The surprising effects of the coronavirus: Images of cities that now breathe pollution-free

The current air quality in most of the world's most polluted cities was unimaginable just a few months ago.
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Since the spread of the novel coronavirus COVID-19 evolved into a global pandemic, every day brings painful news about the consequences to health and the economy in the majority of countries across the planet.

However, in the midst of so many difficulties, and some exemplary lessons, social networks are capturing the only symbolic—and not so symbolic—reprieve in the crisis; the current air quality in most of the world's most polluted cities was unimaginable just a few months ago.


The other side of the coronavirus: pollution-free Himalayas re-emerge in plain sight

For the first time in 30 years, residents of Northern India gaze out of their windows in awe at the sight of the Himalayas, normally obscured by pollution.

India typically exceeds more than five times the World Health Organization safe air quality limits. According to India's Central Pollution Control Board, however, since the end of 24 March, there had been a significant reduction in air pollution. The capital, New Delhi, the most polluted city in the world, has in recent weeks boasted its cleanest air in decades.


It seems that the lack of cars on some of the most congested roads in the world is one of the reasons why air quality, in many parts of the world, has improved so significantly.


Bangkok, from closing schools due to pollution to a drastic reduction in emissions

Bangkok, the capital of Thailand, serves as another example based on the data and pictures from disbelieving pedestrians. The city has also experienced an improvement in air quality since mobility restrictions were introduced to prevent the spread of the new coronavirus. This is especially surprising since, just a few months ago, Thai authorities had ordered 437 schools in the capital's metropolitan area to close due to the unhealthy level of pollution in the air being breathed by inhabitants.


The drop in pollution related whit COVID9in recent weeks in many cities and the improved air quality is a trend that can be seen worldwide. Every country has imposed different national measures to address the coronavirus pandemic, but the drop in traffic and the most polluting industrial activities is allowing pollution to be replaced by cleaner skies in places such as Bogotá, Sao Paulo and Cali, giving us the opportunity to revisit the debate on transport methods that should be prioritised when the crisis is over.

In U.S.A., we see examples like Los Angeles, with a drop in emissions of 31%. In Europe, the European Space Agency (ESA) is collating satellite images with findings similar to those in the cities mentioned earlier, showing that, between 13 March and 13 April, nitrogen dioxide (NO2) concentrations fell by 48 % in Madrid, 47 % in Milan, 49 % in Rome and as much as 54 % in Paris, compared with the same period in 2019. Venice also exhibits its water much more transparent. However, ESA is cautious and argues that somewhat longer observation periods are needed in order to draw decisive conclusions.


Is COVID-19 more serious due to air pollution?

Researchers around the world are trying to conclude whether the mortality of COVID-19 or the severity of its consequences in many patients may be in some way related to air pollution and to the quality of the air that we breathe, or in other words, whether higher levels of pollution result in higher mortality from the disease.

At Aarhus University, environmental scientist Dario Caro, along with two health researchers at the University of Siena, Professor Bruno Frediani and Dr Edoardo Conticini, have recently published an article on the extent of the damage COVID-19 is causing in Italy. Based on the data collected, they conclude that the population of the northern regions lives in a higher level of air pollution, which can lead to more complications for patients affected by the new coronavirus due to their accumulated exposure to air pollution when they contract the disease.

Although experts will need more time to make definitive claims that COVID-19 is aggravated by pollution, another study by Harvard University, with data from over 3,000 counties in the United States, concludes that long-term pollution exposure affects the respiratory and cardiovascular systems, which can lead to increased severity of symptoms when the new virus is contracted.

Sources: Standard, La Vanguardia, Grist, The Guardian, El Periódico, EFEVerde, La Voz de Galicia