Felix Creutzig & Steffen Lohrey, Mercator Research Institute on Global Commons and Climate Change, Berlin, Germany
Presentation Title: Urban form and the environment
With global environmental change and the rise of global megacities, environmental and social externalities have become increasingly prevalent in determining optimal urban form. There are specific effects on climate change (transport and residential energy use), air pollution, congestion and land rent burden. This presentation described trade-off curves between these externalities and identified individual utilities. Denser urban forms would mitigate climate change, but would increase the land rent burden on citizens. A denser urban form might, however, translate into increased air pollution. But, if higher transport costs for individual transport are combined with easy accessibility for public transport and cycling, air quality could also be improved in dense cities. These results reveal a 'sustainability window' where only a combination of transportation policies, infrastructure investment and progressive public finance simultaneously enables the development of cities and sustainability dimensions. Modal choice, technologies and land rent policies can modify the trade-off curves, better co-aligning urban welfare with beneficial global environmental change.
Key Lessons Learned
- Denser cities can contribute to climate change mitigation, but can also have a high impact on air pollution. Public transportation mitigate the impact of air pollution, but can also have an impact on cost of living.
- 50 people per hectare is an appropriate population density, in order to achieve a high level in all dimensions of urban sustainability.