Assessing the effects of significant activity changes on urban-scale air quality across three European cities

• Published in: Atmospheric Environment: X Vol. 22; p. 100264
• Main Authors: Ramacher, Martin Otto Paul, Badeke, Ronny, Fink, Lea, Quante, Markus, Karl, Matthias, Oppo, Sonia, Lenartz, Fabian, Dury, Marie, Matthias, Volker
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2024; Elsevier
• Subjects: Activity data; Covid-19 lockdown; Emission reductions; Policy support; Urban air quality modeling; WHO AQG values; WHO AQG values; Policy support; Activity data; Covid-19 lockdown; Urban air quality modeling; Emission reductions
• ISSN: 2590-1621; 2590-1621
• DOI: 10.1016/j.aeaoa.2024.100264

This study investigates the effects of significant activity changes on air pollutant concentrations across the three European cities Hamburg, Liège, and Marseille and focuses on the effects of COVID-19 lockdown measures as a case study for such significant activity changes. To identify such effects, this study utilizes urban-scale chemistry transport modeling, embedded in regional-scale Chemistry Transport simulations. The outcomes underscore the significance of considering local conditions and emissions sources, as variations between urban and regional simulations demonstrate. Notably, lockdown regulations yield the most substantial impact in Marseille due to its dense road traffic and port area, with Liège following suit, primarily influenced by regional air quality alterations. Conversely, Hamburg exhibits lower mean changes, attributed to its widespread urban structure. Analysis of modeled exceedances of limit values reveals significant reductions, particularly in areas of urban and road land use. These findings contribute valuable insights into the efficacy of significant activity changes, such as lockdown measures, in mitigating air pollution, underlining the importance of tailored strategies for emission reduction in urban environments. •Activity changes have strong influence on emissions and air quality.•Traffic emission changes can be assessed from mobility data.•Urban scale CTMs show higher lockdown impacts than regional models in urban areas.•Effects of lockdown emission changes on air quality varies strongly from city to city.