“We evaluate car dependency by focusing on "car mode share" — the percentage of journeys made by car as opposed to other modes of transport. Using the Mobility in Cities Database (MCD) from the International Association of Public Transport, we examined how urban density, public transport availability, fuel prices, car ownership and active travel (walking and cycling) influence car use. The research, which spans metropolitan areas across Europe, the Americas, Asia, Africa and Oceania, marks a significant contribution to comparative urban studies.” Saeidizand says.

“Our key findings include four main factors determining car dependency. First is urban density: metropolitan areas with higher urban density tend to have lower car dependency. Compact cities offer shorter travel distances and better accessibility to alternative transport options. Second is public transport: both the supply and demand for public transport are crucial factors. Cities with more extensive public transport networks and higher ridership demonstrate lower car dependency. Third: fuel prices and car ownership. Fuel prices play a significant role in shaping car use. Higher fuel costs can deter car use, while car ownership rates alone do not always correlate with actual car use. Some cities, like those in Germany, have high car ownership but still rely heavily on public transport. Finally, the availability and convenience of walking and cycling infrastructure also reduce reliance on cars, offering residents viable alternatives for daily travel.” Saeidizand explains.

To reduce car dependency, policy makers can thus focus on sustainable urban development by encouraging high-density urban forms to reduce travel distances, invest in more efficient and accessible public transport systems, adjust fuel prices as a means of controlling car use, moderate car ownership and promote walking and cycling as accessible, environmentally friendly alternatives to driving.

“While this study offers a robust quantitative analysis, more research is needed on the impact of some other pivotal factors such as socio-economics, attitudes and habits related to car use. These are harder to quantify but likely also play an important role in shaping travel behaviors and the level of car dependency.” Saeidizand concludes.

Reference:

Saeidizand, P., & Boussauw, K. (2024). Patterns of car dependency of metropolitan areas worldwide: Learning from the outliers. International Journal of Sustainable Transportation, 18(3), 221–235. https://doi.org/10.1080/15568318.2023.2283462

Saeidizand, P., Fransen, K., Boussauw, K.
(2022) Revisiting car dependency: A worldwide analysis of car travel in global metropolitan areas,
Cities, 120, 103467 https://doi.org/10.1016/j.cities.2021.103467.

Contact:
Dr. Pedram Saeidizand: pedram.saeidizand@vub.be