Human Mobility Networks Manifest Dissimilar Resilience Characteristics at Macroscopic, Substructure, and Microscopic Scales

Abstract

Human mobility networks can reveal insights into resilience phenomena, such as population response to, impacts on, and recovery from crises. The majority of human mobility network resilience characterizations, however, focus mainly on macroscopic network properties; little is known about variation in measured resilience characteristics (i.e., the extent of impact and recovery duration) across macroscopic, substructure (motif), and microscopic mobility scales. To address this gap, in this study, we examine the human mobility network in eight parishes in Louisiana (USA) impacted by the 2021 Hurricane Ida. We constructed human mobility networks using location-based data and examined three sets of measures: (1) macroscopic measures, such as network density, giant component size, and modularity; (2) substructure measures, such motif distribution; and (3) microscopic mobility measures, such as the radius of gyration and average travel distance. To determine the extent of impact and duration of recovery, for each measure, we established the baseline values and examined the fluctuation of measures during the perturbation caused by Hurricane Ida. The results reveal the variation of impact extent and recovery duration obtained from different sets of measures at different scales. Macroscopic measures, such as giant components, tend to recover more quickly than substructure and microscopic measures. In fact, microscopic measures tend to recover more slowly than measures in other scales. These findings suggest that resilience characteristics in human mobility networks are scale-variant, and thus, a single measure at a particular scale may not be representative of the perturbation impacts and recovery duration in the network as a whole. These results spotlight the need to use measures at different scales to properly characterize resilience in human mobility networks.

Spillover Effects of Built-Environment Vulnerability on Resilience of Businesses in Urban Crises

“…The objective of this study is to uncover the ripple effects of residential building flood damage on business recovery using fine-grained observational datasets (Figure 1). Our study leverages the strength of detailed mobility [44] [41] [15] and property damage data, offering new insights into the interplay of business recovery and property damage in the aftermath of a disaster and the effect of socio-economic factors that influence this process. We use a high-resolution location-mobility dataset along with property-level flood damage data in the context of the 2017 Hurricane Harvey in Harris County (Texas) to examine: (1) the association between damage extent and business recovery speed; (2) the sensitivity of different business types to residential flood damage in nearby neighborhoods; and (3) the variation in the extent of the sensitivity of business recovery to residential flood damage across areas with different income levels.…”