Thermal Comfort
Exploring the impact of heat and cold exposure on transit and pedestrian trips, with a focus on equity, health, and climate resilience.
Background
Extreme temperatures — both heat and cold — pose serious threats to travelers in urban environments, particularly for vulnerable populations such as the elderly, people with chronic conditions, or those with limited mobility. While existing studies provide segment-level exposure analysis or qualitative accounts, there's a lack of high-resolution, trip-level modeling to quantify thermal exposure and predict health outcomes.
Framework Overview
Trip-Level Exposure Modeling
We model real-time exposure using physical activity, physiological responses, and weather overlays during transit, walking, and waiting phases of a trip.
Behavioral Response
Our models predict how discomfort and health risk influence travelers' route or mode choice, and estimate downstream effects on access and equity.
Disparities and Mitigation
We analyze thermal inequities across populations and evaluate the effectiveness of greening strategies and shelters in lowering physiological strain.
Ongoing Work
Our current efforts focus on modeling the dose-response relationships between thermal exposure and health outcomes, with special attention to vulnerable populations such as the elderly, people with disabilities, and those with chronic conditions. Our team is also investigating the restorative effects of various mitigation strategies—such as shade, cooling hubs, and heated shelters—to understand how they reduce risk during travel. These insights guide our collaborations with planners and public health experts to inform climate-adaptive infrastructure design that prioritizes health and equity.
Join Us
If you're a prospective student interested in pursuing research related to this topic, please visit this page for the latest updates on graduate opportunities. When completing your application, be sure to type "[Thermal Comfort]" in response to the question: "If there are any special circumstances that you'd like me to know about, please list them here." (If there are actual circumstances to share, feel free to elaborate after the square brackets).
Related Publications
- Fan, H., Lu, H., Lyu, G., Guin, A., & Guensler, R. (2024). A framework for assessing cumulative exposure to extreme temperatures during transit trip. arXiv preprint, arXiv:2408.04081.
- Fan, H., Lyu, G., Lu, H., Guin, A., & Guensler, R. (2025). Transit rider heat stress and health: potential impacts of current and future extreme heat exposure in Atlanta, GA. Environmental Research Letters, 20(5), 054055. https://doi.org/10.1016/j.agrformet.2018.11.027.
- Fan, H., Yu, Z., Yang, G., Liu, T. Y., Liu, T. Y., Hung, C. H., & Vejre, H. (2019). How to cool hot-humid (Asian) cities with urban trees? An optimal landscape size perspective. Agricultural and Forest Meteorology, 265, 338–348. https://doi.org/10.1088/1748-9326/adc943.
- Doran, E., Reichard, W., Boothe, M., Donnell, G., Fan, H., Rowangould, G., & Guensler, R. (2025). Mitigating extreme heat exposure using advanced and novel materials and improved pedestrian infrastructure design: A systematic literature review and survey of agencies. https://doi.org/10.7922/G23J3BBH.
- Fan, H. (2024). Network-level modeling of transit riders and pedestrians’ thermal comfort. Georgia Institute of Technology, Theses and Dissertations. https://hdl.handle.net/1853/76890.
- Fan, H. (2025, January 30). Using high-performance computing to understand extreme weather impacts on vulnerable transit riders [Webinar]. National Center for Sustainable Transportation (NCST). https://ncst.ucdavis.edu/events/using-high-performance-computing-understand-extreme-weather-impacts-vulnerable-transit.