As urbanization surges and climate change intensifies, cities worldwide are facing an increasing number of coupled risks. A recent paper published in Engineering offers fresh insights into understanding and managing these risks.

The complexity of coupled risks in cities, which result from the compounded effects of interacting uncertainties across multiple interdependent objectives, is a major concern. A disruption in one urban subsystem can trigger a chain reaction, affecting other subsystems and leading to unforeseen consequences. For example, the extreme rainfall not only damaged infrastructure but also disrupted socioeconomic activities, governance, and the environment.

Current risk assessment models often fall short in capturing the complexity of these processes, especially when it comes to factoring in human decision-making. To address this, the researchers propose four core perspectives.

First, they advocate for a standardized taxonomy of cascading hazards, urban components, and their interactions. This taxonomy should be people-centric, highlighting the bidirectional interactions between people and urban systems. It will help in better understanding how risks propagate and will be crucial for improving risk assessments and developing early warning systems.

Second, an integrated, people-centric risk assessment framework is needed. This framework should consider infrastructural, economic, social, environmental, and governmental dimensions, as well as individual behaviors and decision-making processes. Agent-based models can be used, but they need to be based on a uniform taxonomy and account for the hierarchical needs of people during crises.

Third, models should be calibrated using multi-source data. Although various data sources exist, each has limitations. By integrating data from different sources, such as social media, satellite imagery, and official reports, and using data-mining techniques, more accurate and reliable models can be developed. These models also need to be continuously updated to adapt to the dynamic nature of cities.

Finally, the researchers emphasize the importance of prioritizing people-centric strategies. These strategies can be divided into two categories: those related to what individuals can offer, like promoting individual engagement in risk reduction, and those related to what individuals can receive, such as providing timely warnings and education.

The research also points out that to turn these perspectives into practical solutions, more empirical case studies are required. Additionally, the integration of emerging technologies like artificial intelligence and digital twins can enhance the modeling and validation of risk assessment frameworks. A systematic roadmap is needed to integrate these ideas into practice, potentially giving rise to a new interdisciplinary field—“urban risk science.” This research paves the way for cities to become more resilient in the face of various risks, contributing to the United Nations’ Sustainable Development Goals.

The paper “Coupled Urban Risks: A Complex Systems Perspective with a People-Centric Focus,” authored by Min Ouyang, Zekai Cheng, Jiaxin Ma, Hongwei Wang, Stergios Aristoteles Mitoulis. Full text of the open access paper: https://doi.org/10.1016/j.eng.2024.12.023.