Walking infrastructure is important for livable and sustainable cities, especially for vulnerable populations. However, extreme temperatures can increase walk time and potentially cause health concerns. Due to their sensitivity to extreme temperatures, more frequent use of the sidewalk network, and reduced trip elasticity, senior citizens are particularly vulnerable to extreme temperatures. The project will extend Georgia Tech’s previous effort in designing its family of mode and path-specific multi-modal transportation simulator elements, in parallel support of the Atlanta Regional Commission’s ITS4US project.
This research will first model apparent temperature (also known as heat index, or perceived equivalence temperature) using open source data and widely validated models. Then, the mapped temperature will be used to update impedance cost functions for pedestrian activity for both walking time and health risk. The impedance functions in the SidewalkSim model will be updated to include user-group-specific tradeoff factors between the two types of costs. A user route choice predictor function will be included in preparation for future deployment as a navigation app. A case study application will be performed for senior citizen pedestrians that reside in Gwinnett County, GA, to investigate the relationship between age, weather condition, and travel behavior. The results of this study will help planners understand how changes in extreme weather conditions over time may adversely affect vulnerable user communities.