Worli Sea Link disappears in haze as AQI in Mumbai worsens

Worli is obscured by a dense blanket of smog on Friday afternoon. Pic/Ashish Raje

The city's air quality index (AQI) started dipping again on Friday, causing several areas in the city and eastern and western suburbs to experience ‘poor' air quality. Mumbai's overall average AQI, however, stood at 179 (moderate).

The AQI scale categorises air quality as ‘good' from 0-50, ‘satisfactory' from 51-100, ‘moderate' from 101-200, ‘poor' between 201-300, ‘very poor' from 301-400, and anything higher than 400 as ‘severe.' Many areas in Mumbai recorded AQI levels above 200, causing a thick blanket of haze to form over many pockets of the city. The worst AQI in the city was at Malad West (see box) followed by Borivli East and Navy Nagar in Colaba.

Posting a video of Bandra Worli Sea Link being rendered invisible due to the haze, veteran journalist and author Sucheta Dalal took to X, writing, "Breaking news! The Worli-Bandra bridge has vanished!! Yes-vanished into thick smog. But don't worry. Remain focused on Mandir-Masjid- pollution is going to reduce your lifespan by 5 years anyway! Why worry? allow netas & babus to make money! Not our concern, no?? (sic)."

Meanwhile, independent weather enthusiast Rushikesh Agre, popularly known for his social media handle ‘Mumbai Rains' on X, wrote, "Dense fog is present over Mumbai and many areas of MMR at 7 AM, AQI crosses 200+ in many areas." According to Dr Gufran Beig, chair professor at the National Institute of Advanced Sciences (NIAS), Mumbai's weather is notably dry due to low moisture content. As the temperature falls, residents have reported little to no sweating. Beig said that this reduced humidity, combined with strong horizontal and vertical air movement, also known as eddy diffusion, has led to hazy skies without a corresponding rise in ground-level AQI.

Beig elaborated, "When Mumbai's humidity is usually high, tiny particulate matter attaches to the moisture droplets suspended in the air. This causes the particles to linger at lower elevations, worsening air quality. At the moment, however, the air contains fewer moisture droplets, and both horizontal and vertical wind speeds are unusually strong. These conditions push the pollution layer higher until it encounters an inversion layer, which prevents it from rising further. As a result, the pollutant layer remains suspended below the inversion layer, creating a hazy appearance when viewed from the ground."

AQI IN CITY AND MMR (good AQI is 0-50)

Malad West (IITM station) 298
Borivli East (IITM) 279
Navy Nagar, Colaba (IITM) 269
Bhayander West (MPCB) 251
Mazagaon (IITM) 245
Kandivli West (BMC station) 233
Chembur (MPCB station) 229
Shivaji Nagar, Govandi (BMC) 228
Bolinj, Virar (MPCB) 218
Deonar (IITM) 215
Siddhivinayak Nagar, Ulhasnagar (MPCB) 212
Kalyan-Pimpleshwar Mandir (MPCB) 202