Intersections of Jane Jacobs' Conditions for Diversity and Low-Carbon Urban Systems: A Look at Four Global Cities

Countless cities are rapidly developing across the globe, pressing the need for clear urban-planning and design recommendations geared toward sustainability. This paper examines the intersections of Jane Jacobs' four conditions for diversity with low-carbon and low-energy-use urban systems in four cities around the world: Lyon (France), Chicago (Illinois), Kolkata (India), and Singapore City (Singapore). After reviewing Jacobs' four conditions for diversity, the four cities are introduced and their historical development context is described. A framework to study the cities along the following three dimensions is then presented: population and density, infrastructure development/use, and climate and landscape. These cities differ in many respects and their analysis is instructive for many other cities around the globe. Jacobs' conditions are present in all of them, manifested in different ways and to varying degrees. Overall, the study results show that the adoption of Jacobs' conditions seems to align well with concepts of low-carbon urban systems, with their focus on walkability, transit-oriented design, and more efficient land use (i.e., smaller unit sizes). Transportation-sector emissions seem to demonstrate a stronger influence from the presence of Jacobs' conditions, whereas the link was less pronounced in the building sector. Kolkata, a low-income, developing world city, seems to possess many of Jacobs' conditions, while exhibiting low per-capita emissions-maintaining both of these during its economic expansion will take careful consideration. Greenhouse-gas mitigation, however, is inherently an in situ problem and the first task must therefore be to gain local knowledge of an area before developing strategies to lower its carbon footprint. (C) 2015 American Society of Civil Engineers.