A Proposal to Integrate System Dynamics and Carbon Metabolism for Urban Planning

Coupling of life-cycle thinking with urban metabolism (UM) has the potential to improve sustainable urban planning. Current urban metabolism models are largely 'black-box' methods which do not reveal the non-linearity of feedback loops and complex internal dynamics of urban systems. The integration of system dynamics (SD) with UM based on a life-cycle thinking approach can provide built environment professionals (e.g. town planners, civil engineers, architects) with a 'transparent-box' solution for assessing the potential of urban projects, plans, and their implementation. This paper describes the development of a method that integrates input-output (IO) table flows with SD modelling to improve the completeness of UM assessments. This modelling framework can also allow for a 'nested' multi-region assessment which takes into account sustainability burdens consequent to urban system changes occurring elsewhere in the national and/or global economy. Pros and cons of this proposal are showcased by the illustration of a model for Lisbon.