Closed businesses, meeting bans and home office – due to the current Corona crisis much less people are travelling every day compared to one or two weeks ago. Satellite data has already shown in the past that this decrease in individual mobility has an impact on air quality levels.

Now we were able to verify these satellite readings in Hamburg with our ground-based air quality sensors. Since the “Kontaktverbot” (contact ban) was announced on the evening of 21 March, we are observing significant improvements of urban air quality levels in parts of the city of Hamburg. We have visualised this in the graphic below on the example of nitrogen dioxide (NO2).

Nitrogen dioxide concentration in Hamburg during the Corona crisis
Nitrogen dioxide concentration in parts of Hamburg (Holstenstraße, Platz der Republik (Altona), St. Pauli Fischmarkt, Stresemannstraße (Bahrenfeld)) during the Corona crisis

However, it is important to state that this development can not yet be observed in the whole of the city of Hamburg. There are still many air quality monitoring sites without significant changes of pollution levels, including the municipal monitoring stations.