Significant negative impacts are observed in productivity, economy, and social wellbeing because of the reduced human activity due to extreme events. Community resilience is an important and widely used concept to understand the impacts of an extreme event to population activity. Resilience is generally defined as the ability of a system to manage shocks and return to a steady state in response to an extreme event. In this study, aggregate location data from Facebook in response to Hurricane Ida are analyzed. Using changes in the number of Facebook users before, during, and after the disaster, community resilience is quantified as a function of the magnitude of impact and the time to recover from the extreme situation. Based on the resilience function, the transient loss of resilience in population activity is measured for the affected communities in Louisiana. The loss in resilience of the affected communities are explained by three types of factors, including disruption in physical infrastructures, disaster conditions due to hurricanes, and socio-economic characteristics. A greater loss in community resilience is associated with factors such as disruptions in power and transportation services and disaster conditions. Socioeconomic disparities in loss of resilience are found with respect to median income of a community. Understanding community resilience using decreased population activity levels due to a disaster and the factors associated with losses in resilience will enable us improve hazard preparedness, enhance disaster management practices, and create better recovery policies towards strengthening infrastructure and community resilience.

翻译：极端事件导致的人类活动减少对生产力、经济和社会福祉产生了显著的负面影响。社区韧性是理解极端事件对人口活动影响的重要且广泛使用的概念。韧性通常被定义为系统在面对极端事件时管理冲击并恢复到稳定状态的能力。本研究分析了Facebook在应对"艾达"飓风时提供的聚合位置数据。通过考察灾难前后Facebook用户数量的变化，社区韧性被量化为冲击强度与从极端状态中恢复所需时间的函数。基于韧性函数，测量了路易斯安那州受影响社区人口活动的瞬时韧性损失。影响社区韧性损失的因素被归纳为三类：物理基础设施破坏、飓风灾害条件以及社会经济特征。电力与交通服务中断等基础设施破坏及灾害条件与更高的社区韧性损失显著相关。研究还发现，社区韧性损失存在基于社区收入中位数的社会经济差异。通过理解由灾害导致的人口活动下降所反映的社区韧性及其损失因素，我们能够改进灾害防备措施、优化灾害管理实践，并制定更完善的恢复政策，从而加强基础设施和社区韧性。