Extreme heat disrupts daily life, economic activity, and public health, often resulting in severe illness or death. While these issues are a prominent and serious local challenge in Arizona, the solutions developed here can be adapted globally, aligning closely with Arizona State University’s charter to advance research that serves both local and global communities. Even if survivable, extreme heat can result in unlivable places (i.e., for work, play, or reproduction). Moreover, heat is experienced by all, yet some more than others (e.g., certain occupations, children, and minority and low-income groups). To address health hazards posed by extreme heat, one must understand the complexities of human-environment heat exchange and resulting impacts on the human body in real-world built environments.
However, we currently have limited understanding of how the time-course of extreme heat exposure in outdoor or indoor locations advances from thermal discomfort to heat stress, strain, illness, and death. This information cannot be directly measured because prolonged human exposure to extreme heat is dangerous; hence, realistic, validated simulations and models across the full cascade of impacts are missing. In project funded by $2 million NSF Leading Engineering for America’s Prosperity, Health, and Infrastructure (LEAP-HI) program we are leveraging expertise from disparate disciplines to pioneer three novel field method to allow a realistic heat exposure and thermoregulatory response assessment across various demographics, body shapes, and scenarios (from Olympic runners to the unsheltered population). Specifically, we are developing 1) CARla+: merging our cost-effective and highly portable cylindrical sensors with improved Stolwijk thermoregulation model, 2) MaRTy3D+: merging Prof. Ariane Middel’s advanced biometeorological cart with the improved Stolwijk thermoregulation model, and 3) “adaptive mode” thermal manikin ANDI coupled with ThermoAnalytics Taitherm thermoregulation model. These tools provide new ways to evaluate how behaviors, clothing, policy interventions, and infrastructure can impact heat stress, while protecting human health.
Representative publications:
Joshi, A.,* Twidwell, B., Park, M., and Rykaczewski, K.,* Comparative Analysis of Thermoregulation Models to Assess Heat Strain in Moderate to Extreme Heat, Journal of Thermal Biology, (2025).
Vanos, J.K.,* Joshi, A., Guzman-Echavarria, G., Rykaczewski, K., and Hosokawa, Y. Impact of Reflective Roadways on Heat Strain at the Tokyo, Paris, and Los Angeles Olympics, Journal of Science in Sport and Exercise, (2024).
Karanja, J.*, Vanos, J.K., Joshi, A., Penner, S., Guzman-Echavaria, G., Connor, D.S., Rykaczewski, K., Impact of Tent Shade on Heat Exposures and Simulated Heat Strain for People Experiencing Homelessness, International Journal of Biometeorology, (2024).
