Post-hurricane accessibility to critical facilities is crucial for accelerating the recovery process, which can often be disrupted by hurricane-induced flooding. The State of Florida is especially vulnerable to flooding accompanied by hurricanes, which leads to significant roadway closures and accessibility challenges that require special attention. As such, this research aims to analyze changes in accessibility to critical facilities due to Hurricane Irma-induced flooding. Accordingly, this research aims to compare the average accessibility changes to critical facilities for vulnerable populations, including older people, disabled people, and older people with a disability with the general population. To accomplish these goals, flood mapping was done by analyzing Sentinel-1 images before and after Hurricane Irma (2017) using Google Earth Engine. The accessibility change from block groups to critical facilities was analyzed using a cumulative opportunities approach in GIS, considering flooded areas as the barriers, which were later aggregated to the county level. Finally, employing the population-weighted average accessibility method, a comparison of accessibility change of vulnerable and general populations was conducted. The result shows that 1193.80 square km of areas in 43 counties of Florida, mostly in the southern portions, were affected by flooding after Hurricane Irma. Later, the accessibility changes to critical facilities considering 15-min and 30-min travel time thresholds are presented and visualized. The county-wise change in accessibility of vulnerable and general populations was also computed. The knowledge acquired from this research can improve the development of efficient and equitable post-disaster recovery plans.

中文翻译：

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飓风洪水和基础设施破坏对关键设施可达性影响的大规模建模

飓风过后关键设施的通行对于加速恢复过程至关重要，而恢复过程往往会因飓风引发的洪水而中断。佛罗里达州特别容易受到飓风带来的洪水的影响，这会导致严重的道路封闭和通行挑战，需要特别关注。因此，本研究旨在分析飓风艾尔玛引发的洪水导致关键设施可达性的变化。因此，本研究旨在将弱势群体（包括老年人、残疾人和残疾老年人）的关键设施的平均可达性变化与普通人群进行比较。为了实现这些目标，我们使用 Google Earth Engine 分析飓风艾尔玛（2017 年）前后的 Sentinel-1 图像来完成洪水测绘。使用 GIS 中的累积机会方法分析从街区组到关键设施的可达性变化，将洪水区域视为障碍，然后将其汇总到县一级。最后，采用人口加权平均可达性方法，对弱势群体与一般人群的可达性变化进行了比较。结果显示，飓风艾尔玛后，佛罗里达州43个县的1193.80平方公里地区受到洪水影响，其中大部分位于南部地区。随后，考虑了 15 分钟和 30 分钟出行时间阈值，关键设施的可达性变化被呈现并可视化。还计算了弱势群体和一般人群的可及性在县范围内的变化。从这项研究中获得的知识可以改进有效和公平的灾后恢复计划的制定。