With most cities in Europe being in a lockdown so as to contain the Wuhan Coronavirus, air pollution is falling significantly in urban areas across Europe, shows new satellite images on Monday.
Cities including Paris, Brussels, Frankfurt, Milan and Madrid have shown a reduction in average levels of noxious nitrogen dioxide from March 5 to March 25, compared with the same period last year, according to the Sentinel-5 satellite images.
The new images, released by the European Space Agency (ESA) and analyzed by European Public Health Alliance (EPHA), a non-profit organisation, show the changing density of nitrogen dioxide, which can cause respiratory problems including cancer, like heat maps.
Since daily weather events can influence atmospheric pollution, the satellite pictures took a 20-day average and excluded readings where cloud cover reduced the quality of the data.
Data from the European Environment Agency (EEA) also showed a similar trend over the March 16 to March 22 period.
Average nitrogen dioxide levels in Madrid decreased by 56% week-on-week following a non-essential travel ban imposed by the Spanish government on March 14.
In a statement, the EPHA said, those living in polluted cities are likely to be at a greater risk from the COVID-19 disease, since prolonged exposure to bad air will weaken the immune system and make it harder for the body to fight the Wuhan Coronavirus infection.
“That connection is very likely,” said Zoltan Massay-Kosubek, policy manager for clean air at EPHA. “But because the disease is new, it still has to be demonstrated.”
Air pollution is known to cause or exacerbate lung cancer, pulmonary disease and strokes.
However, in some regions of Poland, nitrogen dioxide levels continued to remain relatively high during the period of the lockdown; this could be because of the prevalence of coal-based heating.
“Countries that went into lockdown later – such as Britain, which did so on March 23 – look set for a pollution reprieve in coming weeks”, said the EPHA.