Urban environmental transitions and urban transportation systems - A comparison of the North American and Asian experiences

This article argues that the urban environmental transition as experienced by rapidly developing Asian cities is significantly different from that experienced by the West. Urban environmental transition theory suggests that cities undergo a series of environmental challenges as they develop. At first, the priority environmental challenges are those relating to the 'brown' agenda, including water supply, sewage and sanitation issues. As cities industrialise they are confronted by 'grey' agenda challenges or those associated with industrial and auto-related pollution. Cities in post-industrial societies are battling 'green' agenda challenges such as greenhouse gas emissions, ozone-depleting substances, non-point-source pollution and increasing volumes of municipal waste. This shift in type of impact is accompanied by a shift in scale (from local to global), timing (from immediate impacts to those that are delayed), and character (from health-threatening to ecosystem-threatening). While cities of the West have experienced these impacts in a sequential order, with one set sometimes emerging from the 'solutions' to the previous set, cities in rapidly developing Asia are experiencing a different, compressed form of the transition. The authors compare the development of urban transportation systems with other challenges to demonstrate this difference. This compressed urban environmental transition, in which challenges must be met within shorter timescales, also presents the problem of overlapping or telescoped sets of transition challenges.