Why Mumbai is recording more poor air quality days

Mumbai, earlier known for its coastal breeze and cleaner air, now faces a gradual annual decline in air quality, which has mirrored the old-age air pollution problem of Delhi, our national capital. The sea breezes, which helped protect Mumbai's air quality and were once considered a geographical advantage, have failed to do so now. The coastal winds were responsible for dispersing harmful particles in the city's air.

Wind patterns are critical for the quality of air. The city’s coastal nature has been an advantage despite the similar pollutant emissions as Delhi. The winds alternated between sea-to-land and land-to-sea movements, helping in natural cleaning. Nevertheless, disturbances in this cycle have greatly affected air quality. The phenomenon known as La Nina, where the ocean surface cools and wind patterns are altered, contributed greatly to high particulate matter levels in Mumbai. It delayed the expected strong wind reversal from the sea that would have otherwise removed pollutants from the lower atmosphere.

Meteorological factors are not the only cause of poor air quality in Mumbai. Some local issues have also contributed towards that situation. Currently, the air of the city has thousands of construction sites where dust particles are released into the air. There are also domestic sources that contribute to air degradation. These consist of unclean oils used in restaurants for cooking and so on.