Lock-in Effects of Road Expansion on CO2 Emissions : Results from a Core-Periphery Model of Beijing

In the urban planning literature, it is
frequently explicitly asserted or strongly implied that
ongoing urban sprawl and decentralization can lead to
development patterns that are unsustainable in the long run.
One manifestation of such an outcome is that if extensive
road investments occur, urban sprawl and decentralization
are advanced and locked-in, making subsequent investments in
public transit less effective in reducing vehicle kilometers
traveled by car, gasoline use and carbon dioxide emissions.
Using a simple core-periphery model of Beijing, the authors
numerically assess this effect. The analysis confirms that
improving the transit travel time in Beijing s core would
reduce the city s overall carbon dioxide emissions, whereas
the opposite would be the case if peripheral road capacity
were expanded. This effect is robust to perturbations in the
model s calibrated parameters. In particular, the effect
persists for a wide range of assumptions about how location
choice depends on travel time and a wide range of
assumptions about other aspects of consumer preferences.