3. Urban Planning Research in the Climate Change Era: Transdisciplinary Approach Toward Sustainable Cities

This article discusses the direction of urban planning policies toward sustainable cities. Sustainable development goals (SDGs) adopted by United Nations General Assembly range from poverty eradication, improvements in education to protection of global assets including oceans and climates. Achieving these wide ranging goals requires holistic and transdisciplinary approaches. Urban planning is one of the effective measures for SDGs because those goals are closely related with the urban activities. In this article, we first summarize a conceptual framework of the interaction between urbanization and climate change, and forecast the prospective trajectory of rapid global urbanization in this century and the consequent sustainability problems. Then, we discuss the direction of urban planning analysis to tackle the sustainability problems as sustainable science, and propose the cross-assessment approach for vision-led urban planning. The cross-assessment approach aims to explore synergistic solutions combining different value systems by assessing the impacts on a range of outcome indices of measures pursuing each value factor. The case studies for the cross assessment are taken from Japanese public transport policies. Finally, we discuss the impacts on urban expansion from socioeconomic changes and technological progress, especially in the fields of transport, construction, and communication.