion in social media about Delhi pollution pushing towards East Coast of India, Guttikunda explains a very rare occurrence, “In the past week, we have seen strong uplift of pollution from the Indo-Gangetic plain, which travelled over to Bay of Bengal, and circled over to the mainland in South East with the help of strong winds. A small bump in the pollution levels over Chennai, for a couple of days, could be because of this aged mass of pollution from all of Indo-Gangetic plain. This is a rare occurence mostly driven by the force of cyclone ‘Bulbul’. However, at the same time, due to stagnant winds in the South, there is also a significant build up of pollution over the cities, which leads to the spike.”
Noted environmentalist Chandra Bhushan said Chennai’s pollution woes are majorly a local phenomenon. But, some pollutants interacting in upper air over North India can be pushed down south. “However, it would only be marginal. I have been saying this, pollution is no longer a problem of northern States. Government has to take measures before Chennai becomes another Delhi.”
Is pollution seasonal?
Shweta Narayanan of Healthy Energy Initiative says: “Air quality in 15 locations sampled from across the city between May and July was unhealthy, with levels of PM 2.5 in the worst affected areas nearly three times the national standard of 60 µg/m3. The widespread nature of pollution and the fact that the samples were taken in summer highlights how the current pollution crisis is neither an isolated nor a seasonal incident.”