Environmental, economic, and health co-benefits of a shift away from motor vehicles in London - Presenting a simplified modelling framework for preliminary screening of urban transport interventions

Abstract

Background and Aim: Cities contribute to 75% of global greenhouse gas emissions, accelerating climate change and significantly impacting public health. Rapidly rising rates of urbanization and population growth are emphasizing these effects. This presentation investigates how co-benefits can be generated when redesigning cities to reduce car-reliance. It makes the case for a system-thinking approach that can leverage intersectoral relationships, exploit synergistic effects, and maximize health co-benefits of climate change strategies. It aims to bridge the gap between research and policy by offering an open-source framework that can quantify the co-benefits of traffic reductions in Europe. Methods: A suite of publicly available models was assembled into a unified framework to quantify health benefits of car reduction strategies in cities. These include: SHERPA and SHERPA-City to simulate impacts on NO₂ and PM₂.₅; AirQ+ to calculate the respective premature deaths prevented; HEAT to estimate health benefits from physical activity stemming from traffic re-allocated to active travel; UTOPHIA methodology to assess benefits of noise reduction and green space improvements. Lastly, statistical analysis is used to highlight how system-thinking can be economically advantageous. The framework was applied to hypothetical scenarios in London. Results: For a reduction in traffic between 10 and 50%, annual mortality was impacted by changes in physical activity (169 to 878 deaths prevented), NO₂ (45 to 227 deaths prevented), PM₂.₅ (7 to 52 deaths prevented), noise (34 to 167 deaths prevented), and green space (20 to 97 deaths prevented). Conclusion: The results were in accordance with published literature, revealing co-benefits of modifying travel habits are substantial and attractive to multiple stakeholders. Physical activity from active transport was found to be particularly beneficial and should therefore be the focus of urban mobility interventions, proving to be greener, healthier, and more equitable than shifting to a carbon-neutral fleet. Keywords: Co-benefits, climate change, active transport