A flexible multi-scale system dynamics modelling framework to assess the socio-economic impact of urban Green Infrastructure

The uncertainty of climate change, the fast -growing increase of global (urban) population and, as a result, an intensified competition among urban land uses demand a transition towards spatial planning models that maximise resilience, sustainability, and land-efficiency of cities. To succeed on this transition, more rigorous, holistic, and flexible assessment approaches of Green Infrastructure (GI) are needed: i) to define better their economic costs, benefits (i.e. ecosystem services), and losses (i.e. ecosystem disservices); ii) to facilitate comparability between options (including grey alternatives); iii) to adapt their valuation to different context, socio-economic scenarios, and implementation models; iv) and to easily inform stakeholders and decision makers. To this end, we introduce a flexible multi-scale system dynamics modelling framework that can assess the socio - economic impact of urban GI (its ecosystem services and disservices) in a monetary and well-being value scale. For the monetary value scale, data from life cycle inventories, input -output models, and other process-based parameters of the system dynamics modules are translated to impact scores. This is done by calculating the marginal product of ecosystem services in both an economic production and a welfare function as an estimation of the s hadow prices of each service. The practicality of this framework to support urban planning decisions will be outlined through a methodological advancement’s roadmap, framed in the context of a current international project on re-naturing cities (Nature4Cities). Additionally, examples of previous cities and neighbourhood proposals will be used to show how our modelling approach could better inform future urban planning works.