Resilience of Urban Mobility Systems: Combining Urban Subsystems and Threats with a System Dynamics Approach

Urban systems are dynamic, complex, and often involve multiple stakeholders, resulting in responses with distinct time lags. A resilient urban mobility system should be able to neutralize the effects of disruptive events (threats) while maintaining its essential state of functionality. Given the lack of studies addressing threats to urban mobility and the concurrent impacts on the urban mobility system, a holistic analysis considering key elements of transport systems and their interactions is necessary. Thus, this study aims to describe and analyze the dynamics involved in a resilient urban mobility system using qualitative system dynamics modeling. We start by identifying the main system components, threats, interrelations, and interconnections. Then, we create causal loop diagrams (CLD) of the urban mobility system under different conditions: (i) in the essential state of functionality, (ii) affected by a disruptive event and (iii) still functioning due to its resilience. Analyzing the CLDs indicated that the dynamics involved in a resilient urban mobility system have a preventive nature as it reflects the importance of transport policies considering climate change and disaster prevention policies/measures. In addition, the results showed that public opinion and incentives to use sustainable transport play an important role in balancing the system. Therefore, the negative effects of threats on the system, such as deaths, damage to transport infrastructures, and collapse of mobility performance, can be prevented. The outcomes of this study may be used to support the process of planning and building resilient cities.