New Delhi, November 12 (Language) On Sunday, the day of Diwali, the air quality of the national capital was recorded the best in eight years. However, burning of crackers and low temperatures at night may increase pollution levels.
Delhiites woke up to a clear, sunny morning with the city’s air quality index (AQI) at 218 at 4 pm, the best in at least three weeks.
AQI between zero and 50 is ‘good’, 51 to 100 is ‘satisfactory’, 101 to 200 is ‘moderate’, 201 to 300 is ‘poor’, 301 to 400 is ‘very poor’ and 401 to 450 is ‘poor’. Is considered ‘severe’ between. When AQI exceeds 450, it is considered in the ‘very serious’ category.
According to Central Pollution Control Board data, AQI in Delhi was 312 on Diwali last year, 382 in 2021, 414 in 2020, 337 in 2019, 281 in 2018, 319 in 2017 and 431 in 2016.
The 24-hour average AQI on Saturday was 220, the lowest on a day before Diwali in the last eight years.
This time, the air quality in Delhi improved rapidly just before Diwali. The biggest reason for this is the intermittent rain on Friday and favorable wind speed to carry away the pollutants.
The 24-hour average AQI on Thursday was 437.
The air quality in the city ranged from ‘very poor’ to ‘severe’ for two weeks from October 28 and a suffocating smog engulfed the capital during this period.
The India Meteorological Department (IMD) had already predicted a slight improvement in air quality just before Diwali due to favorable weather conditions including light rain due to the influence of western disturbance.
The western disturbance brought rain to most parts of northwest India, including Punjab and Haryana, reducing the contribution of smoke from stubble burning in neighboring states to Delhi’s air pollution.
An IMD official had earlier said that once the western disturbance passes, the wind speed will increase to about 15 kilometers per hour on November 11 (Saturday), which will help in dispersion of pollutants before Diwali (November 12).
In view of the trend over the last three years, the Delhi government has announced a blanket ban on the manufacture, storage, sale and use of firecrackers within the national capital.
Sporadic incidents of burning of firecrackers were reported in the national capital on Saturday night and Sunday evening.
Pollution levels may increase in Delhi on Sunday night due to low temperature and burning of firecrackers.
In Delhi, stubble burning in neighboring states, especially Punjab and Haryana, accounted for 23 per cent of pollution in the national capital on Wednesday, according to data from the ‘Decision Support System’ that identifies sources of particulate air pollution. The smoke released was responsible. The contribution of stubble burning incidents to the pollution level in the city was 33 percent on Thursday, while it was 10 percent on Friday.
In the data, transport has also been cited as the main cause of air pollution, which is contributing 12 to 14 percent to the deteriorating air quality of Delhi.
Vinay Kumar Sehgal, principal scientist at the Indian Agricultural Research Institute in New Delhi, predicted that incidents of stubble burning will reduce in Punjab and Haryana around Diwali due to humid conditions after the rains.
Delhi Environment Minister Gopal Rai on Friday said the government has postponed the odd-even car scheme for the time being as the city’s air quality has improved significantly due to the rains.
He told the press conference that the government will review the air quality after Diwali and if pollution levels rise too much, a decision on the odd-even scheme can be taken.
Rai had earlier said that the scheme would be implemented in the city after the Supreme Court reviews the effectiveness of the odd-even car scheme and issues its order.
On Tuesday, the apex court had questioned the effectiveness of the Delhi government’s odd-even scheme and termed it a ‘sham’.
Doctors have said that breathing Delhi’s polluted air is equivalent to the harmful side effects of smoking 10 cigarettes a day.
All the strict restrictions required under the final phase of the Central Government’s ‘Gradual Response Action Plan’ (GRAP) to tackle air pollution in Delhi-NCR have also been implemented in the national capital.
According to analysis by the Delhi Pollution Control Committee (DPCC), pollution levels in the city peak from November 1 to 15, as incidents of stubble burning increase in Punjab and Haryana during this time.
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