Mumbai: Cyclone Nisarga and the accompanying rain seems to have come as a breath of fresh air for Mumbai, as for the second consecutive day, Mumbaikars breathed the cleanest air, whose quality fell in the ‘good’ category on Thursday. In less than 24 hours, the city had a hitherto unheard air quality index (AQI) of 17, the best reading for this year so far, according to the System of Air Quality Weather Forecasting and Research (SAFAR).
“Cyclone Nisarga, which battered parts of the state, bringing high-speed winds on Thursday, dispersed pollutants and combined with intermittent showers, it cleared the air,” said an expert. On Wednesday, too, the AQI was a salubrious 22, falling in the 'good' category, the second lowest AQI recorded this year so far. For Friday, an AQI of 24 is predicted. Prior to Wednesday, the lowest AQI recorded was 25, on May 23. “This is the best record of the year till now. It is due to the combination of high-speed winds and accompanying rains that the air quality index (AQI) has improved,” said Gufran Beig, director, SAFAR.
“The cleanest air day so far, since SAFAR began air quality monitoring on September 4, 2019, at 12,” he added. Mazgaon had the cleanest air in the city with an AQI of eight, followed by Colaba (12), Bhandup (15) and Malad (24). However, Worli, Andheri and Borivli recorded 35, 34 and 31, respectively, which were the highest but still 'good' AQI values. An AQI between 0 and 50 is 'good', 51 to 100 'satisfactory' and 101 to 200 'moderate'. An AQI between 201 and 300 is considered 'poor', 301 to 400 'very poor' and 401 to 500 'severe', while an AQI value over 500 is 'severe plus'. A day after Cyclone Nisarga passed over Mumbai, heavy showers and strong winds lashed the city on Thursday morning.
“Cyclone Nisarga, which spared Mumbai, making landfall in adjoining Alibaug on Wednesday, is now a depression over west Vidarbha region in Maharashtra and will weaken further,” said an official from the IMD. The IMD officials said they were expecting more rain, including some heavy showers, since Mumbai was witnessing a combination of the postcyclone effect and monsoon winds over the west coast. When a cyclone passes, it leaves a lot of moisture over land. Relative humidity levels at 8.30am stood at 92 and 87 per cent, at Colaba and Santacruz respectively.
“When such a huge weather system (cyclone) passes, it leaves behind a remnant effect in the form of very high humidity levels and moisture content over the entire coast, including Mumbai, Thane and Raigad. In addition, there are strong westerlies coming over Mumbai and the entire west coast, since the Indian summer monsoon season has begun, pumping in a lot of moisture “ said KS Hosalikar, IMD’s deputy director general for Mumbai region.
