Measuring the Impact of Transportation Diversity on Disaster Resilience in Urban Communities: Case Study of Hurricane Harvey in Houston, TX

摘要

The transportation system in urban areas plays a critical role in evacuation and resource supply during disasters. Transportation diversity, i.e., the availability and distribution of transportation modes across a community, impacts the mode complementarity, which can affect population movements and connectivity among spatial units—especially during extreme events when a failure in one mode can be compensated by other modes. However, few quantitative efforts have explored the impact of physical infrastructure configurations, and more specifically transportation diversity, on urban mobility and connectivity in an actual disaster context. In this paper, we measure transportation diversity with two factors—functional richness and functional evenness translated from the concept of diversity in ecological systems. Disaster resilience is regarded as a dynamic process pre, during, and post disaster in distinct communities and is tracked and quantified based on geospatial Twitter data of population cross-ZIP code tabulation areas movements with an ecology-inspired method—Fisher information—over time. Specifically, we compared the resilience of different neighborhoods in the city of Houston in Hurricane Harvey and found that neighborhoods with a higher level of transportation diversity demonstrated higher resiliency in their mobility during and after the hurricane. This study contributes to understanding how the availability and distribution of transportation infrastructure can impact the disaster resilience of human-infrastructure systems in urban areas. The results can improve transportation design and future urban planning, especially in the context of climate change and natural hazards.