Delhi has been topping WHO’s list of the world’s most polluted megacities, earning it global notoriety. So, it comes as a surprise that in the last two weeks, Mumbai witnessed far higher air pollution levels than the national capital.
For over two weeks, Delhi did not witness a single high pollution day. In Mumbai, on the other hand, pollution levels were way above the permissible limits, according to a study by the System of Air Quality Weather Forecasting and Research (SAFAR).
What’s important is that this change is not because of increased pollution in Mumbai, but thanks to a considerable improvement in Delhi’s air quality, scientists said.
The study, conducted between 27 February 2017 and 13 March 2017, assessed the air quality in the two cities as well as in Pune. Mumbai had 20% ‘very poor’ air days, while Delhi and Pune had none. In fact, Mumbai saw only 13% ‘satisfactory’ air quality days. Delhi and Pune had 40% and 47% respectively.
Speaking with Hindustan Times, SAFAR Director Gufran Beig said that a landlocked city like Delhi is usually more prone to pollutants getting trapped closer to the surface due to unfavourable weather conditions. But recently, high-speed winds and intermittent rain helped clean up the city’s air.
Mumbai has the advantage of having a sea breeze, but that did not play a crucial role in dispersing pollutants as wind speed was less during most days between February and March.Gufran Beig, SAFAR Director