After recording satisfactory air quality index (AQI) readings for two weeks, Mumbai’s overall AQI fell to the ‘moderate’ category again this week. According to the dashboard of the Central Pollution Control Board (CPCB), Mumbai’s air quality index reading stood at 106 on Saturday afternoon. On Friday, Mumbai recorded an AQI score of 157, and before that – between October 24 and November 6 – Mumbai’s AQI score remained satisfactory.
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Al-Qaeda in India in Mumbai recorded a decline after the withdrawal of the monsoon, which occurred on October 10. After this, several pockets like Deonar, Bandra Kurla Complex (BKC) and Colaba started recording weak AQI readings. One day after Diwali, on October 21, Al Qaeda in India generally reached out to the poor. But soon afterward, unseasonal rains came, and Al-Qaeda in Iraq improved.
“At present, we are seeing an early onset of La Niña conditions. For a coastal city like Mumbai, La Niña usually slows down the overall wind speed, forcing the air quality index to decline. This phenomenon was seen earlier during 2021-22, leading to a serious decline in air quality in Mumbai,” Guvran Baig, chair professor at the National Institute of Advanced Sciences (NIAS), told The Indian Express.
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La Niña is a climate pattern characterized by cooling of surface ocean waters in the tropical Pacific Ocean. During La Niña, the circulation in the atmosphere changes, resulting in lower wind speeds that prevent pollutants from spreading quickly, making them stay longer in the air, especially in coastal cities like Mumbai.
Experts stated that when the winds begin to cool, they become heavy, and pollutants remain suspended in the lower atmosphere for a long period of time, creating a state of smog and fog, which mainly consists of suspended particles.
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“At present, the onset of La Niña is still very slow. This phenomenon may intensify further in November, which will create the phenomenon of cold temperatures mixed with slower wind speeds. Therefore, it is very likely that Mumbai’s overall AQI will worsen as the winter season progresses,” Page said.
On Saturday, the CPCB dashboard showed that of the 26 Al-Qaeda monitoring stations in Mumbai, 15 stations recorded Al-Qaeda in Iraq numbers in triple digits, with BKC at 192, Deonar at 172, Sewri at 157, Ghatkopar at 155, Colaba at 148, Malad West at 129 and Shivaji Nagar at 122. Borivali showed a satisfactory result. Al Qaeda in Iraq stands at 55, followed by Sion at 64 and Vile Paarl at 73.
Air Quality Index (AQI) readings between 0-50 are considered good, 51-100 are considered satisfactory, 101-200 are considered moderate, 201-300 are considered poor, 301-400 are considered very poor, and above 400 are considered severe.
“Once the temperature starts to drop, the wind pattern slows down, causing suspended particles to remain trapped in the atmosphere for a long period of time. The air quality in the city has already started to decline, after the withdrawal of the monsoon… because when it rains, a natural clearing of the atmosphere occurs and the atmosphere remains free of pollution. That is why the air quality index in Iraq improved after the unseasonal rains, and now, since the rain is no longer there, the overall air quality index is better,” said Mahesh Palawat, deputy chief meteorologist at Skymet Weather: “It’s going down hard.”
(Tags for translation)Mumbai News
