Winds help improve index, but Capital’s air stays very polluted

Delhi recorded an average AQI of 330 in the very poor category, down from 437 (severe) recorded on Saturday. According to the CPCB data, AQI on seven of the first 14 days in November was in the severe zone

The smoke grey skies over Delhi opened up a little on Sunday with long-range transport level winds that bring stubble emissions slowing down, pushing the air quality back into very poor zone from the severe recorded on Saturday, even as the city registered the season’s coldest morning at 10.1 degrees Celsius.

Doctors have warned that even short-term exposure to such polluted air may cause irreversible damage to critical organs of even healthy individuals. (Parveen Kumar/HT)

Delhi recorded an average air quality index (AQI) of 330 in the very poor category, down from 437 (severe) recorded on Saturday.

The national capital is in the grip of a severe pollution episode prompting the Supreme Court on Saturday to order the central and Delhi governments to take emergent steps, including a two-day lockdown.Hours later, the Delhi government announced shutting of schools for in-person classes, a four-day ban on construction and ordered its staff to work from home for a week.

Delhi recorded an average air quality index (AQI) of 330 in the very poor category, down from 437 (severe) recorded on Saturday. According to the Centra Pollution Control Board data, the air quality on seven of the first 14 days in November was in the severe zone; it was very poor on six days and remained poor for one day.

Forecasting agencies said the share of stubble burning in Delhi’s overall air pollution mix fell to 12% on Sunday from 31% on Saturday.

Even at ‘very poor’, CPCB’s health advisory states the air quality can cause respiratory illnesses on prolonged exposure, indicating the improvement in the air quality index was only a temporary respite. Forecasts show the AQI is expected to stay in the ‘very poor’ category over the next two days, despite a slight deterioration.

“The air quality over Delhi improved to ‘very poor’ from the ‘severe’ category and is likely to remain in the ‘very poor’ category for the rest of Sunday. It will deteriorate slightly, but will remain in the ‘very poor’ category on Monday and Tuesday,” the daily bulletin issued by the Early Warning System (EWS) for Delhi said. The EWS is a part of the ministry of earth sciences’ forecasting model.

According to the EWS, wind speeds from northwest of Delhi have slowed down and were blowing at 4 km/hr on Sunday. The wind speed expected to be remain similar on Monday as well. On Tuesday, the wind speed could reach up to 8 km/hr.

The System of Air Quality and Weather Forecasting And Research (Safar) says while the number of farm fires have increased in the last 24 hours, touching 3,445 fires as compared to 3,157 on Saturday, the stubble share has reduced, owing to a reduction in transport-level winds.

While activities to prevent pollution from spiking further, such as the ban on construction activities in Delhi till November 17, kicked into action from Sunday onwards, other restrictive measures such as the ban on physical classes at schools and making government offices work from home will kick into place from Monday onwards.

Karthik Ganesan, Fellow and Director - Research Coordination at the Council on Energy, Environment and Water (CEEW) says while the new measures are welcome, the Graded Response Action Plan (GRAP) needs to be rethought.

“It must be implemented as an ex-ante emergency measure, by considering air quality forecasts and not waiting for the situation to worsen for 48 hours or longer. We have the science that gives us an indication of things to come, given how meteorology plays a significant role in the deterioration of air quality,” he said.

Dr Col Vijay Dutta, Internal Medicine & Respiratory Medicine at the Indian Spinal Injuries Centre says ‘very poor’ may be a category slightly better than ‘severe’, but its impact remains quite similar. “Pollution levels are still very high and anyone going out needs to use masks to minimize inhalation of toxic air. Any form of physical activity also needs to be avoided. Even healthy people can develop breathing, lung problems and even cancer in the long run, if there is exposure to such air,” he said.