How the virus cleared the world’s most polluted skies

As air pollution plummeted to levels unseen in living memory, people shared pictures of spotless skies and even Himalayan peaks from cities where the view had been obscured by fog for decades. On one social messaging group, a resident of the capital, Delhi, which regularly records some of the foulest air in the world, celebrated the city's "alpine weather ". Politician and author Shashi Tharoor wrote that the "blissful sight of blue skies and the joy of breathing clean air provides just the contrast to illustrate what we are doing to ourselves the rest of the time". Schools were shut, flights were diverted, and people were asked to wear masks, avoid polluted areas and keep doors and windows closed. Image copyrightHindustan TimesImage caption The financial capital Mumbai also seems very different The deadliest particle in Delhi's foul air is the tiny but deadly PM 2.5, which increases the likelihood of respiratory and cardiovascular diseases. After all, urban Indians' and the media's panic and outrage during the deadly winter pollution every year soon gets lost in the fog of summer heat and concerns over monsoon rains and droughts. "We don't yet have a democratic demand for clean air," Arunabha Ghosh, Chief Executive Officer of the Council on Energy, Environment and Water, a leading climate think tank, told me. China tried to clean up its air several times before hosting marquee international events - like the Beijing Olympics in 2008, the World Expo in Shanghai and the Guangzhou Asian Games in 2010 - before sliding back to grey, smoky skies. So could a lockdown to prevent the spread of a pandemic, which has imperilled the health and livelihoods of millions, trigger similar policy changes to clean up India's air? (Facing energy shortages after the loss of the Fukushima nuclear power plant, Japan unleashed a Cool Biz campaign to cut down air conditioning in workplaces and reduce carbon emissions by asking office workers to shed their suits.)