An integrated, multi-scale approach for modelling urban metabolism changes as a means for assessing urban sustainability

Advancing urban sustainability requires implementing various measures in multiple fields including public policy and planning, behavioral change, technological development, within and beyond a city's boundaries. Local and national governments, as well as citizens and organizations, need a way to understand and evaluate the potential implications, positive or negative, of selected measures aimed to improve urban sustainability. "Urban metabolism" quantifies the amounts of materials and energy that flow through a city. It can provide important information about overall urban-natural system interactions. To date, several studies have analyzed the metabolism of cities in different parts of the world. As an indicator of urban sustainability, this is a powerful tool that can be the base for a road map for advancing changes in the way a studied city operates. Analyzing the material and energy metabolism of specific sectors and activities within the city makes it possible to identify major loads and potential points of intervention for reducing urban impacts. Previous research (Kissinger & Stossel, 2019) introduced a multi-scale spatial approach to analyzing urban metabolism, which was illustrated on the city of Tel Aviv-Jaffa, Israel. The study presented below models the options of changing the city's metabolism and reducing its environmental impact on the local, regional and global scales by implementing various measures. It also illustrates the different potential outcomes of policies when they are examined as a single, isolated measure, or as part of the interaction between several measures. First, we analyze the implications of existing urban and national policy measures for the urban metabolism on various spatial scales. Then, we test those measures while considering projected population growth and changes of consumption patterns. Finally, we analyze an alternative, more progressive scenario set that integrates advanced measures that could significantly reduce the urban metabolism and improve the urban sustainability.