Pollution worsens in Capital as wind speed slows down
The deterioration was expected but comes at a time when a key anti-pollution measure – the odd-even car use curbs – is no longer in force and schools have been reopened.Updated: Nov 21, 2019 05:25 IST
Levels of air pollution began inching back up again on Wednesday, re-entering the “very poor” category as smoke from farm fires from Punjab and Haryana drifted back in and winds speed dropped, a set of exacerbating factors that is likely to persist and potentially push the air quality into “severe” levels by Friday.
The deterioration was expected but comes at a time when a key anti-pollution measure – the odd-even car use curbs – is no longer in force and schools have been reopened. The conditions, however, are unlikely to hit the extreme levels they had in two spells earlier this month.
“We are closely monitoring the situation and may review measures on Thursday. Air quality is expected to plunge to higher end of very poor or may even touch severe for a host of unfavourable conditions and higher share of stubble burning,” said a senior Central Pollution Control Board (CPCB) official, who asked not to be named.
The air quality in the national capital on Wednesday was at 301, according to the 4pm bulletin. The figure was 366 for Ghaziabad, 320 for Noida and 221 for Gurugram. By 11pm, the Delhi AQI climbed to 329.
On Wednesday, a parliamentary standing committee meeting -- previously aborted due to low attendance -- met to take stock of the measures taken and possible options for reducing air pollution.
According to lawmakers present in the meeting, the Centre told the panel that it wants to convert all commercial vehicles to CNG in future, replace thermal-based plants by gas-based plants and not allow industries in specified areas.
The officials said that out of ₹300 crore given for pollution control, ₹146 crore had already been released for Delhi.
Panel chairman Jagdambika Pal, who rushed back from his constituency in UP early morning to ensure the meeting took place, said “23 MPs were present in the meeting and all agencies came to depose before the panel”.
Meanwhile, a discussion on pollution went on in Lok Sabha for the second straight day, and is likely to conclude on Thursday. During the debate, the Congress accused the governments at the Centre and in Delhi of turning the national capital from the “greenest” to “most polluted in the world” in the last five years, with former Delhi Congress president Arvinder Singh Lovely alleging that the crisis was due to the inability of the Kejriwal government to scale up public transportation in the city.
The Supreme Court-mandated Environment Pollution (Prevention and Control) Authority had earlier this week warned Delhi’s air quality may deteriorate to “severe” zone on November 21-22 because of unfavourable weather conditions and a higher share of pollutants from crop stubble burning in neighbouring states.
According to experts, the deterioration defies usual trends – when the air quality begins improving by the third week of November – and is caused because of a long-drawn monsoon that has delayed the harvesting of paddy.
“This year because of prolonged monsoon, the (crop) stubble burning activities is still intensive. The stubble burning usually subsides completely by November 20 and all that Delhi faces is emissions from local sources. This time the continuing burning activities were made worse by the low wind speed,” Sharma said.
An analysis of pollution data published by HT on Wednesday showed that farm fires can potentially push pollution into severe zone.
An AQI between 201 and 300 is considered “poor”, 301-400 “very poor” and 401-500 “severe”, with the last category dangerous for the health of vulnerable people such as children and the elderly.
According to scientists at the India Meteorological Department (IMD), this November, Delhi has already seen three Western Disturbances and a fourth one is approaching on November 23. All the three WDs so far were weak and brought clouds but only scant rain, which in turn trapped pollutants.
“Usually there are two to three WDs that hit Delhi during this month. However, this year, we are already looking at the fourth such activity. The past activities were not strong enough to induce rain that could have washed pollutants. The cloud cover barred sunlight and winds slowed down, said, Kuldeep Srivastava, head, regional weather forecasting centre (RWFC), IMD.
The fourth activity, Srivastava said, is likely to be intense and rainfall is likely on November 26. Also, wind speed is likely to pick up to 20-25kmph on November 24-25.
The minimum temperature recorded in the early hours of Wednesday was 11.4°C.