Coronavirus lockdowns have played a role in causing pollution levels to drop significantly across Europe over the past month, the European Space Agency (ESA) has said.
Nitrogen dioxide levels are down around 50% in some cities, the agency said on Thursday, noting that the fall coincides with the “strict quarantine measures implemented across Europe."
The improvements in air quality were particularly clear in France, Spain and Italy, all of which have had severe lockdowns in place for several weeks.
Paris saw a dramatic drop of 54% in nitrogen dioxide concentrations when comparing the period April 13 to March 13 to the same time in 2019.
Madrid, Milan and Rome all saw decreases of around 45%.
Nitrogen dioxide concentrations vary widely day to day owing to the fluctuations of emissions, as well as variations in weather conditions, the agency also said, admitting there is a “weather-induced variability,” which makes it difficult to “draw conclusions based only on daily or weekly measurements."