What can urban design learn from changing winds? A case study of public space in Nanjing (1990s-2010s)

Abstract

Climate is one of the prominent and persistent factors affecting the human habitat. During the recent urbanization, human society has left remarkable environment footprints including the macro- and micro- climates related to human settlement. It’s essential for urban planning decision-maker to contextualize people’s wellbeing in the public space and micro-climate changes. The adverse changes of micro-climate are usually related more to local developments than to global changes, with the causality relatively feasible to detect. Characteristic of openness, the open spaces play an important role as outdoor relaxation and wind corridor, which is precious yet vulnerable assets for the citizens’ wellbeing. Agglomerated and unintentional developments inevitably change the wind patterns which potentially affect public life. A longitudinal study of such circumstance will provide knowledge and lessons for sustainable and salutary urban design. Based on CFD simulation, this paper compared the static winter and summer airflows patterns of the Drum Tower area in downtown Nanjing during the period of 1990s-2010s. The results indicated that the wind pattern complexity increased gradually, the outdoor comfortability degraded dramatically in some areas, the environment inequity might be deteriorated too. The researcher suggests putting micro-climate issues firmly on the agenda of public wellbeing policy, involving various stakeholders in the assessment and urban design code with technical and social supports.