Global trajectories for urban passenger transport decarbonisation: a policy-based modelling approach

Abstract Understanding the impact of public policy measures on urban transport outcomes is essential for the development of evidence-based transport decarbonisation strategies. This paper presents a modelling framework to estimate the evolution of urban passenger travel and related social externalities for each of the 9234 urban areas in the world. It builds on a hybrid four-step model and systems dynamic modelling approach considering socio-economic projections and forecasts of urban growth, transport supply provision and policy assumptions to estimate transport outcomes for 19 world regions. As a result of its detailed representation of 18 transport modes and 20 policy measures, the model can be used to identify effective levers for reducing carbon emissions while improving urban public health, safety, and access to opportunities. An Increased Ambition policy scenario explores the impact of greater climate ambition on global carbon emissions from transport and other transport externalities relative to the status quo.