POLLUTION

Delhi Suffocates With ‘Severe’ Air Pollution Episodes; Witnesses Season’s First Fog as Temperatures Slide

November 05, Friday: Being a transition month, October offered a bit of all four seasons for Delhi—high daytime temperatures, intermittent rainfall, cold morning hours and a few pleasant days. However, since the start of November, mercury levels have been dropping relentlessly in the city, with daytime temperatures staying well below 30°C. Now, with the first glimpses of winter, the persistent air pollution problem has reached its zenith, with parts of the city registering ‘severe’ air quality on Thursday.

On Friday morning, the average Air Quality Index (AQI) from 37 monitoring stations across Delhi stood at a whopping 446. Mundka, Narela, Bawana, Jahangirpuri, Punjabi Bagh, and Najafgarh were the most polluted localities within the city, with hazardous levels of AQIs at 470+ at 7 am on Friday.

The Central Pollution Control Board (CPCB) and System of Air Quality Weather Forecasting and Research (SAFAR) categorises AQIs between 101-200 as ‘moderate’, 201-300 as ‘poor’, 301-400 as ‘very poor’, and those above 400 as ‘severe’.

Season’s first fog

Temperatures across Delhi-NCR have started to drop, with Delhi registering a daytime maximum of just 27.8°C on Thursday. On Friday morning, the minimum temperature touched 15°C—normal for this time of the year. A lowest of 10.4°C was recorded in Adampur in Punjab on Thursday.

On Thursday morning, Delhi witnessed the season's first fog, with both the IGI and Safdarjung Airports reporting poor visibility with a significant reduction to the range of 600-800 metres between 7 and 11 am.

People shop for Diwali in Delhi (Yogesh Kumar / BCCL, Delhi) — People shop for Diwali in Delhi
(Yogesh Kumar / BCCL, Delhi)

"This (fog spell) has been due to calm/light wind prevailed during this period and presence of higher humidity in the range of 88-95 per cent," the IMD's R.K. Jenamani said. Shallow to moderate fog is likely to prevail across the region until Saturday morning and then subside after that due to winds strengthening, says IMD.

In deep winters, fog season means less and less visibility, especially for airports, leading to the diversion of flights. On the highways, dense fog results in accidents, and therefore, motorists must maintain utmost caution.

Pollution woes

As per SAFAR, Delhi has recorded an overall AQI of 386 today, which lies towards the lower end of the ‘very poor’ category. Earlier, SAFAR forecast that Delhi’s air quality may enter the ‘severe’ category even without any firecracker emissions. If firecrackers burned even at 50% of last year, the AQI could shoot up beyond 500 on Friday morning, warned SAFAR, which operates under the Ministry of Earth Sciences. Relief is expected only from Sunday evening onwards.

Worsening of Delhi's air quality despite a complete ban on firecrackers remains a cause of concern. National Capital Region (NCR), too, fell in the same category, where there was no such ban on firecrackers. According to health experts, an AQI of such an extent may cause respiratory impact even on healthy people and serious health impacts on people with lung or heart disease.

With stubble burning share in Delhi's air pollution set to increase over the next three days, SAFAR has projected an AQI of 500 plus on Friday even if Delhiites burst 50 per cent fewer crackers than last year. The agency said that stubble share is predicted to increase to a peak of 35-40 per cent on Friday and Saturday as per sensitivity simulation, primarily due to transport-level winds reaching Delhi from the northwest.

Every year Delhi-NCR faces a drastic deterioration in air quality from October onwards. The pollution season peaks around Diwali due to unfavourable meteorological conditions, stubble burning emissions from neighbouring states and firecrackers. Continued local emissions such as construction dust, industrial and power plant pollution and vehicular emissions add to the woes for Delhi-NCR.

(With inputs from IANS)

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