Overestimated environmental benefits of short-term changes in mobility behaviour: The case of Berlin during COVID-19

Abstract

The COVID-19 pandemic changed urban mobility patterns in unprecedented ways with movement decreasing, few public transport customers, and empty streets turning into pop-up bike lanes. Accordingly, a decrease in local air pollution was reported at the start of the pandemic and models suggested a lower carbon footprint of urban mobility. Here, we offer a critical discussion of the indirect environmental impacts that can be inferred from short-lived mobility behaviour. Examining Berlin, we analyse to what extent transport volume and modal split influenced direct and indirect greenhouse gas emissions throughout the pandemic (2020–2022). The analysis combines traffic counts and survey data with process-specific life cycle assessment factors. The results show that reductions in the carbon footprint of mobility during the pandemic stem largely from a short-term decline in car use, while the modal split became more carbon intensive. Emission reductions from lower use of public transport were not realised, nor a reduction of indirect emissions from vehicle production due to slowly responding upstream demand and public transport planning. This highlights the need to revise the current assumption of perfectly responding markets in environmental footprint assessment of short-term behavioural change during crises, urban experimentation, and transitions.