Policy makers and scientists are increasingly concerned with how extreme heat events impact cities and their populations. In a new study that came out published this week, we propose the new Transit Heat Exposure Index (THEI) to gauge high-fidelity heat exposure for transit riders. We demonstrate the proposed method using using 1 m-by-1 m microclimate simulations and door-to-door transport network analysis in a case study of Miami, one of the hottest US cities.

We believe this could be a valuable tool to enhance transit resilience to heat and develop effective mitigation strategies across cities. I hope some of you’ll find it useful! The paper was written with amazing co-authors Xiaojiang Li, Xiang ‘Jacob’ Yan and led by the brilliant Luyu Liu

• Liu, L., Li, X., Pereira, R. H., & Yan, X. (2025). Measuring exposure to extreme heat in public transit systems. Journal of Transport Geography, 128, 104383.