Important sources of Nitrogen Dioxide (NO₂) in cities are from vehicle traffic, from heating and cooking in residential properties, and from power plants.The strict COVID-19 regulations lead to a reduction of road and air traffic, a temporary closing of companies, and a decrease of industrial productivity. These in consequence affect emissions of air pollutants, especially from the transport and industry sectors, which are significant sources of NOx (nitrogen oxides) in cities. With these regulations, it was hypothesised that there would be a reduction in NO₂ levels, which could be measured from space.

In this video, Kezia Lange explains the method used to find out if there was a COVID-19 lockdown effect on Nitrogen Dioxide (NO₂) levels using satellite data from Sentinel-5p, the issues that were overcome, and results for Buenos Airies, Argentina and New Delhi, India. Jieying Ding explains the results for China, followed by a summary from Bas Mijling.

‍

Featured Educators

• Dr Bas Mijling, Air Quality Scientist, KNMI
• Kezia Lange, Atmospheric Scientist/PhD Student, Universityof Bremen
• Dr Jieying Ding, Air Quality Scientist, KNMI  

Thanks to all of the contributing scientists for self-filming during the COVID-19 lockdown.